peer-ip ttl
Function
The peer-ip ttl command sets the TTL of the BFD packet.
The undo peer-ip ttl command restores the default TTL of the BFD packet.
Format
peer-ip peer-ip mask-length ttl { single-hop | multi-hop } ttl-value
undo peer-ip peer-ip mask-length ttl { single-hop | multi-hop }
Parameters
| Parameter | Description | Value |
|---|---|---|
| peer-ip | Specifies the IP segment address. peer-ip and mask-length are used together to specify a range of IP addresses. | - |
| mask-length | Specifies the length of the IP address mask. | The value ranges from 8 to 32. |
| single-hop | Indicates the single-hop BFD session. | - |
| multi-hop | Indicates the multi-hop BFD session. | - |
| ttl-value | Specifies the value of the TTL. | The value ranges from 1 to 255. |
Usage Guidelines
The default TTL of the BFD packet varies with the BFD session type. In static BFD sessions, the TTL of the single-hop BFD packet is 255 and the TTL of the multi-hop BFD packet is 254. In dynamic BFD sessions, the TTL of the single-hop BFD packet is 255; the TTL of the multi-hop BFD packet is 253.
- Static configuration of the BFD session: The parameters of the BFD session, such as the local discriminator and the remote discriminator, are configured manually through command lines. Then, the request of BFD session establishment is manually delivered.
- Dynamic establishment of the BFD session: When a peer relationship is set up according to a routing protocol, BFD is notified of the peer information and the detection parameters. Then, a BFD session is created according to the received parameters.
You can use this command to set the TTL globally to enable Huawei devices running different FW versions to interwork with each other and non-Huawei devices.
The length of the IP segment address must match the mask. The configuration of the long mask is predominant over the configuration of the short mask.
For BFD sessions of different types, all of their IP segment addresses, masks, and TTL values cannot be the same.
When the IP segment addresses and the masks are the same, the TTL value of the single-hop BFD session must be greater than the TTL value of the multi-hop BFD session.
When a great number of multi-hop BFD sessions are set up, it may take a long time to update the destination ports. Therefore, if the interval for configuring multi-hop BFD sessions is set to a small value, the system prompts that the BFD session is being updated and you may try later.