Configuring a DR priority

Configuring a DR priority

The DR priority option lets you give preference to a particular device in the DR election process by assigning it a numerically higher DR priority. This value can be set for IPv4 interfaces. To set a DR priority higher than the default value of 1, use the ip pim dr-prioritycommand as shown:

device(config-if-e10000-3/24)# ip pim dr-priority 50

Syntax: [no] ip pim dr-priority priority-value

The priority-valuevariable is the value that you want to set for the DR priority. Optional values are: 0 - 65535. The default value is 1.

The no option removes the command and sets the DR priority back to the default value of 1.

The following information may be useful for troubleshooting.

1.If more than one device has the same DR priority on a subnet (as in the case of default DR priority on all), the device with the numerically highest IP address on that subnet is elected as the DR.

2.The DR priority information is used in the DR election ONLY IF ALL the PIM devices connected to the subnet support the DR priority option. If there is at least one PIM device on the subnet that does not support this option, then the DR election falls back to the backwards compatibility mode in which the device with the numerically highest IP address on the subnet is declared the DR regardless of the DR priority values.

Displaying basic PIM Dense configuration information

To display PIM Dense configuration information, enter the following command at any CLI level.

Device(config)# show ip pim dense

 

 

Global PIM Dense Mode Settings

12992

Current Count

: 2

Maximum Mcache

:

Hello interval

:

30

Neighbor timeout

: 105

Join/Prune interval

:

60

Inactivity interval

: 180

Hardware Drop Enabled

:

Yes

Prune Wait Interval

: 3

Graft Retransmit interval :

180

Prune Age

: 180

Route Precedence

:

mc-non-default mc-default uc-non-default uc-default

Syntax: show ip pim [ vrf vrf-name] dense

The vrf keyword allows you to display PIM dense configuration information for the VRF instance identified by the vrf-namevariable.

This display shows the following information.

Field

Description

 

 

Maximum Mcache

The maximum number multicast cache entries allowed on the device.

 

 

Current Count

The number of multicast cache entries currently used.

 

 

Hello interval

How frequently the device sends hello messages out the PIM dense interfaces.

 

 

Neighbor timeout

The interval after which a PIM device will consider a neighbor to be absent.

 

 

Join/Prune interval

How long a PIM device will maintain a prune state for a forwarding entry.

 

 

FastIron Ethernet Switch IP Multicast Configuration Guide

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Brocade Communications Systems IPMC5000PEF Configuring a DR priority, Displaying basic PIM Dense configuration information