Defining Filters; Prerequisites; Defining An Ip-Prefix List - 3Com 4500G Family Configuration Manual

Defining Filters

Configuring a Route Policy
Defining Filters

Prerequisites

Before configuring this task, you need to decide on:
IP-prefix list name
Matching address range

Defining an IP-prefix List

Define an IPv4 prefix list
Identified by name, an IPv4 prefix list can comprise multiple items. Each item specifies a prefix range to
match and is identified by an index number.
An item with a smaller index number is matched first. If one item is matched, the IP prefix list is passed,
and the routing information will not go to the next item.
Follow these steps to define an IPv4 prefix list:
To do...
Enter system view
Define an IPv4 prefix
list
If all the items are set to the deny mode, no routes can pass the IPv4 prefix list. Therefore, you need to
define the permit 0.0.0.0 0 less-equal 32 item following multiple deny items to allow other IPv4 routing
information to pass.
For example, the following configuration filters routes 10.1.0.0/16, 10.2.0.0/16 and 10.3.0.0/16, but
allows other routes to pass.
<Sysname> system-view
[Sysname] ip ip-prefix abc index 10 deny 10.1.0.0 16
[Sysname] ip ip-prefix abc index 20 deny 10.2.0.0 16
[Sysname] ip ip-prefix abc index 30 deny 10.3.0.0 16
[Sysname] ip ip-prefix abc index 40 permit 0.0.0.0 0 less-equal 32
Task
Defining an IP-prefix List
Creating a Route Policy
Defining if-match Clauses
Defining apply Clauses
Use the command...
system-view
ip ip-prefix ip-prefix-name [ index
index-number ] { permit | deny } ip-address
mask-length [ greater-equal min-mask-length ]
[ less-equal max-mask-length ]
1-3
Remarks
—
Required
Not defined by default.