Brocade Communications Systems ICX 7250 series, Руководство по настройке

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Neighbor database
Neighbor information is updated in the standby module based on updates from the active module. Certain neighbor state and interface
transitions are synchronized to the standby module. By default, the neighbor timers on the standby module are disabled.
LSA database
The standby module processes LSA synchronization events from the active module and unpacks the LSA synchronization information to
directly install it in its LSDB, as the LSA has already been processed on the active module. The information required to install all types of
LSAs (and special LSAs such as Grace LSAs) is packed by OSPF on the active module in the synchronization buffer, so that you can
directly install LSAs on the standby module without extra processing.
The standby module is not allowed to originate any LSAs of its own. This is to maintain all information consistently from the active
module. The active module synchronizes self-originated LSAs to the standby module.
LSA aging is not applicable on the standby module. During synchronization from the active module, the current LSA age is recorded and
the new database timestamp is created on the standby module to later derive the LSA age as needed.
When the active module sends the LSAs to the standby module, based on the message, the standby module deletes or updates its
LSDB with the latest information.
LSA acknowledging or flooding are not done on the standby module. When the LSA synchronization update arrives from the active
module, it will be directly installed into the LSDB.
OSPFv2 distribute list
A distribution list can be configured to explicitly deny specific routes from being eligible for installation in the IP route table. By default, all
OSPFv2 routes in the OSPFv2 route table are eligible for installation in the IP route table. Receipt of LSAs are not blocked for the denied
routes. The device still receives the routes and installs them in the OSPFv2 database. The denied OSPFv2 routes cannot be installed into
the IP route table.
The OSPFv2 distribution list can be managed using ACLs or route maps to identify routes to be denied as described in the following
sections:
• Configuring an OSPFv2 Distribution List using ACLs
• Configuring an OSPFv2 Distribution List using route maps
Configuring an OSPFv2 distribution list using ACLs
To configure an OSPFv2 distribution list using ACLs:
• Configure an ACL that identifies the routes you want to deny. Using a standard ACL allows you deny routes based on the
destination network, but does not filter based on the network mask. To also filter based on the network mask of the destination
network, use an extended ACL.
• Configure an OSPFv2 distribution list that uses the ACL as input.
Examples
In the following configuration example, the first three commands configure a standard ACL that denies routes to any 10.x.x.x destination
network and allows all other routes for eligibility to be installed in the IP route table. The last three commands change the CLI to the
OSPFv2 configuration level and configure an OSPFv2 distribution list that uses the ACL as input. The distribution list prevents routes to
OSPFv2 distribute list
Brocade FastIron Layer 3 Routing Configuration Guide
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