Juniper IGP - CONFIGURATION GUIDE V11.1.X, Руководство по настройке

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host1(config-subif)# ip router isis engineering
8.
(Optional) Access Privileged Exec mode, and verify the route tag assignment.
host1(config-subif)# exit
host1(config)# exit
host1# show isis database detail
isis tag
■
Use to set a route tag for the IP addresses on an IS-IS interface before the route
is propagated to other routers in an IS-IS domain.
■
Specify a numeric tag value in the range 1–4294967295.
■
To make use of the route tag to modify route attributes or redistribute routes,
you must reference the tag value in a route map.
■
Example
host1(config)# interface atm 3/0
host1(config-if)# isis tag 45
■
Use the no version to remove the route tag from the interface.
■
See isis tag
Configuring Point-to-Point-over-LAN Circuits
You can deploy IS-IS on broadcast and point-to-point circuits. IS-IS treats these circuits
differently in several ways, such as when establishing neighbor adjacencies or flooding
link-state information.
Broadcast circuits use designated routers and are represented as virtual nodes in the
network topology. They require periodic database synchronization. By default, IS-IS
treats the broadcast link as LAN media and tries to bring up the LAN adjacency even
when the interface is configured as unnumbered or only a single neighbor exists on
that link.
In contrast, point-to-point circuits have less overhead, because they do not use
designated routers, the link-state database has no representation of the pseudonode
or network LSA, and they do not require periodic database synchronization. However,
if more than two routers are connected on the LAN media, routing information in
the network is reduced.
Although broadcast circuits are intended to handle more than two devices, in some
circumstances you might connect only two routers over the physical or virtual LAN.
Even though only two routers are connected, IS-IS treats the circuit as a broadcast
circuit that has many more connected routers, with all the associated broadcast
overhead but without the benefits of reduced routing information and of optimized
flooding that result from having more than two routers on the LAN.
You can use the isis network point-to-point command to configure IS-IS to operate
using point-to-point connections on a broadcast circuit when only two routers are
Configuring IS-IS Interface-Specific Parameters
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Chapter 6: Configuring IS-IS