Related Documentation
- ACX, J, M, MX, SRX, T Series
- Example: Configuring IS-IS
- ACX, EX, M, MX, PTX, SRX, T Series, QFabric System, QFX Series standalone switches
- hello-interval
- EX, M, PTX, T Series, QFX Series standalone switches
- Configuring Graceful Routing Engine Switchover
- EX, M, PTX, QFX, T Series
- Example: Configuring IS-IS for GRES with Graceful Restart
hold-time (Protocols IS-IS)
Syntax
Hierarchy Level
Release Information
Statement introduced before Junos OS Release 7.4.
Statement introduced in Junos OS Release 9.0 for EX Series switches.
Statement introduced in Junos OS Release 12.1 for the QFX Series.
Description
Set the length of time a neighbor considers this router to be operative (up) after receiving a hello packet. If the neighbor does not receive another hello packet within the specified time, it marks this routing device as inoperative (down). The hold time itself is advertised in the hello packets.
The hold time specifies how long a neighbor should consider this routing device to be operative without receiving another hello packet. If the neighbor does not receive a hello packet from this routing device within the hold time, it marks the routing device as being unavailable.
For systems configured with graceful routing switchover (GRES) with Graceful Restart, the hold time for Master and Backup Routing Engines should be set to a value higher than 40 seconds. This ensures that adjacencies between the Routing Engine and the neighboring peer 'helper' routers do not time out, stopping graceful restart, and all traffic.
Options
seconds—Hold-time value, in seconds.
Range: 3 through 65,535 seconds, or 1 to send out hello packets every 333 milliseconds
Default: 9 seconds (for designated intermediate system [DIS] routers), 27 seconds (for non-DIS routers; three times the default hello interval)
Required Privilege Level
routing—To view this statement in the configuration.
routing-control—To add this statement to the configuration.
Related Documentation
- ACX, J, M, MX, SRX, T Series
- Example: Configuring IS-IS
- ACX, EX, M, MX, PTX, SRX, T Series, QFabric System, QFX Series standalone switches
- hello-interval
- EX, M, PTX, T Series, QFX Series standalone switches
- Configuring Graceful Routing Engine Switchover
- EX, M, PTX, QFX, T Series
- Example: Configuring IS-IS for GRES with Graceful Restart
Published: 2014-07-25
Related Documentation
- ACX, J, M, MX, SRX, T Series
- Example: Configuring IS-IS
- ACX, EX, M, MX, PTX, SRX, T Series, QFabric System, QFX Series standalone switches
- hello-interval
- EX, M, PTX, T Series, QFX Series standalone switches
- Configuring Graceful Routing Engine Switchover
- EX, M, PTX, QFX, T Series
- Example: Configuring IS-IS for GRES with Graceful Restart
