Displays information about IS-IS interfaces for a device.
Privileged EXEC mode
IS-IS is supported only on devices based on the DNX chipset family. For a list of such devices, see "Supported Hardware".
The show isis interface command displays the following information:
| Output field | Description | 
|---|---|
| Total number of IS-IS interfaces | The number of interfaces on which IS-IS is enabled. | 
| Interface | The interface number to which the information listed below applies. | 
| Circuit State | The state of the circuit, which can be one of the following: 
 | 
| Circuit Mode | The IS-IS type in use on the circuit. The mode can be one of the following: 
 | 
| Circuit Type | The type of IS-IS circuit running on the interface. The circuit type can be one of the following: 
 | 
| Passive State | The passive state determines whether the interface is allowed to form an IS-IS adjacency with the IS at the other end of the circuit. The state can be one of the following: 
 | 
| Circuit Number | The ID that the instance of IS-IS running on the interface applied to the circuit between this interface and the interface at the other end of the link. | 
| MTU | The maximum length supported for IS-IS PDUs sent on this interface. | 
| Level-1 Auth-mode | One of the following authentication modes set for Level-1 on the router: 
 | 
| Level-2 Auth-mode | One of the following authentication modes set for Level-2 on the router: 
 This parameter is not displayed for interfaces that are configured with a Point-to-Point circuit type. This is because separate Level-2 Hello messages are not sent on Point-to-Point interfaces. Consequently, "Hello Interval", "Hello Multiplier", and "Authentication" parameters should always be configured in the Level-1 mode for Point-to-Point interfaces. | 
| Level-1 Metric | The default-metric value that the device inserts in IS-IS Level-1 PDUs for this interface. | 
| Level-1 Priority | The priority of this IS to be elected as the Designated IS for Level-1 in this broadcast network. | 
| Level-1 Hello Interval | The number of seconds the software waits between sending Level-1 hello PDUs to the IS at the other end of the circuit. | 
| Level-1 Hello Multiplier | The number by which the software multiplies the hello interval to calculate the hold time set in Level-1 Hello PDUs sent on the circuit. | 
| Level-1 Designated IS | The NET of the Level-1 Designated IS. | 
| Level-1 DIS Changes | The number of times the NET of the Level-1 Designated IS has changed. | 
| Level-2 Metric | The default-metric value that the device inserts in IS-IS Level-2 PDUs for this interface. | 
| Level-2 Priority | The priority of this IS to be elected as the Designated IS for Level-2 in this broadcast network. | 
| Level-2 Hello Interval | The number of seconds the software waits between sending Level-2 Hello messages to the IS at the other end of the circuit. | 
| Level-2 Hello Multiplier | The number by which the software multiplies the hello interval to calculate the hold time set for Level-2 Hello PDUs sent on this circuit. This parameter is not displayed for interfaces that are configured with a Point-to-Point circuit type. This is because separate Level-2 Hello messages are not sent on Point-to-Point interfaces. Consequently, "Hello Interval", "Hello Multiplier", and "Authentication" parameters should always be configured in the Level-1 mode for Point-to-Point interfaces. | 
| Level-2 Designated IS | The NET of the Level-2 Designated IS. | 
| Level-2 DIS Changes | The number of times the NET of the Level-2 Designated IS has changed. | 
| Next IS-IS LAN Level-1 Hello | Number of seconds before next Level-1 Hello PDU will be transmitted by the device. | 
| Next IS-IS LAN Level-2 Hello | Number of seconds before next Level-2 Hello PDU will be transmitted by the device. | 
| Number of active Level-1 adjacencies | The number of ISs with which this interface has an active Level-1 adjacency. | 
| Number of active Level-2 adjacencies | The number of ISs with which this interface has an active Level-2 adjacency. | 
| Circuit State Changes | The number of times the state of the circuit has changed. | 
| Circuit State Adjacencies Changes | The number of times an adjacency has started or ended on this circuit. | 
| Rejected Adjacencies | The number of adjacency attempts by other ISs rejected by the device. | 
| Circuit Authentication L1 failures | The number of times the device rejected a circuit because the authentication did not match the authentication configured for Level 1 on the device. | 
| Circuit Authentication L2 failures | The number of times the device rejected a circuit because the authentication did not match the authentication configured for Level 2 on the device. This parameter is not displayed for interfaces that are configured with a Point-to-Point circuit type. This is because separate Level-2 Hello messages are not sent on Point-to-Point interfaces. Consequently, "Hello Interval", "Hello Multiplier", and "Authentication" parameters should always be configured in the Level-1 mode for Point-to-Point interfaces. | 
| Bad LSP | The number of times the interface received a bad LSP from an IS at the other end of the circuit. The following conditions can cause an LSP to be bad: 
 | 
| Control Messages Sent | The number of IS-IS control PDUs sent on this interface. | 
| Control Messages Received | The number of IS-IS control PDUs received on this interface. | 
| Hello Padding: | The Hello Padding configuration, which can be: 
 | 
| IP Enabled | If set to TRUE, the IP protocol is enabled for this circuit. | 
| IP Address and Subnet Mask | The IP address and subnet mask for this interface. | 
| IPv6 Enabled | If set to TRUE, the IPv6 protocol is enabled for this circuit. | 
| IPv6 Address and Subnet Mask | The IPv6 address and subnet mask for this interface. | 
| Ipv6 Link-Local Addresses | The IPv6 link local address for this interface. | 
| MPLS TE Enabled: | If set to TRUE, MPLS Traffic Engineering protocol is enabled for this circuit. | 
| BFD Enabled: | If set to TRUE, BiDirectional Forwarding Detection is enabled for this circuit. | 
The following example displays information about IS-IS interfaces for a device.
device# show isis interface
Total number of IS-IS Interfaces: 11
Interface: Ve 301
   Circuit State: UP Circuit Mode: Level 1-2
   Circuit Type: BCAST Passive State: FALSE
   Circuit Number: 2, MTU: 1500
   Level-1 Auth-mode: NONE
   Level-2 Auth-mode: NONE
   Level-1 Metric: 10, Level-1 Priority: 64
   Level-1 Hello Interval: 10, Level-1 Hello Multiplier: 3
   Level-1 Designated IS: R1-02 Level-1 DIS Changes: 2
   Level-2 Metric: 10, Level-2 Priority: 64
   Level-2 Hello Interval: 10, Level-2 Hello Multiplier: 3
   Level-2 Designated IS: R1-02 Level-2 DIS Changes: 2
   Next IS-IS LAN Level-2 Hello in 11 seconds
   Number of active Level-2 adjacencies: 0
   Next IS-IS LAN Level-1 Hello in 1 seconds
   Number of active Level-1 adjacencies: 0
   Circuit State Changes: 1 Circuit Adjacencies State Changes: 0
   Rejected Adjacencies: 0
   Circuit Authentication L1 failures: 0
   Circuit Authentication L2 failures: 0
   Bad LSPs: 0
   Control Messages Sent: 7577 Control Messages Received: 0
   Hello Padding: Enabled
   IP Enabled: TRUE
   IP Addresses:
     11.2.1.1/30
   IPv6 Enabled: FALSE
   MPLS TE Enabled: FALSE
   BFD Enabled: FALSE
   LDP-SYNC: Disabled, State:
Interface: Ve 302
   Circuit State: UP Circuit Mode: Level 1-2
   Circuit Type: BCAST Passive State: FALSE
   Circuit Number: 3, MTU: 1500
   Level-1 Auth-mode: NONE
   Level-2 Auth-mode: NONE
   Level-1 Metric: 10, Level-1 Priority: 64
   Level-1 Hello Interval: 10, Level-1 Hello Multiplier: 3
   Level-1 Designated IS: R1-03 Level-1 DIS Changes: 2
   Level-2 Metric: 10, Level-2 Priority: 64
   Level-2 Hello Interval: 10, Level-2 Hello Multiplier: 3
   Level-2 Designated IS: R1-03 Level-2 DIS Changes: 2
   Next IS-IS LAN Level-2 Hello in 2 seconds
   Number of active Level-2 adjacencies: 0
   Next IS-IS LAN Level-1 Hello in 4 seconds
   Number of active Level-1 adjacencies: 0
   Circuit State Changes: 1 Circuit Adjacencies State Changes: 0
   Rejected Adjacencies: 0
   Circuit Authentication L1 failures: 0
   Circuit Authentication L2 failures: 0
   Bad LSPs: 0
   Control Messages Sent: 7600 Control Messages Received: 0
   Hello Padding: Enabled
   IP Enabled: TRUE
   IP Addresses:
     11.2.1.5/30
   IPv6 Enabled: FALSE
   MPLS TE Enabled: FALSE
   BFD Enabled: FALSE
   LDP-SYNC: Disabled, State:
…
 
	 
	  
		The following example displays summarized information about IS-IS interfaces for a device.
device# show isis interface brief Total number of IS-IS Interfaces: 11 Interface Type State Mode Passive MTU UpAdj DIS StateChg AdjStateChg Ve 301 BCAST UP L12 FALSE 1500 0 None 1 0 Ve 302 BCAST UP L12 FALSE 1500 0 None 1 0 Ve 303 BCAST UP L12 FALSE 1500 0 None 1 0 Ve 304 BCAST UP L12 FALSE 1500 0 None 1 0 Ve 305 BCAST UP L12 FALSE 1500 0 None 1 0 Ve 306 BCAST UP L12 FALSE 1500 0 None 1 0 Ve 307 BCAST UP L12 FALSE 1500 0 None 1 0 Ve 308 BCAST UP L12 FALSE 1500 0 None 1 0 Ve 309 BCAST UP L12 FALSE 1500 0 None 1 0 Ve 310 BCAST UP L12 FALSE 1500 0 None 1 0 Lo 1 BCAST UP L12 TRUE 0 0 None 1 0