Verifying IS-IS on a Services Router

To verify IS-IS, perform these tasks:

Purpose

Verify the status of IS-IS-enabled interfaces.

Action

From the CLI, enter the show isis interface brief command.

IS-IS interface database:
Interface  L CirID Level 1	DR	Level 2 DR		
lo0.0      3  0x1  router1		router.01			
ge-0/0/1.0 2  0x9  Disabled		router.03
ge-1/0/0.0 2	0x7  Disabled		router.05

What it Means

Verify that the output shows the intended configuration of the interfaces on which IS-IS is enabled.

See Also

Purpose

Verify the details of IS-IS-enabled interfaces.

Action

From the CLI, enter the show isis interface detail command.

lo0.0
			Index:3, State:0x7, Circuit id: 0x1, Circuit type:3
			LSP interval: 100 ms, Sysid: router1
			Level Adjacencies Priority Metric Hello(s) Hold(s)
			    1           0       64      0       9    27
       2           0       64      0       9    27
		ge-0/0/1.0
       Index:3, State:0x106, Circuit id: 0x9, Circuit type:2
			LSP interval: 100 ms, Sysid: router1
			Level Adjacencies Priority Metric Hello(s) Hold(s)
			    1           0       64      0       9    27
       2           0       64      0       9    27

What it Means

Check the following output fields and verify that the output shows the intended configuration of IS-IS-enabled interfaces:

• Interface—Interface configured for IS-IS
• State—Internal implementation information
• Circuit id—Circuit identifier
• Circuit type—Configured level of IS-IS:
  • 1—Level 1 only
  • 2—Level 2 only
  • 3—Level 1 and Level 2
• LSP interval—Time between IS-IS information messages
• Sysid—System identifier
• L or Level—Type of adjacency:
  • 1—Level 1 only
  • 2—Level 2 only
  • 3—Level 1 and Level 2
• Adjacencies—Adjacencies established on the interface
• Priority—Priority value established on the interface
• Metric—Metric value for the interface
• Hello(s)—Intervals between hello PDUs
• Hold(s)—Hold time on the interface

See Also

Purpose

Display brief information about IS-IS neighbors.

Action

From the CLI, enter the show isis adjacency brief command.

IS-IS adjacency database:
		 Interface		System				L  State				Hold (secs) SNPA
		 ge-0/0/0.0		1921.6800.5067		2  Up								13
		 ge-0/0/1.0		1921.6800.5067		2	Up								25
		 ge-0/0/2.0		1921.6800.5067		2  Up								19

What it Means

Verify adjacent routers in the IS-IS database.

See Also

Purpose

Display extensive information about IS-IS neighbors.

Action

From the CLI, enter the show isis adjacency extensive command.

R1
  Interface: so-0/0/0.0, Level: 2, State: Up, Expires in 25 secs
  Priority: 0, Up/Down transitions: 1, Last transition: 4w6d 19:38:52 ago
  Circuit type: 2, Speaks: IP, IPv6
  Topologies: Unicast
  Restart capable: Yes
  IP addresses: 10.1.12.1
  Transition log:
  When                  State        Reason
  Wed Jul 13 16:26:11   Up           Seenself

R3
  Interface: so-0/0/1.0, Level: 2, State: Up, Expires in 23 secs
  Priority: 0, Up/Down transitions: 1, Last transition: 6w5d 19:07:16 ago
  Circuit type: 2, Speaks: IP, IPv6
  Topologies: Unicast
  Restart capable: Yes
  IP addresses: 10.1.23.2
  Transition log:
  When                  State        Reason
  Thu Jun 30 16:57:46   Up           Seenself

R6
  Interface: so-0/0/2.0, Level: 2, State: Up, Expires in 25 secs
  Priority: 0, Up/Down transitions: 1, Last transition: 6w0d 18:01:18 ago
  Circuit type: 2, Speaks: IP, IPv6
  Topologies: Unicast
  Restart capable: Yes
  IP addresses: 10.1.26.2
  Transition log:
  When                  State        Reason
  Tue Jul  5 18:03:45   Up           Seenself 

What it Means

Check the following fields and verify adjacency information about IS-IS neighbors:

• Interface—Interface through which the neighbor is reachable
• L or Level—Configured level of IS-IS:
  • 1—Level 1 only
  • 2—Level 2 only
  • 3—Level 1 and Level 2

  An exclamation point before the level number indicates that the adjacency is missing an IP address.

• State—Status of the adjacency: Up, Down, New, One-way, Initializing, or Rejected
• Event—Message that identifies the cause of a state
• Down reason—Reason the adjacency is down
• Restart capable—Denotes a neighbor configured for graceful restart
• Transition log—List of transitions including When, State, and Reason

See Also