Allied Telesis AT-x900-12XT/S User manual

C613-16106-00 REV B www.alliedtelesis.com
AlliedWare PlusTM OS
How To |
Introduction
This How To Note introduces a number of commonly-used switching features of the
AlliedWare PlusTM operating system (OS), the next generation operating system for Allied
Telesis Inc’s high performance layer 3 managed switches:
zchanging port speed, duplex mode, and polarity
zVLANs
zRSTP and MSTP
zlink aggregation (static and using LACP)
zport mirroring
Contents
Introduction .............................................................................................................................................. 1
Contents ............................................................................................................................................ 1
Related How To Notes ................................................................................................................... 2
Which products and software version does it apply to? ........................................................ 2
Port Numbering ....................................................................................................................................... 3
Port numbers .................................................................................................................................... 3
Port ranges ........................................................................................................................................ 4
Port speed, duplex mode, and polarity .............................................................................................. 5
How to set the speed ..................................................................................................................... 5
How to set the duplex mode ........................................................................................................ 6
How to set the polarity .................................................................................................................. 6
Basic VLAN and IP configuration ......................................................................................................... 7
Configure Basic Switching Functionality

Page 2 | AlliedWare Plus™ OS How To Note: Switching
Introduction
Rapid Spanning Tree Protocol (RSTP) .............................................................................................. 12
The default configuration ............................................................................................................. 12
How to change the root bridge priority .................................................................................. 14
How to set ports as edge ports ................................................................................................. 14
Multiple Spanning Tree Protocol (MSTP) ......................................................................................... 15
Link Aggregation .................................................................................................................................... 21
How to configure Link Aggregation Control Protocol (LACP) .......................................... 21
How to configure static aggregation .......................................................................................... 24
Port mirroring ........................................................................................................................................ 25
Appendix: Complete configuration scripts ...................................................................................... 26
Script for VLAN example ............................................................................................................. 26
Script for MSTP example .............................................................................................................. 28
Related How To Notes
You also may find the following AlliedWare Plus OS How To Note useful:
How To Get Started With The AlliedWare PlusTM Operating System.
Which products and software version does it apply to?
This How To Note applies to the following Allied Telesis switches, running the
AlliedWare Plus OS software version 5.2.
1 or later:
zSwitchBlade x908
zx900 series

Page 3 | AlliedWare Plus™ OS How To Note: Switching
Port Numbering
Port Numbering
Port numbers
In the AlliedWare Plus OS, switch ports are named portx.y.z (e.g. port 1 .0. 1 ), where:
zthe first number (x) is the stack ID number
zthe second number (y) is the module number.
For ports on the base unit, the module number is 0.
For XEMs, the module numbering starts at
1 on the left-hand side of the switch when you
view the switch from the front, as the following figure shows for an x900 series switch:
For switches with multiple rows of XEMs, the numbering starts at the top left-hand corner,
as the following figure shows for a SwitchBlade x908:
The XEM bay number is printed on the top left-hand corner of each XEM bay.
zthe third number (z) is the port number.
PORT 2PORT 1 STACK
SELECT STATUS
ID
XEM-STK
FAULTNEGOTIATING LINK
PORT
STAT MEMBERMASTER
PORT 2PORT 1 STACK
SELECT STATUS
ID
XEM-STK
FAULTNEGOTIATING LINK
PORT
STAT MEMBERMASTER
XEM 1 XEM 2
XEM-12T
XEM-12T
ports-xems-x900.eps
AT-SBx908 Enhanced L3+ Modular Switch
SD
RESET
CONSOLEETH0 FAULT M ASTE R
STACKING SYSTEM POE
PORT 1 PORT 2 PSU 1 PSU 2 PSU 1 PSU 2
SwitchBlade
x908
1 2
6 7
3 4
8
XEM-12TXEM-12T XEM-12TXEM-12T XEM-12TXEM-12T XEM-12TXEM-12T
XEM 1 XEM 2 XEM 3 XEM 4
XEM 5 XEM 6 XEM 7 XEM 8
ports-xems-x908.eps

Page 4 | AlliedWare Plus™ OS How To Note: Switching
Port Numbering
Port ranges
Continuous To configure a continuous range of ports at the same time, enter the range in either of the
formats:
portx.y.z-portx.y.z
portx.y.z-x.y.z
For example, to configure the same interface setting on base switch ports 1 0-20, enter the
Global Configuration mode command:
awplus(config)#interface port1.0.10-1.0.20
Non-
continuous
To configure a non-continuous set of ports at the same time, enter the ports as a comma-
separated list, like this:
portx.y.z,portx.y.z
For example, to configure the same interface setting on base switch ports 1 and 5, enter the
Global Configuration mode command:
awplus(config)#interface port1.0.1,port1.0.5
You can combine a hyphen-separated range and a comma-separated list. For example, to
configure the same interface setting on base switch ports
1 -3 and 5, enter the Global
Configuration mode command:
awplus(config)#interface port1.0.1-1.0.3,port1.0.5

Page 5 | AlliedWare Plus™ OS How To Note: Switching
Port speed, duplex mode, and polarity
Port speed, duplex mode, and polarity
In most networks, you will not need to change the port speed, duplex mode, or polarity,
because the ports automatically negotiate suitable settings.
This section describes how to change them, if you need to.
Enter
Interface
mode
All three are interface settings, so you first enter Interface Configuration mode for the port
or port range you want to configure, by entering one of the commands:
awplus(config)#interface portx.y.z
awplus(config)#interface portx.y.z-x.y.z
The prompt changes to:
awplus(config-if)#
How to set the speed
The following table shows the speed options for each type of port.
To change the speed, first enter Interface Configuration mode for the port or port range you
want to configure. Then enter the command:
awplus(config-if)#speed <value>
For example, to set the speed of a tri-speed port to 1 00Mbps, enter the command:
awplus(config-if)#speed 100
To return the port to autonegotiating its speed, enter the command:
awplus(config-if)#speed auto
Port type Speed Options
non-SFP RJ-45 copper ports auto (the default)
1 0
1 00
1 000
supported tri-speed copper SFPs auto (the default)
1 0
1 00
1 000
1 00Mb fibre SFPs 1 00 (the default)
1 000Mb fibre SFPs auto (the default)
1 000
XFP modules auto (the default)
1 0000

Page 6 | AlliedWare Plus™ OS How To Note: Switching
Port speed, duplex mode, and polarity
How to set the duplex mode
By default, ports autonegotiate duplex mode (except for 1 00Base-FX ports which do not
support autonegotiation, so default to full duplex mode).
To change this, first enter Interface Configuration mode for the port or port range you want
to configure.
Then, to specify full duplex, enter the command:
awplus(config-if)#duplex full
To specify half duplex, enter the command:
awplus(config-if)#duplex half
To autonegotiate duplex mode, enter the command:
awplus(config-if)#duplex auto
How to set the polarity
By default, ports use auto MDI/MDI-X.
To change this, first enter Interface Configuration mode for the port or port range you want
to configure.
Then, to specify MDI, enter the command:
awplus(config-if)#polarity mdi
To specify MDI-X (crossover), enter the command:
awplus(config-if)#polarity mdix
To return to auto-detection, enter the command:
awplus(config-if)#polarity auto

Page 7 | AlliedWare Plus™ OS How To Note: Switching
Basic VLAN and IP configuration
Basic VLAN and IP configuration
This section configures a switch in a simple four-VLAN network, shown in the following
figure.
In this network, VLANs 2-4 span two switches. The section configures the left-hand switch in
the above figure. This switch is connected to a second switch via port
1 .0. 1 .
For the complete script for this example, see "Script for VLAN example" on page 26.
Enter Global Configuration mode and enter the command:
awplus(config)#vlan database
This puts you into VLAN mode. To create the VLANs, enter the commands:
awplus(config-vlan)#vlan 2 name vlan2
awplus(config-vlan)#vlan 3 name vlan3
awplus(config-vlan)#vlan 4 name vlan4
The AlliedWare Plus OS automatically enables new VLANs, and therefore adds the following
line to the running-config:
vlan 2-4 state enable
1. Create VLANs 2-4
Gateway:
192.168.1.254/24
vlan3:
192.168.3.1/24
vlan2:
192.168.2.1/24
1.0.3
1.0.2
1.0.4
vlan4:
192.168.4.1/24
vlan1:
192.168.1.1/24
port1.0.1
802.1Q trunked port:
vlan2, vlan3, vlan4
AlliedWare Plus
Switch
vlan2
vlan3
vlan4
vlans.eps

Page 8 | AlliedWare Plus™ OS How To Note: Switching
Basic VLAN and IP configuration
VLANs are configured as an attribute of switch ports. This means that you go into Interface
Configuration mode to configure the switch ports, and specify the VLANs you want to
associate with each switch port.
From Global Configuration mode, enter Interface Configuration mode by entering the
command:
awplus(config)#interface port1.0.1
Traffic for all three VLANs goes over port 1 .0. 1 , so next make
this port an 802.
1 Q trunk, by entering the command:
awplus(config-if)#switchport mode trunk
Finally, associate the port with the appropriate VLANs:
awplus(config-if)#switchport trunk allowed
vlan add 2-4
Note that by default the port’s native VLAN is VLAN 1 . The
native VLAN is the VLAN that the port uses for untagged
packets.
Change to configuring port
1 .0.2 by entering the command:
awplus(config-if)#interface port1.0.2
Associate vlan2 with the port, by entering the command:
awplus(config-if)#switchport access vlan 2
Ports in access mode send and receive untagged packets.
Similarly, associate vlan3 with port
1 .0.3, and vlan4 with port 1 .0.4, by entering the commands:
awplus(config-if)#interface port1.0.3
awplus(config-if)#switchport access vlan 3
awplus(config-if)#interface port1.0.4
awplus(config-if)#switchport access vlan 4
2. Associate the VLANs with port 1 .0. 1
3. Associate VLANs with ports 1 .0.2- 1 .0.3
Tip:
In the AlliedWare OS, we
add ports to VLANs as
tagged ports. In the
AlliedWare Plus OS, we
associate VLANs with a
trunk mode port. The port
behaviour is the same.
Tip:
You do not have to leave
Interface Configuration
mode to change interfaces.

Page 9 | AlliedWare Plus™ OS How To Note: Switching
Basic VLAN and IP configuration
Change to configuring vlan 1 by entering the command:
awplus(config-if)#interface vlan1
Assign the IP address and subnet by entering the command:
awplus(config-if)#ip address 192.168.1.1/24
Similarly, configure the other VLANs by entering the commands:
awplus(config-if)#interface vlan2
awplus(config-if)#ip address 192.168.2.1/24
awplus(config-if)#interface vlan3
awplus(config-if)#ip address 192.168.3.1/24
awplus(config-if)#interface vlan4
awplus(config-if)#ip address 192.168.4.1/24
Return to Global Configuration mode by entering the command:
awplus(config-if)#exit
Then enter the command:
awplus(config)#ip route 0.0.0.0/0 192.168.1.254
4. Assign IP addresses to the VLANs
5. Create a route to the default gateway

Page 10 | AlliedWare Plus™ OS How To Note: Switching
Basic VLAN and IP configuration
To check the configuration, first return to Privileged Exec mode by entering the command:
awplus(config)#exit
To see port membership and state for the VLANs, enter the command:
awplus#show vlan brief
The output looks like this:
To see the VLANs associated with each switch port, enter the command:
awplus#show interface switchport
The output looks like this:
6. Check the configuration
VLAN ID Name Type State Member ports
(u)-Untagged, (t)-Tagged
======= ================ ======= ======= ====================================
1 default STATIC ACTIVE port1.0.1(u) port1.0.5(u) port1.0.6(u)
port1.0.7(u) port1.0.8(u) port1.0.9(u)
port1.0.10(u) port1.0.11(u)
port1.0.12(u) port1.0.13(u)
port1.0.14(u) port1.0.15(u)
port1.0.16(u) port1.0.17(u)
port1.0.18(u) port1.0.19(u)
port1.0.20(u) port1.0.21(u)
port1.0.22(u) port1.0.23(u)
port1.0.24(u)
2 vlan2 STATIC ACTIVE port1.0.1(t) port1.0.2(u)
3 vlan3 STATIC ACTIVE port1.0.1(t) port1.0.3(u)
4 vlan4 STATIC ACTIVE port1.0.1(t) port1.0.4(u)
Interface name : port1.0.1
Switchport mode : trunk
Ingress filter : enable
Acceptable frame types : all
Default Vlan : 1
Configured Vlans : 1 2 3 4
Interface name : port1.0.2
Switchport mode : access
Ingress filter : enable
Acceptable frame types : all
Default Vlan : 2
Configured Vlans : 2
.
.
.

Page 11 | AlliedWare Plus™ OS How To Note: Switching
Basic VLAN and IP configuration
To see VLAN interface details, enter the command:
awplus# show interface | begin vlan
The output looks like this:
Interface vlan1
Scope: both
Link is UP, administrative state is UP
Hardware is VLAN, address is 0000.cd24.0331 (bia 0000.cd24.0331)
IPv4 address 192.168.1.1/24 broadcast 192.168.1.255
VRRP Master of : VRRP is not configured on this interface.
index 6 metric 1 mtu 1500
arp ageing timeout 300
<UP,BROADCAST,RUNNING,MULTICAST>
VRF Binding: Not bound
input packets 0, bytes 0, dropped 0, multicast packets 0
output packets 2, bytes 200, multicast packets 0 broadcast packets 0
Interface vlan2
Scope: both
Link is DOWN, administrative state is UP
Hardware is VLAN, address is 0000.cd24.0331 (bia 0000.cd24.0331)
IPv4 address 192.168.2.1/24 broadcast 192.168.2.255
VRRP Master of : VRRP is not configured on this interface.
index 7 metric 1 mtu 1500
arp ageing timeout 300
<UP,BROADCAST,MULTICAST>
VRF Binding: Not bound
input packets 0, bytes 0, dropped 0, multicast packets 0
output packets 0, bytes 0, multicast packets 0 broadcast packets 0
.
.
.

Page 12 | AlliedWare Plus™ OS How To Note: Switching
Rapid Spanning Tree Protocol (RSTP)
Rapid Spanning Tree Protocol (RSTP)
This example takes the network from "Basic VLAN and IP configuration" on page 7 and adds
two more switches in a ring topology, as the following figure shows. The switches use RSTP
to prevent layer 2 loops in the network.
The default configuration
RSTP is enabled with default settings on all switch ports. Therefore, no further configuration
is required for the above network.
The following figure shows the MAC addresses of each switch and the stable port states. By
default, all switches have the same root bridge priority, so the switch with the lowest MAC
address becomes the root bridge.
1.0.3
1.0.2
1.0.4
AlliedWare Plus
Switch
1.0.1
1.0.5 1.0.6
1.0.61.0.5
1.0.7 1.0.7
rstp.eps
1.0.3
1.0.2
1.0.4
AlliedWare Plus
Switch
1.0.1
1.0.5 1.0.6
1.0.61.0.5
1.0.7 1.0.7
root,
forwarding
designated,
forwarding
root,
forwarding
designated,
forwarding
alternate,
discarding
designated,
forwarding
MAC: 00-00-cd-24-03-31
00-00-cd-12-78-0800-00-cd-24-02-26
Root
bridge
rstp-port-state.eps

Page 13 | AlliedWare Plus™ OS How To Note: Switching
Rapid Spanning Tree Protocol (RSTP)
To see the STP state, enter Privileged Exec mode and enter the command:
awplus#show spanning-tree
The output looks like this:
Note that the Bridge ID is 80000000cd24033
1 , and that other IDs follow the same pattern.
This is made up of:
z8000—the switch’s root bridge priority in hexadecimal
z0000cd24033 1 —the switch’s MAC address.
% 1: Bridge up - Spanning Tree Enabled
% 1: Root Path Cost 200000 - Root Port 5006 - Bridge Priority 32768
% 1: Forward Delay 15 - Hello Time 2 - Max Age 20
% 1: Root Id 80000000cd127808
% 1: Bridge Id 80000000cd240331
% 1: last topology change Thu May 31 00:27:28 2007
% 1: portfast bpdu-filter disabled
% 1: portfast bpdu-guard disabled
% 1: portfast errdisable timeout disabled
% 1: portfast errdisable timeout interval 300 sec
%
.
.
.
%
% port1.0.5: Port 5005 - Id 838d - Role Alternate - State Discarding
% port1.0.5: Designated Path Cost 200000
% port1.0.5: Configured Path Cost 200000 - Add type Explicit ref count 1
% port1.0.5: Designated Port Id 838d - Priority 128 -
% port1.0.5: Root 80000000cd127808
% port1.0.5: Designated Bridge 80000000cd240226
% port1.0.5: Message Age 1 - Max Age 20
% port1.0.5: Hello Time 2 - Forward Delay 15
% port1.0.5: Forward Timer 0 - Msg Age Timer 0 - Hello Timer 1 - topo change timer 0
% port1.0.5: forward-transitions 2
% port1.0.5: Version Rapid Spanning Tree Protocol - Received RSTP - Send RSTP
% port1.0.5: No portfast configured - Current portfast off
% port1.0.5: portfast bpdu-guard default - Current portfast bpdu-guard off
% port1.0.5: portfast bpdu-filter default - Current portfast bpdu-filter off
% port1.0.5: no root guard configured - Current root guard off
% port1.0.5: Configured Link Type point-to-point - Current point-to-point
%
% port1.0.6: Port 5006 - Id 838e - Role Rootport - State Forwarding
% port1.0.6: Designated Path Cost 0
% port1.0.6: Configured Path Cost 200000 - Add type Explicit ref count 1
% port1.0.6: Designated Port Id 8006 - Priority 128 -
% port1.0.6: Root 80000000cd127808
% port1.0.6: Designated Bridge 80000000cd127808
% port1.0.6: Message Age 1 - Max Age 20
% port1.0.6: Hello Time 2 - Forward Delay 15
% port1.0.6: Forward Timer 0 - Msg Age Timer 5 - Hello Timer 1 - topo change timer 0
% port1.0.6: forward-transitions 3
% port1.0.6: Version Rapid Spanning Tree Protocol - Received RSTP - Send RSTP
% port1.0.6: No portfast configured - Current portfast off
% port1.0.6: portfast bpdu-guard default - Current portfast bpdu-guard off
% port1.0.6: portfast bpdu-filter default - Current portfast bpdu-filter off
% port1.0.6: no root guard configured - Current root guard off
% port1.0.6: Configured Link Type point-to-point - Current point-to-point

Page 14 | AlliedWare Plus™ OS How To Note: Switching
Rapid Spanning Tree Protocol (RSTP)
How to change the root bridge priority
The default root bridge priority is 32768 (8000 in hexadecimal). When all switches have the
same priority, the switch with the lowest MAC address becomes the root bridge.
If you want the AlliedWare Plus switch to be the root bridge, you can do this by setting the
priority to a value lower than 32768. For example, to set the priority value to 8
1 92, enter
Global Configuration mode and enter the command:
awplus(config)#spanning-tree priority 8192
Enter priority as a decimal value. It is in increments of 4096. If you enter a number that is not
a multiple of 4096, the switch rounds the number down.
The following figure shows the new port states after the priority change.
How to set ports as edge ports
In this example’s network, ports 1 .0.2, 1 .0.3, and 1 .0.4 are attached to devices that cannot
generate BPDUs (such as workstations) and therefore should be RSTP edge ports.
To set them as edge ports, enter Global Configuration mode and enter the commands:
awplus(config)#interface port1.0.2-1.0.4
awplus(config-if)#spanning-tree edgeport
1.0.3
1.0.2
1.0.4
AlliedWare Plus Switch:
Root bridge
1.0.1
1.0.5 1.0.6
1.0.61.0.5
1.0.7 1.0.7
designated,
forwarding
root,
forwarding
designated,
forwarding
root,
forwarding
MAC: 00-00-cd-24-03-31
Root bridge priority: 8192
00-00-cd-24-02-26
Root bridge priority: 32768
00-00-cd-12-78-08
Root bridge priority: 32768
alternate,
discarding
designated,
forwarding
rstp-priority.eps

Page 15 | AlliedWare Plus™ OS How To Note: Switching
Multiple Spanning Tree Protocol (MSTP)
Multiple Spanning Tree Protocol (MSTP)
This example takes the looped network from "Rapid Spanning Tree Protocol (RSTP)" on
page 12 and configures MSTP instead of RSTP. MSTP lets you block different VLANs at
different points in the network. This gives you greater control over the flow of traffic in your
network, and allows more efficient use of bandwidth by using more switch ports.
As the following figure shows, this example discards traffic for:
zvlans 2 and 3 between the AlliedWare Plus switch and Switch 2
zvlan 4 between Switches 2 and 3
For the complete script for this example, see "Script for MSTP example" on page 28.
Enter Global Configuration mode and enter the command:
awplus(config)#vlan database
This puts you into VLAN mode. To create the VLANs, enter the commands:
awplus(config-vlan)#vlan 2 name vlan2
awplus(config-vlan)#vlan 3 name vlan3
awplus(config-vlan)#vlan 4 name vlan4
1. Create the VLANs
1.0.3
1.0.2
1.0.4
AlliedWare Plus
Switch
1.0.5 1.0.6
1.0.61.0.5
1.0.7 1.0.7
vlan2
vlan3
vlan4
vlan2
vlan3
vlan4
vlan2
vlan3
vlan4
Root bridge for
instance 2.
(priority = 8192)
instance 2
instance 1
discarding
for vlan 4,
instance 2
discarding
for vlans 2-3,
instance 1
Switch 2 Switch 3
Root bridge for
instance 1
mstp.eps

Page 16 | AlliedWare Plus™ OS How To Note: Switching
Multiple Spanning Tree Protocol (MSTP)
Ports 1 .0.2- 1 .0.4 are in access mode. Enter the commands:
awplus(config-vlan)#interface port1.0.2
awplus(config-if)#switchport access vlan 2
awplus(config-if)#interface port1.0.3
awplus(config-if)#switchport access vlan 3
awplus(config-if)#interface port1.0.4
awplus(config-if)#switchport access vlan 4
Ports 1 .0.5- 1 .0.6 are in trunk mode. Enter the commands:
awplus(config-if)#interface port1.0.5-1.0.6
awplus(config-if)#switchport mode trunk
awplus(config-if)#switchport trunk allowed vlan add 2-4
Note that by default the port’s native VLAN—the VLAN that the port uses for untagged
packets—is VLAN
1 . Some control packets are untagged, including MSTP CIST BPDUs.
Leave Interface Configuration mode by entering the command:
awplus(config-if)#exit
Enter Global Configuration mode and enter the command:
awplus(config)#spanning-tree mode mstp
Enter MST mode by entering the command:
awplus(config)#spanning-tree mst configuration
To allow MSTP to block different VLANs at different places in the loop, create two instances.
Enter the commands:
awplus(config-mst)#instance 1 vlan 2-3
awplus(config-mst)#instance 2 vlan 4
Specify the MSTP region and revision number. Enter the commands:
awplus(config-mst)#region awplus
awplus(config-mst)#revision 1
Note that all MSTP devices in this network must have the same region and revision number.
2. Associate VLANs with ports
3. Select MSTP as the spanning tree mode
4. Configure MST instances, region, and revision number

Page 17 | AlliedWare Plus™ OS How To Note: Switching
Multiple Spanning Tree Protocol (MSTP)
Enter Interface Configuration mode for the trunk ports 1 .0.5- 1 .0.6 by entering the command:
awplus(config-mst)#interface port1.0.5-1.0.6
Attach the instances to these ports by entering the commands:
awplus(config-if)#spanning-tree mst instance 1
awplus(config-if)#spanning-tree mst instance 2
Attach the appropriate instance to each access port by entering the commands:
awplus(config-if)#interface port1.0.2-1.0.3
awplus(config-if)#spanning-tree mst instance 1
awplus(config-if)#interface port1.0.4
awplus(config-if)#spanning-tree mst instance 2
MSTP lets you distribute traffic more efficiently across the network by blocking different links
for different VLANs. You do this by making separate switches into the root bridge for each
MSTP instance, so that each MSTP instance blocks a different link.
The configuration described in the previous steps blocks port
1 .0.5 on the AlliedWare Plus
switch for traffic for all the VLANs. This is because both instances have the same root bridge.
To block traffic between Switches 2 and 3, we change the priority of the AlliedWare Plus
switch, so that it becomes the root bridge. We only want this to happen for traffic in vlan4,
so we only change the priority for instance 2.
To do this, first enter MSTP mode by entering the command:
awplus(config-if)#spanning-tree mst configuration
Then set the priority by entering the command:
awplus(config-mst)#instance 2 priority 8192
In this example’s network, you can get the desired behaviour by setting the priority to any
number lower than the default of 32768.
5. Associate the instances with the appropriate switch ports
6. Force the AlliedWare Plus switch to be the root bridge for instance 2

Page 18 | AlliedWare Plus™ OS How To Note: Switching
Multiple Spanning Tree Protocol (MSTP)
To check for general information about MSTP, and the CIST settings, enter Privileged Exec
mode and enter the command:
awplus#show spanning-tree
The output shows that Switch 3 is the CIST root bridge:
7. Check the configuration
% 1: Bridge up - Spanning Tree Enabled
% 1: CIST Root Path Cost 0 - CIST Root Port 5006 - CIST Bridge Priority 32768
% 1: Forward Delay 15 - Hello Time 2 - Max Age 20 - Max-hops 20
% 1: CIST Root Id 80000000cd127808
% 1: CIST Reg Root Id 80000000cd127808
% 1: CIST Bridge Id 80000000cd240331
% 1: portfast bpdu-filter disabled
% 1: portfast bpdu-guard disabled
% 1: portfast errdisable timeout disabled
% 1: portfast errdisable timeout interval 300 sec
.
.
.
% port1.0.5: Port 5005 - Id 838d - Role Alternate - State Discarding
% port1.0.5: Designated External Path Cost 0 -Internal Path Cost 200000
% port1.0.5: Configured Path Cost 20000 - Add type Explicit ref count 3
% port1.0.5: Designated Port Id 8005 - CIST Priority 128 -
% port1.0.5: CIST Root 80000000cd127808
% port1.0.5: Regional Root 80000000cd127808
% port1.0.5: Designated Bridge 80000000cd240226
% port1.0.5: Message Age 0 - Max Age 20
% port1.0.5: CIST Hello Time 2 - Forward Delay 15
% port1.0.5: CIST Forward Timer 0 - Msg Age Timer 4 - Hello Timer 0 - topo change
timer 0
% port1.0.5: forward-transitions 1
% port1.0.5: Version Multiple Spanning Tree Protocol - Received MSTP - Send MSTP
% port1.0.5: No portfast configured - Current portfast off
% port1.0.5: portfast bpdu-guard default - Current portfast bpdu-guard off
% port1.0.5: portfast bpdu-filter default - Current portfast bpdu-filter off
% port1.0.5: no root guard configured - Current root guard off
% port1.0.5: Configured Link Type point-to-point - Current point-to-point
.
.
.

Page 19 | AlliedWare Plus™ OS How To Note: Switching
Multiple Spanning Tree Protocol (MSTP)
To check for the state of each port for each instance, enter Privileged Exec mode and enter
the command:
awplus#show spanning-tree mst instance <value> interface port<value>
For instance 1 and port 1 .0.5—vlan2 and vlan3—the output shows that Switch 3 is the
MSTI root bridge and that the port is discarding packets:
For instance 2 and port
1 .0.5—vlan4—the output shows that the AlliedWare Plus switch
is the MSTI root bridge and that the port is forwarding packets:
awplus#show spanning-tree mst instance 1 interface port1.0.5
% 1: MSTI Root Path Cost 200000 - MSTI Root Port 5006 - MSTI Bridge Priority 32768
% 1: MSTI Root Id 80010000cd127808
% 1: MSTI Bridge Id 80010000cd240331
% port1.0.5: Port 5005 - Id 838d - Role Alternate - State Discarding
% port1.0.5: Designated Internal Path Cost 200000 - Designated Port Id 8005
% port1.0.5: Configured Internal Path Cost 20000
% port1.0.5: Configured CST External Path cost 20000
% port1.0.5: CST Priority 128 - MSTI Priority 128
% port1.0.5: Designated Root 80010000cd127808
% port1.0.5: Designated Bridge 80010000cd240226
% port1.0.5: Message Age 0 - Max Age 0
% port1.0.5: Hello Time 2 - Forward Delay 15
% port1.0.5: Forward Timer 0 - Msg Age Timer 4 - Hello Timer 1
awplus#show spanning-tree mst instance 2 interface port1.0.5
% 1: MSTI Root Path Cost 0 - MSTI Root Port 0 - MSTI Bridge Priority 8192
% 1: MSTI Root Id 20020000cd240331
% 1: MSTI Bridge Id 20020000cd240331
% port1.0.5: Port 5005 - Id 838d - Role Designated - State Forwarding
% port1.0.5: Designated Internal Path Cost 0 - Designated Port Id 838d
% port1.0.5: Configured Internal Path Cost 20000
% port1.0.5: Configured CST External Path cost 20000
% port1.0.5: CST Priority 128 - MSTI Priority 128
% port1.0.5: Designated Root 20020000cd240331
% port1.0.5: Designated Bridge 20020000cd240331
% port1.0.5: Message Age 0 - Max Age 0
% port1.0.5: Hello Time 2 - Forward Delay 15
% port1.0.5: Forward Timer 0 - Msg Age Timer 0 - Hello Timer 1

Page 20 | AlliedWare Plus™ OS How To Note: Switching
Multiple Spanning Tree Protocol (MSTP)
For instance 1 and port 1 .0.6—vlan2 and vlan3—the output shows that the port is
forwarding packets. The port role is rootport, indicating that it is the shortest path to the root
bridge for the AlliedWare Plus switch.
For instance 2 and port
1 .0.6—vlan4—the output shows that the port is forwarding
packets:
awplus#show spanning-tree mst instance 1 interface port1.0.6
% 1: MSTI Root Path Cost 200000 - MSTI Root Port 5006 - MSTI Bridge Priority 32768
% 1: MSTI Root Id 80010000cd127808
% 1: MSTI Bridge Id 80010000cd240331
% port1.0.6: Port 5006 - Id 838e - Role Rootport - State Forwarding
% port1.0.6: Designated Internal Path Cost 0 - Designated Port Id 8006
% port1.0.6: Configured Internal Path Cost 200000
% port1.0.6: Configured CST External Path cost 200000
% port1.0.6: CST Priority 128 - MSTI Priority 128
% port1.0.6: Designated Root 80010000cd127808
% port1.0.6: Designated Bridge 80010000cd127808
% port1.0.6: Message Age 0 - Max Age 0
% port1.0.6: Hello Time 2 - Forward Delay 15
% port1.0.6: Forward Timer 0 - Msg Age Timer 5 - Hello Timer 1
awplus#show spanning-tree mst instance 2 interface port1.0.6
% 1: MSTI Root Path Cost 0 - MSTI Root Port 0 - MSTI Bridge Priority 8192
% 1: MSTI Root Id 20020000cd240331
% 1: MSTI Bridge Id 20020000cd240331
% port1.0.6: Port 5006 - Id 838e - Role Designated - State Forwarding
% port1.0.6: Designated Internal Path Cost 0 - Designated Port Id 838e
% port1.0.6: Configured Internal Path Cost 200000
% port1.0.6: Configured CST External Path cost 200000
% port1.0.6: CST Priority 128 - MSTI Priority 128
% port1.0.6: Designated Root 20020000cd240331
% port1.0.6: Designated Bridge 20020000cd240331
% port1.0.6: Message Age 0 - Max Age 0
% port1.0.6: Hello Time 2 - Forward Delay 15
% port1.0.6: Forward Timer 0 - Msg Age Timer 0 - Hello Timer 0