c-bsr holdtime

Function

The c-bsr holdtime command sets a timeout period during which candidate-bootstrap routers (C-BSRs) wait to receive bootstrap messages from the BSR.

The undo c-bsr holdtime command restores the default setting.

By default, the timeout period is 130 seconds.

Format

c-bsr holdtime holdtimeValue

undo c-bsr holdtime

Parameters

Parameter	Description	Value
holdtimeValue	Specifies a timeout period during which C-BSRs wait to receive bootstrap messages from the BSR.	The value is an integer ranging from 1 to 214748364, in seconds.

Parameter

Description

Value

holdtimeValue

Specifies a timeout period during which C-BSRs wait to receive bootstrap messages from the BSR.

The value is an integer ranging from 1 to 214748364, in seconds.

Views

IPv6 PIM view, VPN instance IPv6 PIM view

Default Level

2: Configuration level

Task Name and Operations

Task Name	Operations
pim	write

Usage Guidelines

Usage Scenario

To maintain the bootstrap router (BSR) status, a BSR dynamically elected among C-BSRs needs to send bootstrap messages carrying the BSR IP address and the rendezvous point (RP)-set information to the C-BSRs at a specific interval (called BS_interval) that can be set using the c-bsr interval command.

Only the BSR sends bootstrap messages, and each C-BSR starts a timer and waits to receive bootstrap messages from the BSR before the timer times out. To set the timeout period (called holdtime) of the timer, run the c-bsr holdtime command.

If a C-BSR receives a bootstrap message from the BSR, the C-BSR resets the timer.
If a C-BSR does not receive a bootstrap message after the holdtime times out, the C-BSR considers the BSR faulty and triggers a new round of BSR election to prevent service interruptions.

Prerequisites

The multicast routing function has been enabled using the multicast ipv6 routing-enable command in the public network instance view.

Configuration Impact

If the c-bsr holdtime command is run more than once, the latest configuration overrides the previous one.

Precautions

You must set the same BS_interval and the same holdtime on all C-BSRs in the same PIM domain. Otherwise, a BSR may be frequently elected. Note the following points:

If both BS_interval and holdtime are set, ensure that BS_interval is smaller than holdtime.
If only BS_interval or Holdtime is set, calculate the other one using the formula: Holdtime = 2 x BS_interval + 10.
If the holdtime is configured and the calculated BS_interval is smaller than the minimum value of BS_interval, the minimum value of BS_interval is used.
If the BS_interval is configured and the calculated holdtime is greater than the maximum value of holdtime, the maximum value of holdtime is used.
The default BS_interval is 60 seconds, and the default holdtime is 130 seconds.

Example

# In the public network instance, specify 150 seconds as the timeout period during which C-BSRs wait to receive bootstrap messages from the BSR.

<HUAWEI> system-view
[~HUAWEI] multicast ipv6 routing-enable
[*HUAWEI] pim-ipv6
[*HUAWEI-pim6] c-bsr holdtime 150