HP Pavilion a6600 User manual

HP A6600 Routers
Layer 2 - LAN Switching
Configuration Guide
Abstract
This document describes the software features for the HP A Series products and guides you through the
software configuration procedures. These configuration guides also provide configuration examples to
help you apply software features to different network scenarios.
This documentation is intended for network planners, field technical support and servicing engineers, and
network administrators working with the HP A Series products.
Part number: 5998-1501
Software version: A6600-CMW520-R2603
Document version: 6PW101-20110630

Legal and notice information
© Copyright 2011 Hewlett-Packard Development Company, L.P.
No part of this documentation may be reproduced or transmitted in any form or by any means without
prior written consent of Hewlett-Packard Development Company, L.P.
The information contained herein is subject to change without notice.
HEWLETT-PACKARD COMPANY MAKES NO WARRANTY OF ANY KIND WITH REGARD TO THIS
MATERIAL, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY
AND FITNESS FOR A PARTICULAR PURPOSE. Hewlett-Packard shall not be liable for errors contained
herein or for incidental or consequential damages in connection with the furnishing, performance, or use
of this material.
The only warranties for HP products and services are set forth in the express warranty statements
accompanying such products and services. Nothing herein should be construed as constituting an
additional warranty. HP shall not be liable for technical or editorial errors or omissions contained herein.

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Contents
MAC address table configuration ······························································································································ 1
How a MAC address table entry is created··········································································································1
Types of MAC address table entries ······················································································································2
MAC address table-based frame forwarding ·······································································································2
Configuring the MAC address table·······························································································································2
Configuring static, dynamic, and blackhole MAC address table entries ··························································2
Disabling MAC address learning···························································································································3
Configuring the aging timer for dynamic MAC address entries·········································································4
Configuring the MAC learning limit on ports········································································································5
Displaying and maintaining MAC address tables ········································································································5
MAC address table configuration example ···················································································································6
MAC information configuration·································································································································· 8
How MAC information works ·································································································································8
Configuring MAC information·········································································································································8
Enabling MAC information globally ······················································································································8
Enabling MAC information on an interface ··········································································································8
Configuring MAC information mode ·····················································································································9
Configuring the interval for sending Syslog or trap messages············································································9
Configuring the MAC information queue length ··································································································9
MAC information configuration example·······················································································································9
Ethernet link aggregation configuration···················································································································11
Basic concepts ······················································································································································· 11
Aggregating links in static mode························································································································· 14
Aggregating links in dynamic mode ··················································································································· 15
Load sharing criteria for link aggregation groups····························································································· 17
Ethernet link aggregation configuration task list········································································································· 17
Configuring an aggregation group ····························································································································· 17
Configuration guidelines ······································································································································ 17
Configuring a static aggregation group············································································································· 18
Configuring a dynamic aggregation group······································································································· 19
Configuring an aggregate interface ···························································································································· 21
Configuring the description of an aggregate interface or subinterface·························································· 21
Configuring the MTU of a Layer 3 aggregate interface or subinterface························································· 22
Specifying a card to process or forward traffic for a Layer 3 aggregate interface······································· 22
Enabling link state traps for an aggregate interface························································································· 23
Shutting down an aggregate interface ··············································································································· 23
Configuring load sharing for link aggregation groups······························································································ 24
Configuring the global link-aggregation load sharing criteria········································································· 24
Configuring group-specific load sharing criteria ······························································································· 25
Displaying and maintaining Ethernet link aggregation ····························································································· 25
Ethernet link aggregation configuration examples····································································································· 26
Layer 2 static aggregation configuration example···························································································· 26
Layer 2 dynamic aggregation configuration example······················································································ 28
Layer 2 aggregation load sharing configuration example··············································································· 30
Layer 3 static aggregation configuration example···························································································· 33
Layer 3 dynamic aggregation configuration example······················································································ 34
Layer 3 aggregation load sharing configuration example··············································································· 36

iv
Port isolation configuration········································································································································39
Configuring an isolation group ···································································································································· 39
Assigning a port to the isolation group ·············································································································· 39
Displaying and maintaining isolation groups ············································································································· 39
Port isolation configuration example ··························································································································· 40
MSTP configuration····················································································································································41
Why STP································································································································································· 41
Protocol packets of STP········································································································································· 41
Basic concepts in STP············································································································································ 41
How STP works······················································································································································ 43
RSTP················································································································································································· 48
MSTP ··············································································································································································· 49
Why MSTP ····························································································································································· 49
Basic concepts in MSTP········································································································································ 50
How MSTP works ·················································································································································· 53
Implementation of MSTP on devices···················································································································· 54
Protocols and standards ······································································································································· 54
MSTP configuration task list ·········································································································································· 54
Configuring MSTP·························································································································································· 56
Configuring an MST region ································································································································· 56
Configuring the root bridge or a secondary root bridge·················································································· 57
Configuring the work mode of an MSTP device································································································ 58
Configuring the priority of a device···················································································································· 58
Configuring the maximum hops of an MST region ··························································································· 59
Configuring the network diameter of a switched network················································································ 59
Configuring timers of MSTP ································································································································· 60
Configuring the timeout factor ····························································································································· 61
Configuring the maximum port rate ···················································································································· 61
Configuring ports as edge ports·························································································································· 62
Configuring path costs of ports···························································································································· 62
Configuring port priority······································································································································· 65
Configuring the link type of ports ························································································································ 65
Configuring the mode a port uses to recognize/send MSTP packets ····························································· 66
Enabling the output of port state transition information ···················································································· 67
Enabling the MSTP feature ··································································································································· 67
Performing mCheck··············································································································································· 68
Configuring digest snooping································································································································ 69
Configuring no agreement check ························································································································ 70
Configuring protection functions·························································································································· 72
MSTP configuration example········································································································································ 76
BPDU tunneling configuration ···································································································································81
BPDU tunneling implementation··························································································································· 82
Configuring BPDU tunneling ········································································································································· 83
Configuration prerequisites ·································································································································· 83
Enabling BPDU tunneling······································································································································ 83
Configuring destination multicast MAC address for BPDUs············································································· 84
BPDU tunneling configuration examples······················································································································ 85
BPDU tunneling for STP configuration example ································································································· 85
BPDU tunneling for PVST configuration example······························································································· 86
VLAN configuration ···················································································································································88
VLAN fundamentals ·············································································································································· 88
VLAN types ···························································································································································· 89
Configuring basic VLAN settings ································································································································· 90

v
Configuring basic settings of a VLAN interface ········································································································· 90
Port-based VLAN configuration ···································································································································· 91
Assigning an access port to a VLAN ·················································································································· 93
Assigning a trunk port to a VLAN ······················································································································· 94
Assigning a hybrid port to a VLAN····················································································································· 95
Port-based VLAN configuration example············································································································ 96
MAC-based VLAN configuration·································································································································· 98
Configuring a MAC-based VLAN························································································································ 99
MAC-based VLAN configuration example ·······································································································100
Protocol-based VLAN configuration···························································································································102
Introduction to protocol-based VLAN ················································································································102
Configuring a protocol-based VLAN·················································································································103
Protocol-based VLAN configuration example ··································································································104
IP subnet-based VLAN configuration··························································································································107
Configuring an IP subnet-based VLAN ·············································································································107
Displaying and maintaining VLAN ····························································································································108
Super VLAN configuration ····································································································································· 109
Configuring a super VLAN ·········································································································································109
Displaying and maintaining super VLAN··················································································································111
Super VLAN configuration example ··························································································································111
Isolate-user-VLAN configuration ····························································································································· 114
Configuring an isolate-user-VLAN ······························································································································114
Displaying and maintaining isolate-user-VLAN·········································································································115
Isolate-user-VLAN configuration example··················································································································116
Voice VLAN configuration······································································································································ 119
OUI addresses ·····················································································································································119
Voice VLAN assignment modes·························································································································120
Security mode and normal mode of voice VLANs···························································································122
Configuring a voice VLAN··········································································································································123
Configuration prerequisites ································································································································123
Configuring QoS priority settings for voice traffic on an interface································································123
Configuring a port to operate in automatic voice VLAN assignment mode·················································124
Configuring a port to operate in manual voice VLAN assignment mode·····················································125
Displaying and maintaining voice VLAN ··················································································································126
Voice VLAN configuration examples·························································································································126
Automatic voice VLAN mode configuration example ·····················································································126
Manual voice VLAN assignment mode configuration example ·····································································128
GVRP configuration················································································································································· 131
GARP ····································································································································································131
GVRP ····································································································································································134
Protocols and standards ·····································································································································134
GVRP configuration task list········································································································································135
Configuring GVRP functions ·······································································································································135
Configuring the garp timers········································································································································136
Displaying and maintaining GVRP·····························································································································137
GVRP configuration examples····································································································································138
GVRP normal registration mode configuration example·················································································138
GVRP fixed registration mode configuration example ····················································································139
GVRP forbidden registration mode configuration example············································································140
QinQ configuration ················································································································································ 143
Background and benefits····································································································································143
How QinQ works················································································································································143

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QinQ frame structure ··········································································································································144
Implementations of QinQ ···································································································································145
Modifying the TPID in a VLAN tag····················································································································145
Protocols and standards ·····································································································································146
QinQ configuration task list········································································································································146
Configuring basic QinQ ·············································································································································147
Enabling basic QinQ··········································································································································147
Configuring VLAN transparent transmission ····································································································147
Configuring selective QinQ········································································································································148
Configuring an outer VLAN tagging policy ·····································································································148
Configuring an inner-outer VLAN 802.1p priority mapping··········································································149
Configuring inner VLAN ID substitution ············································································································150
Configuring the TPID value in VLAN tags ·················································································································151
QinQ configuration examples····································································································································152
Basic QinQ configuration example···················································································································152
Selective QinQ configuration example·············································································································154
VLAN transparent transmission configuration example ··················································································157
VLAN termination configuration ···························································································································· 160
VLAN termination types······································································································································160
Application scenarios ·········································································································································160
VLAN termination configuration task list ···················································································································162
Configuring TPID for VLAN-tagged packets··············································································································162
Introduction to TPID ·············································································································································162
Configuring TPID on Layer 3 Ethernet/aggregate subinterfaces ···································································163
Enabling an ambiguous Dot1q/QinQ termination-enabled subinterface to transmit broadcasts and
multicasts·······································································································································································164
Configuring Dot1q termination···································································································································165
Configuring unambiguous Dot1q termination··································································································165
Unambiguous Dot1q termination configuration example ···············································································165
Configuring ambiguous Dot1q termination······································································································167
Ambiguous Dot1q termination configuration examples··················································································168
Configuration examples for Dot1q termination supporting PPPoE server ·····················································169
Configuring QinQ termination ···································································································································170
Configuring unambiguous QinQ termination ··································································································170
Unambiguous QinQ termination configuration example················································································170
Configuring ambiguous QinQ termination ······································································································172
Ambiguous QinQ termination configuration example····················································································173
Configuration example for QinQ termination supporting PPPoE server ·······················································174
Configuration example for QinQ termination supporting DHCP relay ·························································174
VLAN mapping configuration ································································································································ 178
Application scenario of one-to-one VLAN mapping························································································179
Application scenario of one-to-two and two-to-two VLAN mapping······························································180
Concepts and terms ············································································································································181
VLAN mapping implementations·······················································································································182
Configuring VLAN mapping ·······································································································································183
Configuring one-to-one VLAN mapping ···········································································································183
Configuring one-to-two VLAN mapping············································································································186
Configuring two-to-two VLAN mapping············································································································187
VLAN mapping configuration examples ···················································································································191
One-to-one VLAN mapping configuration example ························································································191
One-to-two and two-to-two VLAN mapping configuration example ······························································195
LLDP configuration··················································································································································· 199
Basic concepts ·····················································································································································199

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How LLDP works ··················································································································································203
Protocols and standards ·····································································································································204
LLDP configuration task list ··········································································································································204
Performing basic LLDP configuration··························································································································204
Enabling LLDP ······················································································································································204
Setting the LLDP operating mode ·······················································································································205
Setting the LLDP re-initialization delay ··············································································································205
Enabling LLDP polling ·········································································································································206
Configuring the advertisable TLVs ·····················································································································206
Configuring the management address and its encoding format····································································207
Setting other LLDP parameters····························································································································208
Setting an encapsulation format for LLDPDUs ··································································································208
Configuring CDP compatibility···································································································································209
Configuration prerequisites ································································································································209
Configuration procedure ····································································································································209
Configuring LLDP trapping ··········································································································································210
Displaying and maintaining LLDP·······························································································································210
LLDP configuration examples ······································································································································211
Basic LLDP configuration example·····················································································································211
CDP-compatible LLDP configuration example···································································································214
Support and other resources ·································································································································· 216
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1
MAC address table configuration
The MAC address table configuration applies only to Layer 2 interfaces, including Layer 2 Ethernet
interfaces and Layer 2 aggregate interfaces.
This document covers only the configuration of unicast MAC address table entries, including static,
dynamic, and blackhole MAC address table entries. For more information about configuring static
multicast MAC address table entries, see IP Multicast Configuration Guide.
The SAP cards support the MAC address table configuration only when they work in Layer 2 mode.
An Ethernet router uses a MAC address table for forwarding frames through unicast instead of broadcast.
This table describes from which port a MAC address (or host) can be reached. When forwarding a frame,
the router first looks up the MAC address of the frame in the MAC address table for a match. If an entry is
found, the router forwards the frame out of the outgoing port in the entry. If no entry is found, the router
broadcasts the frame out of all but the incoming port.
How a MAC address table entry is created
The entries in the MAC address table come from two sources: automatically learned by the router and
manually added by the administrator.
MAC address learning
The router can populate its MAC address table automatically by learning the source MAC addresses of
incoming frames on each port.
When a frame arrives at a port, Port A for example, the router performs the following tasks:
1. Checks the source MAC address (for example, MAC-SOURCE) of the frame.
2. Looks up the MAC address in the MAC address table.
3. If an entry is found, updates the entry. If no entry is found, adds an entry for MAC-SOURCE and Port
A.
The router performs the learning process each time it receives a frame from an unknown source MAC
address, until the MAC address table is fully populated.
After learning the source MAC address of a frame, the router looks up the destination MAC address in
the MAC address table. If an entry is found for the MAC address, the router forwards the frame out of the
specific outgoing port. In this example, it is Port A.
Manually configuring MAC address entries
With dynamic MAC address learning, a router does not distinguish between illegitimate and legitimate
frames. This can invite security hazards. For example, when a hacker sends frames with a forged source
MAC address to a port different from the one to which the real MAC address is connected, the router
creates an entry for the forged MAC address, and forwards frames destined for the legal user to the
hacker instead.
To enhance the security of a port, manually add MAC address entries to the MAC address table of the
router to bind specific user devices to the port. Because manually configured entries have higher priority
than dynamically learned ones, you can prevent hackers from stealing data using forged MAC
addresses.

2
Types of MAC address table entries
A MAC address table can contain the following types of entries:
•Static entries, which are manually added and never age out.
•Dynamic entries, which can be manually added or dynamically learned and may age out.
•Blackhole entries, which are manually configured and never age out. Blackhole entries are
configured for filtering out frames with specific MAC addresses. For example, to block all packets
destined for a specific user for security concerns, configure the MAC address of this user as a
blackhole MAC address entry.
To adapt to network changes and prevent inactive entries from occupying table space, an aging
mechanism is adopted for dynamic MAC address entries. Each time a dynamic MAC address entry is
learned or created, an aging time starts. If the entry has not updated when the aging timer expires, the
router deletes the entry. If the entry has updated before the aging timer expires, the aging timer restarts.
A static or blackhole MAC address entry can overwrite a dynamic MAC address entry, but not vice
versa.
MAC address table-based frame forwarding
When forwarding a frame, the router adopts the following forwarding modes based on the MAC address
table:
•Unicast mode: If an entry is available for the destination MAC address, the router forwards the
frame out the outgoing interface indicated by the MAC address table entry.
•Broadcast mode: If the router receives a frame with the destination address being all ones, or no
entry is available for the destination MAC address, the router broadcasts the frame to all interfaces
except the receiving interface.
Configuring the MAC address table
These configuration tasks are all optional and can be performed in any order.
Configuring static, dynamic, and blackhole MAC address table
entries
To fence off MAC address spoofing attacks and improve port security, manually add MAC address table
entries to bind ports with MAC addresses.
Also, configure blackhole MAC address entries to filter out packets with certain MAC addresses.

3
Add or modify a static, dynamic, or blackhole MAC address table entry globally
To add or modify a static, dynamic, or blackhole MAC address table entry in system view:
To do… Use the command… Remarks
1. Enter system view system-view —
2. Add or modify a
dynamic or static MAC
address entry
mac-address { dynamic |static }mac-address
interface interface-type interface-number vlan
vlan-id
Required.
Use either command.
Ensure that you have
created the VLAN and
assign the interface to the
VLAN.
3. Add or modify a
blackhole MAC address
entry
mac-address blackhole mac-address vlan
vlan-id
Add or modify a static or dynamic MAC address table entry on an interface
To add or modify a static or dynamic MAC address table entry in interface view:
To do… Use the command… Remarks
1. Enter system view system-view —
2. Enter interface view interface interface-type
interface-number —
3. Add or modify a static or
dynamic MAC address entry
mac-address { dynamic | static }
mac-address vlan vlan-id
Required.
Ensure that you have created the
VLAN and assign the interface to
the VLAN.
Disabling MAC address learning
You may need to disable MAC address learning sometimes to prevent the MAC address table from being
saturated. For example, you may need to do it when your router is being attacked by a large amount of
packets with different source MAC addresses.
Disabling global MAC address learning
Disabling global MAC address learning disables the learning function on all ports.
To disable MAC address learning:
To do… Use the command… Remarks
1. Enter system view system-view —
2. Disable global MAC address
learning mac-address mac-learning disable Required
Enabled by default
Disabling MAC address learning on ports
After enabling global MAC address learning, you may disable the function on a single port, or on all
ports in a port group as needed.

4
To disable MAC address learning on an interface or a port group:
To do… Use the command… Remarks
1. Enter system view system-view —
2. Enable global MAC address
learning
undo mac-address
mac-learning disable
Optional.
Enabled by default.
3. Enter
interface
view or
port
group
view
Enter Layer 2
Ethernet/aggregate
interface view
interface interface-type
interface-number
Required.
Use either command.
Settings in Layer 2
Ethernet/aggregate interface view
take effect on the current interface
only.
Settings in port group view take
effect on all member ports in the
port group.
Enter port group view port-group manual
port-group-name
4. Disable MAC address learning on
the interface or all ports in the port
group
mac-address mac-learning
disable
Required.
By default, MAC address learning
is enabled on ports.
For configuration about port groups, see the chapter “Ethernet interface configuration.”
Disabling MAC address learning on a VLAN
You may disable MAC address learning on a per-VLAN basis.
To disable MAC address learning on a VLAN:
To do… Use the command… Remarks
1. Enter system view system-view —
2. Enable global MAC address
learning
undo mac-address mac-learning
disable
Optional
Enabled by default
3. Enter VLAN view vlan vlan-id —
4. Disable MAC address
learning on the VLAN mac-address mac-learning disable Required
Enabled by default
Configuring the aging timer for dynamic MAC address entries
The MAC address table uses an aging timer for dynamic MAC address entries for security and efficient
use of table space. If a dynamic MAC address entry has failed to update before the aging timer expires,
the router deletes the entry. This aging mechanism ensures that the MAC address table could timely
update to accommodate latest network changes.
Set the aging timer appropriately. A long aging interval may cause the MAC address table to retain
outdated entries, exhaust the MAC address table resources, and fail to update its entries to accommodate
the latest network changes. A short interval may result in the removal of valid entries and unnecessary
broadcasts, which may affect router performance.

5
To configure the aging timer for dynamic MAC address entries:
To do… Use the command… Remarks
1. Enter system view system-view —
2. Configure the aging timer for
dynamic MAC address entries
mac-address timer { aging
seconds | no-aging }
Optional
300 seconds by default
Reduce broadcasts on a stable network by disabling the aging timer to prevent dynamic entries from
aging out unnecessarily. By reducing broadcasts, you improve not only network performance, but also
security, because the chances for a data packet to reach unintended destinations are reduced.
Configuring the MAC learning limit on ports
As the MAC address table is growing, the forwarding performance of your router may degrade. To
prevent the MAC address table from getting so large that the forwarding performance is affected, limit
the number of MAC addresses that can be learned on a port.
To configure the MAC learning limit on a Layer 2 Ethernet interface, Layer 2 VE interface, Layer 2
aggregate interface, or all ports in a port group:
To do… Use the command… Remarks
1. Enter system view system-view —
2. Enter
interface
view or
port
group
view
Enter Layer 2
Ethernet/aggregate
interface view
interface interface-type
interface-number
Required.
Use either command.
Settings in Layer 2
Ethernet/aggregate interface
view take effect on the current
interface only.
Settings in port group view take
effect on all member ports in the
port group.
Enter port group view port-group manual
port-group-name
3. Configure the MAC learning limit
on the interface or port group, and
configure whether frames with
unknown source MAC addresses
can be forwarded or not when the
MAC learning limit is reached
mac-address max-mac-count
count
Required.
By default, the MAC learning
limit is not configured on ports.
Displaying and maintaining MAC address tables
To do… Use the command… Remarks
Display MAC address table
information
display mac-address [ mac-address [ vlan vlan-id ] |
[ [ dynamic | static ] [ interface interface-type
interface-number ] | blackhole ] [ vlan vlan-id ]
[ count ] ] [ |{ begin | exclude | include }
regular-expression ]
Available in any view

6
To do… Use the command… Remarks
Display the aging timer for
dynamic MAC address
entries
display mac-address aging-time [ |{ begin |
exclude | include } regular-expression ] Available in any view
Display the system or
interface MAC address
learning state
display mac-address mac-learning [ interface-type
interface-number ] [ |{ begin | exclude | include }
regular-expression ]
Available in any view
Display MAC address
statistics
display mac-address statistics [ |{ begin | exclude
| include } regular-expression ] Available in any view
MAC address table configuration example
Network requirements
As shown in Figure 1:
•The MAC address of Host A is 000f-e235-dc71 and belongs to VLAN 1. It is connected to
GigabitEthernet 4/0/1 of the router. To prevent MAC address spoofing, add a static entry into the
MAC address table of the router for the host.
•The MAC address of Host B is 000f-e235-abcd and belongs to VLAN 1. Because this host once
behaved suspiciously on the network, you can add a blackhole MAC address entry for the MAC
address to drop all packets destined for the host.
•Set the aging timer for dynamic MAC address entries to 500 seconds.
Figure 1 Network diagram for MAC address table configuration
Configuration procedure
# Add a static MAC address entry.
<Router> system-view
[Router] mac-address static 000f-e235-dc71 interface gigabitethernet 4/0/1 vlan 1
# Add a blackhole MAC address entry.
[Router] mac-address blackhole 000f-e235-abcd vlan 1
# Set the aging timer for dynamic MAC address entries to 500 seconds.
[Router] mac-address timer aging 500

7
# Display the MAC address entry for port GigabitEthernet 4/0/1.
[Router] display mac-address interface gigabitethernet 4/0/1
MAC ADDR VLAN ID STATE PORT INDEX AGING TIME(s)
000f-e235-dc71 1 Config static GigabitEthernet 4/0/1 NOAGED
--- 1 mac address(es) found ---
# Display information about the blackhole MAC address table.
[Router] display mac-address blackhole
MAC ADDR VLAN ID STATE PORT INDEX AGING TIME
000f-e235-abcd 1 Blackhole N/A NOAGED
--- 1 mac address(es) found ---
# View the aging time of dynamic MAC address entries.
[Router] display mac-address aging-time
Mac address aging time: 500s

8
MAC information configuration
The SAP cards support this feature only when they work in Layer 2 mode.
To monitor a network, you need to monitor users joining and leaving the network. Because a MAC
address uniquely identifies a network user, monitor those users joining and leaving a network by
monitoring their MAC addresses.
With the MAC information function, Layer 2 Ethernet interfaces send Syslog or trap messages to the
monitor end in the network when they learn or delete MAC addresses. By analyzing these messages, the
monitor end can monitor users accessing the network.
How MAC information works
When a new MAC address is learned or an existing MAC address is deleted on a router, the router
writes related information about the MAC address to the buffer area used to store user information.
When the timer set for sending MAC address monitoring Syslog or trap messages expires, or when the
buffer is used up, the router sends the Syslog or trap messages to the monitor end immediately.
Configuring MAC information
Enabling MAC information globally
To enable MAC information globally:
To do… Use the command… Remarks
1. Enter system view system-view —
2. Enable MAC information
globally mac-address information enable Required
Disabled by default
Enabling MAC information on an interface
To enable MAC information on an interface:
To do… Use the command… Remarks
1. Enter system view system-view —
2. Enter Layer 2 Ethernet
interface view
interface interface-type
interface-number —
3. Enable MAC information on
the interface
mac-address information enable
{added |deleted }
Required
Disabled by default
To enable MAC information on an Ethernet interface, enable MAC information globally first.

9
Configuring MAC information mode
To configure MAC information mode:
To do… Use the command… Remarks
1. Enter system view system-view —
2. Configure MAC information
mode
mac-address information mode
{ syslog | trap }
Optional
trap by default
Configuring the interval for sending Syslog or trap messages
To prevent Syslog or trap messages from being sent too frequently, set the interval for sending Syslog or
trap messages.
To set the interval for sending Syslog or trap messages:
To do… Use the command… Remarks
1. Enter system view system-view —
2. Set the interval for sending
Syslog or trap messages
mac-address information interval
interval-time
Optional
One second by default
Configuring the MAC information queue length
To avoid losing user MAC address information, when the buffer storing user MAC address information is
used up, the user MAC address information in the buffer is sent to the monitor end in the network, even if
the timer set for sending MAC address monitoring Syslog or trap messages has not expired yet.
To configure the MAC information queue length:
To do… Use the command… Remarks
1. Enter system view system-view —
2. Configure the MAC
information queue length
mac-address information
queue-length value
Optional
50 by default
MAC information configuration example
Network requirements
As shown in Figure 2:
•Host A is connected to a remote server (Server) through Router.
•Enable MAC information on GigabitEthernet 4/0/1 on Router. Router sends MAC address changes
in Syslog messages to Host B through GigabitEthernet 4/0/3. Host B analyzes and displays the
Syslog messages.

10
Figure 2 Network diagram for MAC information configuration
Configuration procedure
1. Configure Router to send Syslog messages to Host B.
For more information, see Network Management and Monitoring Configuration Guide.
2. Enable MAC information.
# Enable MAC information on Router.
<Router> system-view
[Router] mac-address information enable
# Configure MAC information mode as Syslog.
[Router] mac-address information mode syslog
# Enable MAC information on GigabitEthernet 4/0/1.
[Router] interface gigabitethernet 4/0/1
[Router-GigabitEthernet4/0/1] mac-address information enable added
[Router-GigabitEthernet4/0/1] mac-address information enable deleted
[Router-GigabitEthernet4/0/1] quit
# Set the MAC information queue length to 100.
[Router] mac-address information queue-length 100
# Set the interval for sending Syslog or trap messages to 20 seconds.
[Router] mac-address information interval 20

11
Ethernet link aggregation configuration
The SAP cards support the feature only when they work in Layer 2 mode.
The SAP cards can be installed on distributed routers only.
Ethernet link aggregation, or simply link aggregation, combines multiple physical Ethernet ports into one
logical link, called an aggregate link. Link aggregation delivers the following benefits:
•Increases bandwidth beyond the limits of any single link. In an aggregate link, traffic is distributed
across the member ports.
•Improves link reliability. The member ports back up one another dynamically. When a member port
fails, its traffic is switched to other member ports automatically.
As shown in Figure 3, Device A and Device B are connected by three physical Ethernet links. These
physical Ethernet links are combined into an aggregate link, Link aggregation 1. The bandwidth of this
aggregate link is as high as the total bandwidth of these three physical Ethernet links. At the same time,
the three Ethernet links back up one another.
Figure 3 Diagram for Ethernet link aggregation
Basic concepts
Aggregation group, member port, aggregate interface
Link aggregation is implemented through link aggregation groups. An aggregation group is a group of
Ethernet interfaces combined together, which are called member ports of the aggregation group. For
each aggregation group, a logical interface, called an aggregate interface, is created. To an upper layer
entity that uses the link aggregation service, a link aggregation group looks like a single logical link and
data traffic is transmitted through the aggregate interface.
Aggregate interfaces have the following types: BAGG interfaces, also called Layer 2 aggregate
interfaces, and RAGG interfaces, also called Layer 3 aggregate interfaces. When you create an
aggregate interface, the switch automatically creates an aggregation group of the same type and number
as the aggregate interface. For example, when you create interface Bridge-aggregation 1, Layer 2
aggregation group 1 is created.
Assign Layer 2 Ethernet interfaces only to a Layer 2 aggregation group, and Layer 3 Ethernet interfaces
only to a Layer 3 aggregation group.
On a Layer 3 aggregate interface, you can create subinterfaces. These subinterfaces are logical
interfaces that operate at the network layer. They can receive VLAN tagged packets for their Layer 3
aggregate interface.
The rate of an aggregate interface equals the total rate of its member ports in the selected state, and its
duplex mode is the same as the selected member ports. For more information about the states of member
ports in an aggregation group, see “Aggregation states of member ports in an aggregation group.”

12
Aggregation states of member ports in an aggregation group
A member port in an aggregation group can be in either of the following aggregation states:
•Selected: A selected port can forward user traffic.
•Unselected: An unselected port cannot forward user traffic.
Operational key
When aggregating ports, the system automatically assigns each port an operational key based on port
information such as port rate and duplex mode. Any change to this information triggers a recalculation of
the operational key.
In an aggregation group, all selected member ports are assigned the same operational key.
Configuration classes
Every configuration setting on a port may affect its aggregation state. Port configurations fall into the
following classes:
•Port attribute configurations, including port rate, duplex mode, and link status (up/down), which are
the most basic port configurations.
•Class-two configurations, as described in Table 1. A member port can be placed in the selected
state only if it has the same class-two configurations as the aggregate interface.
Table 1 Class-two configurations
Feature Considerations
Port isolation Whether the port has joined an isolation group, and the isolation group to
which the port belongs
QinQ
QinQ enable state (enable/disable), TPID for VLAN tags, outer VLAN tags to be
added, inner-to-outer VLAN priority mappings, inner-to-outer VLAN tag
mappings, inner VLAN ID substitution mappings
VLAN Permitted VLAN IDs, PVID, link type (trunk, hybrid, or access), IP subnet-based
VLAN configuration, protocol-based VLAN configuration, VLAN tagging mode
MAC address learning
MAC address learning capability, MAC address learning limit, forwarding of
frames with unknown destination MAC addresses after the MAC address
learning limit is reached
Class-two configurations made on an aggregate interface are automatically synchronized to all its
member ports. These configurations are retained on the member ports even after the aggregate interface
is removed.
Any class-two configuration change may affect the aggregation state of link aggregation member ports
and ongoing traffic. To make sure that you are aware of the risk, the system displays a warning message
every time you attempt to change a class-two configuration setting on a member port.
•Class-one configurations do not affect the aggregation state of the member port even if they are
different from those on the aggregate interface. GVRP and MSTP settings are examples of class-one
configurations.
The class-one configuration for a member port is effective only when the member port leaves the
aggregation group.

13
Reference port
When setting the aggregation state of the ports in an aggregation group, the system automatically picks
a member port as the reference port. A selected port must have the same port attributes and class-two
configurations as the reference port.
LACP
The IEEE 802.3ad LACP enables dynamic aggregation of physical links. It uses LACPDUs for exchanging
aggregation information between LACP-enabled devices.
1. LACP functions
Table 2 LACP functions
Category Description
Basic LACP functions
Implemented through the basic LACPDU fields, including the system LACP priority,
system MAC address, port aggregation priority, port number, and operational
key.
Each member port in a LACP-enabled aggregation group exchanges information
with its peer. When a member port receives an LACPDU, it compares the received
information with the information received on the other member ports. In this way
the two systems reach an agreement on which ports should be placed in the
selected state.
2. LACP priorities
LACP priorities have the following types: system LACP priority and port aggregation priority, as described
in Table 3.
Table 3 LACP priorities
T
yp
e Descri
p
tion Remarks
System LACP
priority
Used by two peer devices (or systems) to determine which one is
superior in link aggregation.
In dynamic link aggregation, the system that has higher system LACP
priority sets the selected state of member ports on its side first and
then the system that has lower priority sets port state accordingly.
The smaller the
priority value,
the higher the
priority
Port aggregation
priority
Determines the likelihood of a member port to be selected on a
system. The higher port aggregation priority, the higher likelihood.
3. LACP timeout interval
The LACP timeout interval specifies how long a member port waits to receive LACPDUs from the peer port.
If a local member port fails to receive LACPDUs from the peer within three times the LACP timeout interval,
the member port assumes that the peer port has failed. Configure the LACP timeout interval as the short
timeout interval (1 second) or the long timeout interval (30 seconds).