Implementation Information; Configuration Task List For Prefix Lists; Configure A Prefix List - Dell Force10 MXL Blade Configuration Manual

The following rules apply to prefix lists:
• A prefix list without any permit or deny filters allows all routes.
• An "implicit deny" is assumed (that is, the route is dropped) for all route prefixes that do not match a
permit or deny filter in a configured prefix list.
• After a route matches a filter, the filter's action is applied. No additional filters are applied to the route.

Implementation Information

In FTOS, prefix lists are used in processing routes for routing protocols (for example, router information
protocol [RIP], open shortest path first [OSPF], and border gateway protocol [BGP]).
Note: The MXL Switch platform does not support all protocols. It is important to know which protocol you
are supporting prior to implementing prefix lists.

Configuration Task List for Prefix Lists

To configure a prefix list, you must use commands in PREFIX LIST, ROUTER RIP, ROUTER OSPF, and
ROUTER BGP modes. You create the prefix list in PREFIX LIST mode, and assign that list to commands
in ROUTER RIP, ROUTER OSPF, and ROUTER BGP modes.
The following list includes the configuration tasks for prefix lists:
•

Configure a Prefix List

• Use a Prefix List for Route Redistribution
For a complete listing of all commands related to prefix lists, refer to the FTOS Command Line Interface
Reference Guide.
Configure a Prefix List
To configure a prefix list, follow these steps, starting in CONFIGURATION mode:
Step Command Syntax
1 ip prefix-list prefix-name
2
seq sequence-number {deny |
permit} ip-prefix [ge
min-prefix-length] [le
max-prefix-length]
86
| Access Control Lists (ACLs)
Command Mode
CONFIGURATION
CONFIG-NPREFIXL
Purpose
Create a prefix list and assign it a unique
name.
You are in PREFIX LIST mode.
Create a prefix list with a sequence number
and a deny or permit action. The optional
parameters are:
• is the minimum
ge min-prefix-length:
prefix length to be matched (0 to 32).
• is the maximum
le max-prefix-length:
prefix length to be matched (0 to 32).