Policy Framework Configuration Guide - Juniper Networks

Junos 10.4 Policy Framework Configuration Guide
}
}
In the standard configuration database, configure policy-statement one based on the
policy with the same name configured in the dynamic database. In addition, configure
prefix-list pl2, which references the prefix list with the same name in the dynamic database,
and configure policy-statement two, which references prefix-list pl2.
[edit]
policy-options {
prefix-list pl2;
dynamic-db; # Reference ’prefix-list pl2’ configured in the dynamic database.
}
policy-statement two {
term term1 {
from {
prefix-list pl2; # Configure a routing policy that includes a prefix list that
# references the dynamic database.
}
then accept;
}
then reject;
}
policy-statement one;
dynamic-db; # Configure a policy in the standard configuration that references
# the policy configured in the dynamic database.
}
}
Apply a policy expression that includes routing policies one and two to BGP export policy
for an internal BGP group test.
[edit]
protocols {
bgp {
group test;
type internal;
local-address 10.255.245.44;
export ( one && two ); # If routing policy one returns the value of TRUE, policy # two
is evaluated.
# If policy one returns the value of FALSE, the evaluation of the expression # ends
and policy two is not evaluated.
}
}
}
Forwarding Packets to the Discard Interface
The discard interface allows you to protect a network from denial-of-service (DoS)
attacks by identifying the target IP address that is being attacked and configuring a policy
to forward all packets to a discard interface. All packets forwarded to the discard interface
are dropped.
To configure the discard interface, include the dsc statement:
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