[Contents] [Prev] [Next] [Index] [Report an Error]

Defining Prefix Lists

You can create a named prefix list and include it in a routing policy with the prefix-list match condition (described in Table 14).

To define a prefix list, include the prefix-list statement:




prefix-list prefix-list-name {
apply-path path;

ip-addresses;
}

You can include this statement at the following hierarchy levels:

[edit policy-options]
[edit logical-systems logical-system-name policy-options]

You can use the apply-path statement to include all prefixes pointed to by a defined path, or you can specify one or more addresses, or both.

To include a prefix list in a routing policy, specify the prefix-list match condition in the from statement at the [edit policy-options policy-statement policy-name term term-name] hierarchy level:



[edit policy-options policy-statement policy-name term term-name]
from {

prefix-list prefix-list-name; 
}
then actions;

name identifies the prefix list. It can contain letters, numbers, and hyphens (-) and can be up to 255 characters long. To include spaces in the name, enclose the entire name in quotation marks (“ ”).

ip-addresses are the IPv4 or IP version 6 (IPv6) prefixes specified as prefix/prefix-length. If you omit prefix-length for an IPv4 prefix, the default is /32. If you omit prefix-length for an IPv6 prefix, the default is /128. Prefixes specified in a from statement must be either all IPv4 addresses or all IPv6 addresses.

Note: You cannot apply actions to individual prefixes in the list.

You can specify the same prefix list in the from statement of multiple routing policies or firewall filters. For information about firewall filters, see Configuring Firewall Filters.

Use the apply-path statement to configure a prefix list comprising all IP prefixes pointed to by a defined path. This eliminates most of the effort required to maintain a group prefix list.

The path consists of elements separated by spaces. Each element matches a configuration keyword or an identifier, and you can use wildcards to match more than one identifier. Wildcards must be enclosed in angle brackets, for example, <*>.

Note: When you use apply-path to define a prefix list, you can also use the same prefix list in a policy statement.

For examples of configuring a prefix list, see Example: Configuring a Prefix List; for examples of configuring a firewall filter, see Configuring Firewall Filters.

[Contents] [Prev] [Next] [Index] [Report an Error]