Configuring Passive Interfaces - Juniper IGP - CONFIGURATION GUIDE V11.1.X Configuration Manual

JUNOSe 11.0.x IP, IPv6, and IGP Configuration Guide
isis priority

Configuring Passive Interfaces

You can configure an IS-IS passive interface. A passive interface only advertises its
IP address in its LSPs; it does not send or receive IS-IS packets.
Optionally, you can set a route tag for an IS-IS passive interface by including the tag
keyword and a numeric tag value in the passive-interface command.
Passive interfaces have a metric of zero by default. You can set a different metric
for a particular passive interface by specifying the value along with the metric
keyword. A global default metric set with the metric command does not affect any
passive interface. Similarly, configuring a reference bandwidth for IS-IS has no effect
on passive interfaces. Metrics specified for a passive interface apply to both level 1
and level 2 interfaces unless you restrict the metric to a single level.
passive-interface
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Configuring IS-IS Interface-Specific Parameters
Use to set the priority of use for your designated router.
You can configure an individual priority for level 1 and level 2 by choosing a
priority level in the range 0–127.
The default priority level is 64.
Specifying the level 1 or level 2 keyword resets the priority only for level 1 or
level 2 routing, respectively.
Priorities are used to determine which router in the network is the designated
intermediate system (DIS); the router with the highest priority becomes the DIS.
Priorities are advertised in hellos.
IS-IS has no backup designated router. Setting the priority to 0 reduces the chance
of this router becoming the DIS, but does not prevent it. If a router with a higher
priority is identified, it takes over the role from the current DIS. When priorities
are equal, the highest MAC address breaks the tie and becomes the DIS.
Example
host1(config-if)#isis priority 80 level-1
Use the no version to restore the default value, 64.
See isis priority
Use to configure an IS-IS interface so that its IP address is advertised in its
link-state PDUs but no IS-IS packets are sent from or received on the interface.
Use the optional tag keyword to specify a tag value for an IS-IS passive interface
before the route is propagated to other routers in an IS-IS domain. The tag value
must be a number in the range 1–4294967295.
Use the optional metric keyword to specify a metric value for an IS-IS passive
interface. The metric value must be a number in the range 1–16777215. This
value overrides the default metric of zero.