H3C S9800 Series User manual

H3C S9800 Switch Series
EVI Configuration Guide
Hangzhou H3C Technologies Co., Ltd.
http://www.h3c.com
Software version: Release 213x
Document version: 6W101-20151130

Copyright ©2015, Hangzhou H3C Technologies Co., Ltd. and its licensors
All rights reserved
No part of this manual may be reproduced or transmitted in any form or by any means without prior
written consent of Hangzhou H3C Technologies Co., Ltd.
Trademarks
H3C, , H3CS, H3CIE, H3CNE, Aolynk, , H3Care, , IRF, NetPilot, Netflow,
SecEngine, SecPath, SecCenter, SecBlade, Comware, ITCMM and HUASAN are trademarks of
Hangzhou H3C Technologies Co., Ltd.
All other trademarks that may be mentioned in this manual are the property of their respective owners.
Notice
The information in this document is subject to change without notice. Every effort has been made in the
preparation of this document to ensure accuracy of the contents, but all statements, information, and
recommendations in this document do not constitute the warranty of any kind, express or implied.

Preface
The H3C S9800 documentation set includes 17 configuration guides. These guides describe the
software features for the H3C S9800 Switch Series running Release 2135 and later, and guide you
through the software configuration procedures. These guides also provide configuration examples to
help you apply software features to different network scenarios.
The EVI Configuration Guide describes the application scenarios, fundamentals, and configuration of
EVI.
This preface includes:
•Audience
•Conventions
•Obtaining documentation
•Technical support
•Documentation feedback
Audience
This documentation is intended for:
•Network planners
•Field technical support and servicing engineers
•Network administrators working with the S9800 series
Conventions
This section describes the conventions used in this documentation set.
Command conventions
Convention Descri
p
tion
Boldface Bold text represents commands and keywords that you enter literally as shown.
Italic Italic text represents arguments that you replace with actual values.
[ ] Square brackets enclose syntax choices (keywords or arguments) that are optional.
{ x | y | ... }
Braces enclose a set of required syntax choices separated by vertical bars, from which
you select one.
[ x | y | ... ]
Square brackets enclose a set of optional syntax choices separated by vertical bars, from
which you select one or none.
{ x | y | ... } *
Asterisk marked braces enclose a set of required syntax choices separated by vertical
bars, from which you select at least one.
[ x | y | ... ] *
Asterisk marked square brackets enclose optional syntax choices separated by vertical
bars, from which you select one choice, multiple choices, or none.

Convention Descri
p
tion
&<1-n> The argument or keyword and argument combination before the ampersand (&) sign can
be entered 1 to n times.
# A line that starts with a pound (#) sign is comments.
GUI conventions
Convention Descri
p
tion
Boldface Window names, button names, field names, and menu items are in Boldface. For
example, the New User window appears; click OK.
> Multi-level menus are separated by angle brackets. For example, File > Create > Folder.
Symbols
Convention Descri
p
tion
WARNING An alert that calls attention to important information that if not understood or followed can
result in personal injury.
CAUTION An alert that calls attention to important information that if not understood or followed can
result in data loss, data corruption, or damage to hardware or software.
IMPORTANT An alert that calls attention to essential information.
NOTE An alert that contains additional or supplementary information.
TIP An alert that provides helpful information.
Network topology icons
Represents a generic network device, such as a router, switch, or firewall.
Represents a routing-capable device, such as a router or Layer 3 switch.
Represents a generic switch, such as a Layer 2 or Layer 3 switch, or a router that supports
Layer 2 forwarding and other Layer 2 features.
Represents an access controller, a unified wired-WLAN module, or the access controller
engine on a unified wired-WLAN switch.
Represents an access point.
Represents a mesh access point.
Represents omnidirectional signals.
Represents directional signals.




Represents a security product, such as a firewall, UTM, multiservice security gateway, or
load-balancing device.
Represents a security card, such as a firewall, load-balancing, NetStream, SSL VPN, IPS,
or ACG card.
Port numbering in examples
The port numbers in this document are for illustration only and might be unavailable on your device.
Obtaining documentation
Access the most up-to-date H3C product documentation on the World Wide Web
at http://www.h3c.com.
Click the following links to obtain different categories of product documentation:
[Technical Documents]—Provides hardware installation, software upgrading, and software feature
configuration and maintenance documentation.
[Products & Solutions]—Provides information about products and technologies, as well as solutions.
[Software Download]—Provides the documentation released with the software version.
Technical support
servic[email protected]
http://www.h3c.com
Documentation feedback
You can e-mail your comments about product documentation to [e-mail].
We appreciate your comments.


i
Contents
Configuring EVI ···························································································································································· 1
Overview············································································································································································1
Layer 2 connectivity extension issues ·····················································································································1
Network topologies··················································································································································2
Terminology ······························································································································································3
Working mechanism················································································································································4
Selective flooding ·····················································································································································6
Path MTU···································································································································································7
Licensing requirements······················································································································································7
Prerequisites·······································································································································································7
EVI configuration task list ·················································································································································7
Configuring EVI basic functions·······································································································································8
Configuring a site ID················································································································································8
Configuring an EVI tunnel ·······································································································································8
Assigning a network ID to the EVI tunnel···············································································································9
Specifying extended VLANs on the EVI tunnel······································································································9
Configuring ENDP················································································································································· 10
Enabling EVI on transport-facing physical interfaces ························································································ 11
Tuning EVI IS-IS parameters ·········································································································································· 12
EVI IS-IS configuration task list ····························································································································· 12
Creating an EVI IS-IS process······························································································································· 12
Optimizing an EVI IS-IS network·························································································································· 13
Specifying a routing policy for an EVI IS-IS process·························································································· 16
Enabling adjacency change logging ·················································································································· 16
Configuring SNMP notifications and context for EVI IS-IS················································································ 17
Configuring Graceful Restart for an EVI IS-IS process······················································································· 17
Increasing the maximum number of MAC entries in an LSP for an EVI IS-IS process ···································· 18
Enabling EVI flooding for all destination-unknown frames ························································································ 18
Enabling selective flooding for a MAC address········································································································· 19
Enabling MAC address learning at the ingress·········································································································· 19
Displaying and maintaining EVI··································································································································· 20
EVI configuration examples ·········································································································································· 21
EVI network configuration example····················································································································· 21
Multiple-EVI-networks configuration example····································································································· 26
Index ···········································································································································································30

1
Configuring EVI
Overview
Ethernet Virtual Interconnect (EVI) is a MAC-in-IP technology that provides Layer 2 connectivity between
distant Layer 2 network sites across an IP routed network. It is used for connecting geographically
dispersed sites of a virtualized large-scale data center that requires Layer 2 adjacency (see Figure 1).
EVI enables long-distance virtual machine workload mobility and data mobility, disaster recovery, and
business continuity. For example, virtual machines can move between data center sites without changing
their IP addresses, so their movements are transparent to users and do not disrupt traffic.
Figure 1 Virtual machine migration
Layer 2 connectivity extension issues
EVI resolves the following Layer 2 connectivity extension issues:
•Site independence—EVI keeps protocol failures, such as broadcast storms, from propagating
across sites.
•Transport independence—EVI has no special requirements for site location or transport network
type, except that the transport network can forward IP packets.
•Link efficiency—EVI optimizes the inter-site multicast and broadcast transmission mechanism and
implements load-sharing on redundant links.
•Site and transport transparency—EVI is both site and transport network transparent. It has no
special site or transport network topology requirements.

2
•Easy management and maintenance—EVI requires deployment only on edge devices and does not
introduce any topology change or configuration within sites or the transport network.
Network topologies
As shown in Figure 2, an EVI network has one edge device at each site. These sites are connected
through virtual links and run the EVI IS-IS protocol to advertise their MAC address entries to each other.
EVI maintains MAC routing information on the edge devices without changing the forwarding or routing
information within the sites or the transport network.
Figure 2 EVI network
EVI supports multiple EVI networks on an edge device for extending different VLANs across the Layer 3
network. One EVI network can convey multiple VLANs, but one VLAN can map to only one EVI network.
Each EVI network has separate network parameters and independently forwards traffic.
As shown in Figure 3, EVI network 1 extends VLAN 100 and VLAN 101 to Site 2, Site 3, and Site 4 for
Web access traffic. EVI network 2 extends VLAN 4000 (the management VLAN) to all sites, and EVI
network 3 extends VLANs 50 to 80 between Site 1 and Site 4 for database traffic.
Transport network Site network
Edge
device
EVI link
EVI
Site network
Edge device
Site
network
Edge device
EVI link EVI link VLAN 10
VLAN 10
VLAN 10
Site 1
Site 2
Site 3

3
Figure 3 Multiple EVI networks
Terminology
Edge device
An edge device performs typical Layer 2 learning and forwarding on the site-facing interfaces (internal
interfaces) and performs tunneling and routing on the transport-facing interfaces.
EVI network ID
An edge device can belong to multiple EVI networks. Each EVI network is uniquely identified by a
network ID.
EVI link
An EVI link is a bidirectional virtual Ethernet channel between a pair of edge devices in an EVI network.
EVI links are conveyed on EVI tunnels. Each EVI link is uniquely identified by a pair of source and
destination EVI tunnel IP addresses.
EVI tunnel
An EVI tunnel is a point-to-many automatic GRE tunnel that conveys EVI links for an EVI network. One EVI
tunnel can provide services only for one EVI network.
EVI neighbor
All edge devices in an EVI network are EVI neighbors to one other.
ENDP
EVI Neighbor Discovery Protocol uses the client/server model to dynamically discover sites and edge
devices, establish and maintain EVI links, and exchange network membership information in an EVI
network.
ENDS
An EVI neighbor discovery server maintains all neighbor information in an EVI network. An EVI network
can have up to two ENDSs.
Site 1
Site 2
Site 4
Site 5
EVI 1
VLANs 100-101
EVI 2
VLAN 4000
EVI 3
VLANs 50-80
Site 3

4
ENDC
An EVI neighbor discovery client works with an ENDS to learn neighbor information and triggers EVI link
setup between neighbors.
EVI IS-IS
EVI IS-IS establishes adjacencies and advertises MAC reachability information among edge devices at
different sites in an EVI network.
EVI IS-IS runs independently of the Layer 3 routing protocols on the transport network and sites.
DED
An inter-site DED is elected from between the edge devices on each EVI link to send CSNP packets for
LSDB synchronization.
Internal interface
Internal interfaces are site-facing Layer 2 interfaces that connect an edge device to switches or routers in
the site.
Working mechanism
An edge device uses the following process to set up an EVI network and forward traffic at Layer 2 to
remote sites:
1. Runs ENDP to discover EVI neighbors and set up EVI links between neighbors.
2. Runs EVI IS-IS to advertise MAC reachability information over EVI links in the EVI network.
3. Forwards traffic based on MAC reachability information that has been received from other sites.
This section describes this process in detail.
Neighbor discovery
An EVI network runs ENDP to discover all its edge devices and establishes adjacencies among the edge
devices in the following process:
1. ENDS is enabled on one edge device, and ENDC is enabled on all other edge devices.
2. The ENDCs register their IP addresses and other data with the ENDS.
3. The ENDS updates its ENDC database with received data and sends the updated database to
each ENDC.
4. After receiving the register reply, the ENDCs establish an EVI link with each other.
For high availability, you can configure up to two ENDSs for an EVI network.
MAC address learning
MAC reachability information on an EVI edge device comes from the following sources:
•MAC entries configured or learned in the data plane—The edge devices use the typical
source-MAC-based learning mechanism to learn unicast MAC addresses in their local sites (called
"local MAC addresses").
•MAC entries learned through EVI IS-IS—After completing neighbor discovery, the edge devices run
EVI IS-IS in the control plane to establish adjacencies and advertise MAC reachability information
that has been learned or configured in the data plane to each other over EVI links.

5
NOTE:
The mac-address max-mac-count command and the mac-address mac-learning enable command take
effect only on local MAC addresses, which are learned in the data plane. They do not take effect on
remote MAC addresses, which are learned in the control plane.
Unicast flow
For intra-site unicast flows, an edge device performs the typical MAC address table lookup, as shown
in Figure 4.
Figure 4 Layer 2 forwarding in a site
The following forwarding process (see Figure 5) takes place for unicast flows between sites:
1. The source edge device learns the source MAC address of the incoming Ethernet frame, and looks
up the destination MAC address in its MAC table for the outgoing interface.
2. If the outgoing interface is an EVI-Link interface instead of a physical port, the source edge device
encapsulates the frame in a GRE header, and then adds an IP header and a link layer protocol
header.
In the outer IP header, the source IP address is the source edge device's tunnel source IP address,
and the destination IP address is the destination edge device's tunnel source IP address.
3. The source edge device forwards the encapsulated packet out of the EVI link to the destination
edge device across the IP transport network.
4. The destination edge device removes the headers of the original Ethernet frame, looks up the
destination MAC address in the MAC address table, and sends the frame out of the matching
outgoing interface.
EVI
Site 1
EVI
Site 2
MAC table
VLAN MAC Interface
200 MAC1 XGE1/0/1
200 MAC2 XGE1/0/2
MAC1 MAC2
EVI
Transport network
XGE1/0/1 XGE1/0/2
Host A Host B

6
Figure 5 Layer 2 forwarding between sites
Flooding flow
An edge device handles flooding by frame type, as follows:
•Broadcast frame—Floods the frame to all interfaces in the VLAN where the frame has been
received, including internal interfaces and EVI-Link interfaces.
•Destination-unknown unicast or multicast frame—Floods the frame to all internal interfaces in the
VLAN where the frame has been received. The edge device typically does not forward
destination-unknown frames to other sites. If a site-to-site flooding is desirable for a special MAC
address, use the selective flooding feature (see "Selective flooding").
To flood a frame to remote sites, an EVI edge device must replicate the frame, encapsulate each replica
in one unicast frame for each destination site, and send the unicast frames to the remote edge devices.
Selective flooding
Selective flooding enables an edge device to send an unknown unicast or multicast frame out of an EVI
tunnel interface.
This feature is designed for special multicast addresses that require flooding across sites but cannot be
added to a multicast forwarding table by IGMP snooping.
For example, you must configure selective flooding for PIM hellos, IGMP general query packets, and
Microsoft NLBS cluster traffic to be sent out of an EVI tunnel interface.

7
Path MTU
When encapsulating an Ethernet frame in EVI, the edge device does not modify the Ethernet frame, but
it sets the DF bit in the IP header. For an Ethernet transport network, the total size of an EVI protocol
packet increases by 46 bytes, and the total size of a data packet increases by 38 bytes. Because EVI
does not support path MTU discovery, your EVI deployment must make sure the path MTU of the
transport network is higher than the maximum size of EVI tunneled frames.
Licensing requirements
EVI requires a license. For information about feature licensing, see Fundamentals Configuration Guide.
Prerequisites
Before you can configure EVI, you must perform the following tasks:
1. Set the system operating mode to advanced by using the system-working-mode advance
command.
2. Save the configuration.
3. Delete the binary .mdb next-startup configuration file.
4. Reboot the device.
For more information about setting the system operating mode, see device management in Fundamentals
Configuration Guide.
EVI configuration task list
Perform the following tasks on all edge devices of an EVI network:
Tasks at a glance Remarks
Configuring EVI basic functions:
(Optional.) Configuring a site ID
(Required.) Configuring an EVI tunnel:
•(Required.) Assigning a network ID to the EVI tunnel
•(Required.) Specifying extended VLANs on the EVI tunnel
•(Required.) Configuring ENDP
•(Optional.) Enabling EVI on transport-facing physical interfaces
An EVI tunnel can provide services
for only one EVI network.
All edge devices in an EVI network
must have the same network ID.
An extended VLAN can be
assigned only to one EVI network.
(Optional.) Tuning EVI IS-IS parameters
EVI IS-IS automatically runs on an
EVI tunnel interface immediately
after the interface is created.
You can tune EVI IS-IS parameters
for optimizing network
performance.
(Optional.) Enabling EVI flooding for all destination-unknown frames
Perform this task to flood frames
with unknown MAC addresses to
the EVI tunnel interface.

8
Tasks at a glance Remarks
(Optional.) Enabling selective flooding for a MAC address
Perform this task for special
multicast MAC addresses that
require Layer 2 inter-site forwarding
but cannot be learned into the MAC
address table.
(Required.) Enabling MAC address learning at the ingress Perform this task to ensure correct
MAC address learning.
Configuring EVI basic functions
Except for configuring the site ID and enabling the EVI feature, all tasks in this section are required for
setting up an EVI network.
Configuring a site ID
By default, all edge devices in an EVI network have a site ID of 0. To identify the site of each edge device,
you can change their site IDs.
Manually assigned site IDs must be unique in the EVI network. If the edge devices at two sites are
assigned the same site ID, EVI IS-IS isolates the device with the lower MAC address. The isolated device
can only receive EVI IS-IS hello packets. It cannot exchange EVI IS-IS packets with its neighbors. To
identify isolated devices, use the display evi isis brief command or the display evi isis peer command.
NOTE:
EVI IS-IS does not perform isolation for edge devices that use the default site ID.
To assign a site ID to the device:
Step Command Remarks
1. Enter system view. system-view N/A
2. Assign a site ID to the
device. evi site-id site-id The default site ID is 0.
Configuring an EVI tunnel
Step Command Remarks
1. Enter system view. system-view N/A
2. Create an EVI tunnel
interface and enter tunnel
interface view.
interface tunnel number mode evi
By default, no tunnel interface exists.
The endpoints of a tunnel must use the
same tunnel mode.

9
Step Command Remarks
3. Specify a source IP address
or interface for the tunnel.
source { ipv4-address |
interface-type interface-number }
By default, no source IP address or
source interface is specified for any
tunnel.
The source interface can be a Layer 3
Ethernet interface, Layer 3 aggregate
interface, VLAN interface, or Layer 3
loopback interface.
EVI uses the specified address or the
primary IP address of the specified
source interface as the source IP
address of tunneled packets on the
transport network.
EVI networks can share a tunnel
source IP address or interface.
4. Configure the EVI link
keepalive interval and the
maximum number of
keepalive transmissions.
keepalive [ seconds [ times ] ]
By default, a keepalive packet is sent
every five seconds and the maximum
number of transmissions is two.
If no reply is received from the remote
end on an EVI link after the maximum
number of keepalive transmissions is
reached, the local end considers the
EVI link as having failed.
5. (Optional.) Generate a GRE
key for tunneled packets
based on their VLAN IDs.
gre key vlan-id
By default, EVI tunneled packets do
not contain a GRE key.
The GRE key setting must be the same
across an EVI network. Perform this
step if any remote edge devices
generate VLAN ID-based GRE keys
for EVI tunneled packets.
Assigning a network ID to the EVI tunnel
Assign the same network ID to the EVI tunnels of all edge devices in an EVI network.
On an edge device, the network ID assigned to an EVI tunnel must be unique.
To assign a network ID to an EVI tunnel:
Step Command Remarks
1. Enter system view. system-view N/A
2. Enter tunnel interface view. interface tunnel number
[ mode evi ] N/A
3. Specify a network ID. evi network-id number By default, no network ID is specified.
Specifying extended VLANs on the EVI tunnel
When configuring extended VLANs, follow these guidelines:

10
•An extended VLAN can be specified only on one EVI tunnel.
•To avoid loops, do not assign transport-facing ports to extended VLANs.
•To avoid data breach, make sure all edge devices in an EVI network maintain the same list of
extended VLANs.
To assign extended VLANs to an EVI tunnel:
Step Command Remarks
1. Enter system view. system-view N/A
2. Enter EVI tunnel interface
view.
interface tunnel number
[ mode evi ] N/A
3. Specify extended VLANs. evi extend-vlan vlan-list
By default, no VLANs are specified as
extended VLANs on any EVI tunnel.
To specify more extended VLANs, repeat
this step.
Configuring ENDP
ENDP enables the edge devices in an EVI network to discovery each other.
Configure an edge device as an ENDS to provide registration services or as an ENDC to register with an
ENDS.
Configuration guidelines
•For redundancy, you can configure up to two ENDSs on an EVI tunnel interface. These two ENDSs
work independently. The failure of one ENDS does not affect the neighbor discovery and EVI link
maintenance in the EVI network.
•When you enable ENDS on an EVI tunnel interface, an ENDC is automatically enabled. This ENDC
uses the source address of the EVI tunnel as the ENDS address. As a result, you can use the evi
neighbor-discovery client enable command to add only one ENDS address on an ENDS-enabled
EVI tunnel interface.
•To guarantee that each edge device can obtain the addresses of all its EVI neighbors, make sure the
ENDSs are the same across the EVI network.
•To improve security, enable ENDP authentication.
{Make sure all authentication-enabled ENDCs and ENDSs in an EVI network use the same
authentication key.
{If authentication is disabled on an ENDS, all ENDCs, including authentication-enabled ENDCs,
can register with the ENDS without authentication.
{If authentication is enabled on an ENDS, only authentication-enabled ENDCs that use the same
authentication key as the ENDS can register with the ENDS.
Configuring the edge device as an ENDS on the EVI tunnel
Step Command Remarks
1. Enter system view. system-view N/A
2. Enter EVI tunnel
interface view.
interface tunnel number [ mode
evi ] N/A

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Step Command Remarks
3. Enable ENDS. evi neighbor-discovery server
enable
By default, ENDS is disabled.
On an ENDS-enabled tunnel interface, you
can use the evi neighbor-discovery client
enable command to add one more ENDS,
and use the evi neighbor-discovery client
register-interval command to modify the
ENDC registration interval.
4. (Optional.) Enable
ENDP authentication.
evi neighbor-discovery
authentication { cipher | simple }
password
By default, ENDP authentication is
disabled.
Configuring the edge device as an ENDC on the EVI tunnel
Step Command Remarks
1. Enter system view. system-view N/A
2. Enter EVI tunnel
interface view.
interface tunnel number [ mode
evi ] N/A
3. Configure the edge
device as the ENDC of
an ENDS.
evi neighbor-discovery client
enable server-ip
By default, ENDC is disabled.
If ENDS is enabled on the EVI tunnel
interface, you can use this command to
specify only one more ENDS.
If ENDS is disabled, you can repeat this
command to specify up to two ENDSs.
ENDS address is the tunnel source address
configured on an ENDS-enabled EVI tunnel
interface.
4. (Optional.) Enable
ENDP authentication.
evi neighbor-discovery
authentication { cipher | simple }
password
By default, ENDP authentication is
disabled.
All ENDSs and ENDCs in an EVI network
must use the same authentication key.
5. Configure the interval
at which the ENDC
updates its registration
with ENDSs.
evi neighbor-discovery client
register-interval time-value
By default, an ENDC update its registration
with an ENDS every 15 seconds.
Enabling EVI on transport-facing physical interfaces
Enable EVI on all physical interfaces that provide transport network access for EVI tunnels. To avoid
forwarding failure, do not enable the spanning tree feature on these interfaces.
To enable EVI on an interface:
Step Command Remarks
1. Enter system view. system-view N/A

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Step Command Remarks
2. Enter Layer 2 or Layer 3
Ethernet interface view.
interface interface-type
interface-number N/A
3. Enable EVI on the interface. evi enable By default, EVI function is disabled
on all interfaces.
Tuning EVI IS-IS parameters
EVI IS-IS automatically runs on an EVI link immediately after the link is set up. You can tune EVI IS-IS
parameters to optimize the protocol performance.
EVI IS-IS configuration task list
All EVI IS-IS configuration tasks are optional.
Tasks at a glance Remarks
Creating an EVI IS-IS process N/A
Optimizing an EVI IS-IS network:
•Configuring the EVI IS-IS hello interval
•Configuring the hello multiplier for calculating the
adjacency hold time
•Configuring the DED priority
•Configuring the CSNP packet sending interval
•Configuring the minimum LSP sending interval and the
maximum number of LSPs sent at each interval
•Configuring the maximum LSP lifetime
•Configuring the LSP refresh interval
Perform the EVI IS-IS network optimization tasks
to enable fast EVI link failure detection, set
appropriate MAC reachability information
update interval, and control the volume of LSP
and CSNP traffic on an EVI network.
Specifying a routing policy for an EVI IS-IS process
Perform this task to advertise a subset of MAC
addresses instead of all local MAC addresses to
remote sites.
Enabling adjacency change logging N/A
Configuring SNMP notifications and context for EVI IS-IS N/A
Configuring Graceful Restart for an EVI IS-IS process Perform this task for providing nonstop services.
Increasing the maximum number of MAC entries in an LSP
for an EVI IS-IS process
Perform this task depending on the MAC
address table size on the edge device.
Creating an EVI IS-IS process
Each EVI network has one EVI IS-IS process. Before you can configure settings in EVI IS-IS process view,
you must create the process.
An EVI IS-IS process is created automatically when you perform any one of the following tasks on a tunnel
interface:

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•Specify extended VLANs.
•Perform network optimization tasks (see "Optimizing an EVI IS-IS network") except configuring the
EVI IS-IS hello interval and the maximum LSP lifetime.
The ID of an automatically created process is the same as the EVI tunnel interface number.
Alternatively, you can use the evi-isis command to create an EVI IS-IS process manually.
To delete a manually created EVI IS-IS process, you must use the undo evi-isis command.
•If EVI IS-IS settings exist on the EVI tunnel interface, the undo evi-isis command only deletes settings
configured in EVI IS-IS process view.
•If no EVI IS-IS settings exist on the EVI tunnel interface, the undo evi-isis command deletes both the
EVI IS-IS process and all settings configured in EVI IS-IS process view.
An automatically created EVI IS-IS process is automatically deleted when you delete all EVI IS-IS settings
from the EVI tunnel interface.
To create an EVI IS-IS process or enter its view:
Step Command Remarks
1. Enter system view. system-view N/A
2. Create an EVI IS-IS
process or enter EVI IS-IS
process view.
evi-isis process-id
By default, no EVI IS-IS process is configured.
The process ID you specify must be the same as
the EVI tunnel interface number.
The EVI IS-IS process takes effect after you
configure extended VLANs on the tunnel
interface.
Optimizing an EVI IS-IS network
Perform the tasks in this section to optimize an EVI IS-IS network for bandwidth efficiency and high
performance.
Configuring the EVI IS-IS hello interval
EVI edge devices send EVI IS-IS hellos over EVI links to establish and maintain adjacencies and elect the
inter-site DED on each EVI link.
A short interval increases the speed of network convergence but requires more system resources.
NOTE:
The hello interval of a DED is one-third of the hello interval set with the evi isis timer hello command.
To configure the EVI IS-IS hello interval on an EVI tunnel interface:
Step Command Remarks
1. Enter system view. system-view N/A
2. Enter EVI tunnel interface
view.
interface tunnel number [ mode
evi ] N/A

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Step Command Remarks
3. Configure the EVI IS-IS
hello interval. evi isis timer hello seconds
The default hello interval is 10 seconds.
If the edge device is a DED, its hello
interval is one-third of the hello interval set
with this command.
Configuring the hello multiplier for calculating the adjacency hold time
Adjacency hold time sets how long one edge device can retain the adjacency with another edge device.
It determines how long it takes for an edge device to detect a failed EVI link.
If the Graceful Restart function is disabled, the adjacency hold time equals the EVI IS-IS hello interval
multiplied by the hello multiplier set in this section.
If Graceful Restart is enabled, the adjacency hold time equals the restart interval or the EVI IS-IS hello
interval multiplied by the hello multiplier, whichever is greater.
An edge device sends its adjacency hold time in hello packets to update the adjacencies with its
neighbor edge devices. A neighbor edge device removes the adjacency with the advertising edge
device and recalculates routes if it does not receive an EVI IS-IS hello packet from the advertising edge
device before the time value expires.
To configure the multiplier for calculating the adjacency hold time on an EVI tunnel interface:
Step Command Remarks
1. Enter system view. system-view N/A
2. Enter EVI tunnel interface
view.
interface tunnel number [ mode
evi ] N/A
3. Configure the multiplier for
calculating the adjacency
hold time.
evi isis timer holding-multiplier
value
The default multiplier is 3.
The maximum adjacency hold time is
65535 seconds. If this value is exceeded,
the actual adjacency hold time is set to
65535 seconds.
Configuring the DED priority
The edge devices on an EVI link exchange their DED priority in EVI IS-IS hello packets to elect the inter-site
DED for periodic LSDB synchronization. You can use the evi isis timer csnp command to change the
synchronization interval.
The edge device with higher DED priority is more likely to be elected as an inter-site DED. If two edge
devices have the same DED priority, the device with the highest MAC address is elected.
To configure the DED priority of the edge device on an EVI tunnel interface:
Step Command Remarks
1. Enter system view. system-view N/A
2. Enter EVI tunnel interface view. interface tunnel number
[ mode evi ] N/A
3. Configure the DED priority. evi isis ded-priority value The default DED priority is 64.