Configuring IS-IS

This section provides a table of feature default values and a procedure for configuring a feature system.

The following table lists IS-IS default values.

IS-IS Parameters

Parameter	Description	Default Value
authentication mode	The IS-IS MD5 authentication mode that provides a cryptographic hash MD5 digest to each IS-IS PDU.	MD5
distance	The administrative distance for IS-IS routes.	115
graceful restart state	Specifies whether graceful restart is enabled or disabled on a router.	disabled
graceful restart help peer	A function on the graceful restarting router peer that specifies whether the peer will help in the graceful restarting process.	enabled
graceful restart adjacency interval	Specifies the length of time graceful restart waits for the adjacency to form.	10 seconds
graceful restart interval	Specifies the length of time a graceful restart is allowed to continue without completing before graceful restart is terminated.	65535 seconds
graceful restart sync interval	Specifies the length of time graceful restart will wait for the IS-IS database to synchronize.	60 seconds
ignore LSP errors	Specifies that IS-IS ignores link state packet checksum errors on the device.	disabled
LSP buffer size	Specifies the LSP buffer size, based upon the maximum size of LSPs originated by this IS-IS routing instance.	1492 bytes
LSP generation interval	The minimum interval between generation of LSPs.	1 second
maximum LSP lifetime	The maximum time an LSP can persist without being refreshed.	1200 seconds
maximum paths	The maximum number of parallel routes to be installed into the routing table for this device.	8
metric style	The TLV metric style for this IS-IS instance.	both (narrow and wide)
overload bit	When set, instructs this intermediate system to tell other intermediate systems not to use it as an intermediate hop in the SPF calculation.	not set
SPF interval	The minimum amount of time between Shortest Path First (SPF) processing for this IS-IS instance.	33 milli-seconds
CSNP interval	The interval between sending sequence number PDUs (CSNP) on the interface.	10 seconds
hello interval	The minimum amount of time between sending hello PDUs on the interface.	10 seconds
hello multiplier	The number of hello packets a neighbor must miss before the intermediate system declares the adjacency down for the interface.	3
LSP MTU	The maximum PDU size for PDUs on the interface.	1490 bytes
LSP throttle	The minimum interval between the transmission of Link-State-Packets on the interface.	30 milli-seconds
metric	The cost of using the interface.	10
priority	The priority used to determine which intermediate system on a LAN is the designated router.	64
retransmit interval	The minimum amount of time between the retransmission of the same LSP on an interface.	5 seconds

The following procedure describes feature configuration on the Extreme Networks S- K- and 7100-Series devices. All commands used to configure IS-IS are entered in the IS-IS configuration mode after enabling IS-IS using the router isis command.

Configuring Global IS-IS

Step	Task	Command(s)
1	In global configuration mode, enable IS-IS globally on the device and enter IS-IS intermediate system configuration mode.	router isis
2	Specify the Network Access Point address for this IS-IS instance in the format xx.xxxx.(...)xxxx.xxxx.xxxx.00.	net net
3	Optionally configure the IS-IS type for this IS-IS instance.	is-type {level-1 | level-1-2 | level-2}
4	Specify the IS-IS domain password for this device.	domain-password password
5	Specify the area password.	area-password password
6	Optionally specify an IS-IS authentication key chain for the device.	authentication key-chain keychain [level-1 | level-1-2 | level-2]
7	Optionally set the authentication mode.	authentication mode {md5 | text} [level-1 | level-1-2 | level-2]
8	Optionally configure IS-IS authentication only on sent IS-IS frames.	authentication send-only [level-1 | level-1-2 | level-2]
9	In IS-IS configuration mode, optionally modify the IS-IS administrative distance for this IS-IS intermediate system.	distance [isis {external | internal}] weight
10	Optionally configure a dynamic hostname.	hostname dynamic hostname
11	Optionally enable IS-IS to ignore link state packet checksum errors on the device.	ignore-lsp-errors
12	Optionally configure the LSP buffer size based upon the specified maximum size of the LSP‘s originated by the IS-IS routing instance.	lsp-buf-size size [level-1 | level-1-2 | level-2]
13	Optionally configure the minimum interval between the generation of LSPs on the device.	lsp-gen-interval interval [level-1 | level-1-2 | level-2]
14	Optionally configure the maximum time that LSPs persist without being refreshed.	max-lsp-lifetime lifetime
15	Optionally configure the maximum number of parallel routes to be installed into the routing table for this device.	maximum-paths num
16	Optionally configure the TLV metric style for this IS-IS instance.	metric-style {wide | both}
17	In IS-IS configuration mode, optionally configure the redistribution of routing protocols into IS-IS.	redistribute {bgp | connected | ospf process_id| rip | static | blackhole | isis level-2 into level-1 [distribute-list access-list]} [route-map name] [metric metric-value]
18	Optionally configure the intermediate system to signal other intermediate systems not to use this intermediate system as an intermediate hop in their SPF calculations.	set-overload-bit [level-1 | level-1-2 | level-2]
19	Optionally configure the minimum amount of time between Shortest Path First (SPF) processing on an IS-IS instance.	spf-interval interval
20	Optionally create an aggregate IS-IS address for summarization of routes.	summary-address ip-address/length
21	Optionally enable IS-IS graceful restart for this router.	graceful-restart enable
22	Optionally set the length of time graceful restart will allow for the forming of adjacencies.	graceful-restart restart-adj-interval interval
23	Optionally set the length of time graceful restart will attempt to complete a restart before terminating.	graceful-restart restart-interval interval
1.	Optionally specify the amount of time graceful restart will allow for the synchronization of the database.	graceful-restart restart-sync-interval {level-1 | level-1-2 | level-2} interval

The following table describes IS-IS Interface configuration on Extreme Networks S- K- and 7100-Series devices. All IS-IS interface configuration commands are entered in interface configuration mode. All IS-IS interface configuration is optional.

Configuring IS-IS on the Interface

Task	Command(s)
If IPv6 routing will take place on the interface, enable IPv6 IS-IS routing on the interface. IPv4 IS-IS routing is enabled globally.	ipv6 router isis
Configure an IS-IS authentication key chain on an interface	isis authentication key-chain keychain [level-1 | level-2]
Configure the IS-IS authentication mode on an interface.	isis authentication mode {md5 | text} [level-1 | level-2]
Configure IS-IS authentication only on sent IS-IS frames on an interface.	isis authentication send-only [level-1 | level-2]
Configure the IS-IS type on an interface	isis circuit-type {level-1 | level-1-2 | level-2}
Configure the IS-IS complete sequence number PDU (CSNP) interval for the interface.	isis csnp-interval seconds [level-1 | level-1-2 | level-2]
Configure the IS-IS Hello Protocol Data Units interval for the interface.	isis hello-interval {seconds | minimal} [level-1 | level-1-2 | level-2]
Configure the number of hello packets a neighbor must miss before the intermediate system declares the adjacency down for the interface.	isis hello-multiplier multiplier [level-1 | level-1-2 | level-2]
Configure IS-IS hello padding on an interface.	isis hello-padding
Configure the maximum PDU size for PDUs on the interface.	isis lsp-mtu size
Configure the minimum interval between the transmission of Link-State Packets (LSP)s.	isis lsp-throttle interval
Configure the cost of using the interface.	isis metric cost [level-1 | level-1-2 | level-2]
Configure a two device network that uses broadcast media and IS-IS to function as a point-to-point link.	isis network-point-to-point
Configure the suppression of IS-IS packets from being transmitted by the interface and received packets from being processed by the interface.	isis passive-interface
Configure an authentication password for the interface.	isis password password [level-1 | level-2]
Configure the priority used to determine which intermediate system on a LAN is the designated router.	isis priority priority [level-1 | level-1-2 | level-2]
Configure the minimum interval between retransmissions of the same LSP.	isis retransmit-interval interval

The following procedure describes IS-IS IPv6 unicast address family configuration on the Extreme Networks S- K- and 7100-Series devices.

Configuring IS-IS IPv6 Unicast Address Family

Step	Task	Command(s)
1	From global configuration mode, optionally enter the IPv6 unicast IS-IS address family configuration mode to configure administrative distance, redistribution of routing protocols into IS-IS, and address summarization for IPv6 unicast.	address-family ipv6 unicast
2	In IPv6 unicast address family configuration mode, optionally modify the IS-IS administrative distance for this IS-IS intermediate system.	distance [isis {external | internal}] weight
3	In IPv6 unicast address mode, optionally configure the redistribution of routing protocols into IS-IS.	redistribute {bgp | connected | ospf process_id| rip | static | blackhole | isis level-2 into level-1 [distribute-list access-list]} [route-map name] [metric metric-value]
4	In IPv6 unicast address family configuration mode, optionally create an aggregate IS-IS address for summarization of routes.	summary-address ip-address/length

The following table describes how to display IS-IS information on Extreme Networks S- K- and 7100-Series devices. All IS-IS display commands can be entered from any command mode.

Displaying IS-IS Information

Task	Command(s)
Display IS-IS database information for the intermediate system.	show isis database [lsp lsp] | [level-1] | [level-2] | [detail] | [verbose]
Display the hostname per LSP ID.	show isis hostname
Display the frequency and reason for LSP changes on an interface.	show isis lsp-log
Display IS-IS intermediate system neighbors.	show isis neighbors
Display the IS-IS topology.	show isis topology

Refer to the S-, K-, and 7100 Series CLI Reference Guide for more information about each command.