Adjusting Neighbor Parameters

Devices establish neighbor relationships by exchanging Hello messages. PIM neighbor parameters include the interval for sending Hello messages, timeout period of a neighbor relationship, whether to deny a Hello message carrying the Generation ID option, and policy for filtering neighbors.

Context

You can set the interval for sending Hello messages and timeout period of a neighbor relationship either globally or on an interface.

Global configuration: takes effect on all interfaces.
Interface-specific configuration: takes precedence over the global configuration. If an interface-specific configuration is not available, the interface uses the global configuration.

Procedure

Adjust neighbor parameters globally.
1. Run system-view
  The system view is displayed.
2. Run pim [ vpn-instance vpn-instance-name ]
  The PIM view is displayed.
3. Run timer hello interval
  The interval for sending Hello messages is set.
4. Run hello-option holdtime holdtimeValue
  The neighbor timeout period carried in PIM Hello packets to be sent by a router.
  
  The interval for a router to send Hello messages must be shorter than the timeout period of neighbor relationships.
5. Run commit
  The configuration is committed.
Adjust neighbor parameters for a specific interface.
1. Run system-view
  The system view is displayed.
2. Configure a basic numbered ACL or a naming ACL as needed.
  - Configure a basic numbered ACL.
    1. Run acl [ number ] basic-acl-number [ match-order { auto | config } ]
      A basic numbered ACL is created, and the basic numbered ACL view is displayed.
    2. Run rule [ rule-id ] [ name rule-name ] { deny | permit } source { source-ip-address { source-wildcard | 0 } | any }
      Rules are configured for the basic numbered ACL.
  - Configure a naming ACL.
    1. Run acl name acl-name basic [ match-order { auto | config } ]
      A naming ACL is created, and the naming ACL view is displayed.
    2. Run rule [ rule-id ] [ name rule-name ] { deny | permit } source { source-ip-address { source-wildcard | 0 } | any }
      Rules are configured for the naming ACL.
3. Run quit
  Return to the system view.
4. Run interface interface-type interface-number
  The PIM interface view is displayed.
5. Run pim timer hello interval
  The interval for the interface to send Hello messages is set.
6. Run pim hello-option holdtime helloHoldTime
  The neighbor timeout period carried in PIM Hello packets to be sent by a router.
  
  The interval for an interface to send Hello messages must be shorter than the timeout period of neighbor relationships.
7. Run pim require-genid
  The interface is configured to accept only Hello messages with Generation ID fields.
  
  After an interface on the router is enabled with PIM-SM, the router generates a random number as the Generation ID of the Hello message. If the status of the router changes, a new Generation ID is generated. If the router finds that the Hello messages received from PIM neighbors carry different Generation IDs, the router considers that the PIM neighbor status changes.
8. Run pim neighbor-policy { basic-acl-number | acl-name acl-name }
  A neighbor filtering policy is configured.
  
  The neighbor filtering policy defines the range of valid neighbor addresses. The router discards Hello messages received from the routers that are not in this address range.
  - If a peer matches an ACL and the action is permit, the local router sets up a neighbor relationship with this peer.
  - If a peer matches an ACL and the action is deny, the local router does not set up a neighbor relationship with this peer.
  - If a peer does not match any ACL rule, the local router does not set up a neighbor relationship with this peer.
  - If a specified ACL does not exist or does not contain rules, the local router does not set up neighbor relationships with any peers.
9. Run commit
  The configuration is committed.