The isis circuit-type command simulates the network type of an IS-IS broadcast interface to a P2P interface.
The undo isis circuit-type command restores the default network type of an IS-IS interface.
By default, the network type of an interface is determined by the physical type of the interface.
| Parameter | Description | Value |
|---|---|---|
| p2p | Sets the network type of an IS-IS interface to P2P. | - |
| strict-snpa-check | Enables IS-IS to check the SNPA address of each received LSP or SNP. | - |
Usage Scenario
The network type of IS-IS interfaces at the ends of the link must be identical. Otherwise, the two interfaces cannot set up the neighbor relationship. In most cases, the network types of interfaces on a broadcast network and a P2P network are Ethernet and P2P respectively.
The isis circuit-type command sets the network type of an interface to simulate a P2P interface so that the network type of IS-IS interfaces at the ends of the link is identical and the neighbor relationship can be established between them.
When an IS-IS neighbor relationship is established between a P2P interface and a simulated P2P interface and the simulated P2P interface has direct neighbors, the P2P interface may receive unneeded packets from these direct neighbors. To prevent the P2P interface from accepting these unneeded packets, specify strict-snpa-check in the isis circuit-type command to enable IS-IS to check the SNPA address of each received LSP or SNP. After the command is run, the P2P interface accepts only the packets whose SNPA addresses are included in the local neighbor address list, which improves network security.
Precautions
After a broadcast interface is simulated as a P2P interface using the isis circuit-type command, the interval for sending Hello packets, the number of Hello packets that IS-IS does not receive from a neighbor before the neighbor is declared Down, interval for resending LSP packets on a P2P link, and various IS-IS authentication modes are restored to the default settings; other configurations such as the DIS priority, DIS name, and interval for sending CSNP packets on a broadcast network become invalid.
After the undo isis circuit-type command is run to restore the network type of an IS-IS interface, the interval for sending Hello packets, the number of Hello packets that IS-IS does not receive from a neighbor before the neighbor is declared Down, interval for resending LSP packets on a P2P link, various IS-IS authentication modes, DIS priority, and interval for sending CSNP packets on a broadcast network are restored to the default settings.
# Set the network type of VLANIF100 to P2P.
<HUAWEI> system-view [HUAWEI] isis [HUAWEI-isis-1] network-entity 01.0000.0000.0001.00 [HUAWEI-isis-1] quit [HUAWEI] interface vlanif 100 [HUAWEI-Vlanif100] isis enable 1 [HUAWEI-Vlanif100] isis circuit-type p2p
# Set the network type of GE0/0/1 to P2P.
<HUAWEI> system-view [HUAWEI] isis [HUAWEI-isis-1] network-entity 01.0000.0000.0001.00 [HUAWEI-isis-1] quit [HUAWEI] interface gigabitethernet 0/0/1 [HUAWEI-GigabitEthernet0/0/1] undo portswitch [HUAWEI-GigabitEthernet0/0/1] isis enable 1 [HUAWEI-GigabitEthernet0/0/1] isis circuit-type p2p