Policy Framework Configuration Guide - Juniper Networks

Junos 10.4 Policy Framework Configuration Guide
NOTE: If you are downgrading the Junos OS to Junos OS Release 9.4 or earlier,
you must first delete any routing policies that reference the dynamic database.
That is, you must delete any routing policies or policy objects configured with
the dynamic-db statement.
Applying Dynamic Routing Policies to BGP
BGP is the only routing protocol to which you can apply routing policies that reference
the dynamic database configuration. You must apply these policies in the standard
configuration. Dynamic policies can be applied to BGP export or import policy. They can
also be applied at the global, group, or neighbor hierarchy level.
To apply a BGP export policy, include the export [ policy-names ] statement at the [edit
protocols bgp], [edit protocols bgp group group-name], or [edit protocols bgp group
group-name neighbor address] hierarchy level.
[edit]
protocols
bgp {
export [ policy-names ];
}
}
To apply a BGP import policy, include the import [ policy-names ] statement at the [edit
protocols bgp], [edit protocols bgp group group-name], or [edit protocols bgp group
group-name neighbor address] hierarchy level.
[edit]
protocols
bgp {
import [ policy-names ];
}
}
Include one or more policy names configured in that standard configuration at the [edit
policy-options policy-statement] hierarchy level that reference policies configured in the
dynamic database. For more general information about configuring BGP import and
export policy, see the Junos Routing Protocols Configuration Guide.
Preventing Reestablishment of BGP Peering Sessions After NSR Routing Engine Switchover
If you have active nonstop routing (NSR) enabled, the dynamic database is not
synchronized with the backup Routing Engine. As a result, if a switchover to a backup
Routing Engine occurs, import and export policies running on the master Routing Engine
at the time of the switchover might no longer be available. Therefore, you might want to
prevent a BGP peering session from automatically being reestablished as soon as a
switchover occurs.
You can configure the router not to reestablish a BGP peering session after an active
nonstop routing switchover either for a specified period or until you manually reestablish
the session. Include the idle-after-switch-over (seconds | forever) statement at the [edit
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