Alcatel-Lucent 7750 SR-OS, Руководство по настройке

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Router Interface Commands
Page 182 7750 SR OS Router Configuration Guide
The implementation already allows the user to exclude an interface in IS-IS or OSPF, an OSPF area,
or an IS-IS level from the LFA SPF.
If a prefix is excluded from LFA, then it will not be included in LFA calculation regardless of its
priority. The prefix tag will, however, be used in the main SPF. Note that prefix tags are defined for
the IS-IS protocol but not for the OSPF protocol.
The default action of the loopfree-alternate-exclude command, when not explicitly specified by the
user in the prefix policy, is a “reject”. Thus, regardless if the user did or did not explicitly add the
statement “default-action reject” to the prefix policy, a prefix that did not match any entry in the
policy will be accepted into LFA SPF.
The no form deletes the exclude prefix policy.
Parameters
prefix-policy prefix-policy — Specifies the name of the prefix policy, up to 32 characters. The
specified name must have been already defined.
mh-secondary-interface
Syntax [ no ] mh-secondary-interface
Context config>router
Description
This command creates a loopback interface for use in multihoming resiliency. This address is
considered the secondary multihoming address and is only used to resolve routes advertised by the
primary router in the event that router becomes unavailable. For this purpose, the reachability for this
address is advertised via IGPs and LDP protocols to allow the resolution of BGP routes advertised
with this address by the primary multihoming router.
The no form of the command disables this setting.
Default no mh-secondary-interface
hold-time
Syntax hold-time holdover-time
no hold-time
Context config>router>mh-secondary-interface
Description The optional hold-time parameter is only applicable for the secondary context and specifies how long
label information leraned about the secondary anycast address should be kept after that peer is
declared down. This timer should be set to a value large enough for the remainder of the network to
detect the failure and complete the reconvergence process.
The no form of the command resets the hold-time back to the default value.
Default
no hold-time
Parameters
holdover-time — Specifies the number of seconds the router should hold label information learned
from the alternate router in its secondary label table. This is to allow the reset of the network to