Discussion

If the route or packet does not match any of the conditions when the end of the policy
or filter is reached, a default action is taken.
A routing policy can have several match conditions, with multiple conditions in a
single term, with several terms in the same policy, or with several policies chained
together. Similarly, a firewall filter can have a number of match conditions. However,
you can apply only one firewall filter on an input or output interface. To have a
series of match conditions, you define multiple matches in a term or multiple terms
in a single filter.
Applying Policies and Filters
After defining a policy or filter, you apply it to a protocol or interface. For a policy,
you use import and export statements. An import policy applies when the router is
evaluating routes received from a routing protocol before placing them into the routing
table. An export policy applies when an active route in the routing table is sent in
a routing-protocol advertisement. For a firewall filter, you use filter input and
filter output statements for incoming and outgoing traffic on an interface.
9.1 Creating a Simple Routing Policy
Problem
You want to advertise configured static routes to adjacent OSPF neighbors, going
beyond the OSPF default of advertising only the routes learned from an OSPF
neighbor.
Solution
To modify the route advertisement behavior, create and apply a routing policy. First,
create the policy:
[edit]
aviva@router1# set policy-options policy-statement send-statics term 1 from protocol
static
aviva@router1# set policy-options policy-statement send-statics term 1 then accept
Then, apply it to OSPF:
[edit]
aviva@router1# set protocols ospf export send-statics
Here’s what the policy looks like in the configuration:
[edit]
aviva@router1# show
policy-options {
policy-statement send-statics {
term 1 {
from protocol static;
284 | Chapter 9: Routing Policy and Firewall Filters
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