hello (MPLS RSVP)

Enables RSVP Hello on all RSVP interfaces and configure the interval and tolerance.

Syntax

hello [ interval seconds ] [tolerance number]

no hello [ interval ] [tolerance ]

Command Default

RSVP Hello is disabled on the device.

The default interval is 9 seconds.

The default tolerance is 3 unacknowledged RSVP Hello requests before timeout.

Parameters

interval seconds: Specifies the interval in seconds between two RSVP Hello requests. Enter an integer from 1 to 60.
tolerance number: Specifies the number of unacknowledged RSVP Hello requests before timeout. Enter a number from 1 to 255.

Modes

MPLS RSVP configuration mode

MPLS interface RSVP configuration mode

Usage Guidelines

When you configure the interval and tolerance for the RSVP-TE Hello protocol globally, they are pushed to all MPLS interfaces when MPLS interface configurations are not present. In addition to these two parameters, you can configure the acknowledgments globally.

You can configure RSVP-TE Hello interval and tolerance on an MPLS interface. The interface configurations take precedence over global configurations.

By default, acknowledgments are not sent on the MPLS interface supporting RSVP Hello when no sessions are taken on the interface.

Caution

When disabling RSVP hello, disable it on both sides of the link at the same time to avoid bringing down all the RSVP sessions going over that link.

Use the no command to disable RSVP Hello, or to reset the default interval or tolerance settings.

The no hello command on the MPLS interface sets the RSVP-TE Hello parameters to the globally configured RSVP Hello parameter values. If RSVP Hello is not configured globally, it disables the RSVP Hello on the MPLS interface. Executing this removes the configuration from the interface.

MPLS is supported only on devices based on the DNX chipset family. For a list of such devices, see "Supported Hardware".

Examples

The following example enables RSVP hello globally and configures the interval at 15 seconds and a tolerance of 8.

device# configure terminal
device(config)# router mpls
device(config-router-mpls)# rsvp
device(config-router-mpls-rsvp)# hello interval 15 tolerance 8

The following example enables RSVP hello on an MPLS interface and configures the interval at 20 seconds and a tolerance of 10.

device(config)# router mpls
device(config-router-mpls)# mpls-interface ethernet 0/12
device(config-router-mpls-interface-0/12)# rsvp
device(config-router-mpls-interface-0/12-rsvp)# hello interval 20 tolerance 10