Setup Guide

If you are creating a standard prex list with only one or two lters, you can let the system assign a sequence number based on the order in
which the lters are congured. The system assigns lters in multiples of ve.
Creating a Prex List Without a Sequence Number
To create a lter without a specied sequence number, use the following commands.
1 Create a prex list and assign it a unique name.
CONFIGURATION mode
ip prefix-list prefix-name
2 Create a prex list lter with a deny or permit action.
CONFIG-NPREFIXL mode
{deny | permit} ip-prefix [ge min-prefix-length] [le max-prefix-length]
The optional parameters are:
• ge min-prefix-length: is the minimum prex length to be matched (0 to 32).
• le max-prefix-length: is the maximum prex length to be matched (0 to 32).
Example of Creating a Filter with System-Assigned Sequence Numbers
The example shows a prex list in which the sequence numbers were assigned by the software. The lters were assigned sequence
numbers based on the order in which they were congured (for example, the rst lter was given the lowest sequence number). The show
config command in PREFIX LIST mode displays the two lters with the sequence numbers 5 and 10.
Dell(conf-nprefixl)#permit 123.23.0.0 /16
Dell(conf-nprefixl)#deny 133.24.56.0 /8
Dell(conf-nprefixl)#show conf
!
ip prefix-list awe
seq 5 permit 123.23.0.0/16
seq 10 deny 133.0.0.0/8
Dell(conf-nprefixl)#
To delete a lter, enter the show config command in PREFIX LIST mode and locate the sequence number of the lter you want to
delete, then use the
no seq sequence-number command in PREFIX LIST mode.
Viewing Prex Lists
To view all congured prex lists, use the following commands.
• Show detailed information about congured prex lists.
EXEC Privilege mode
show ip prefix-list detail [prefix-name]
• Show a table of summarized information about congured Prex lists.
EXEC Privilege mode
show ip prefix-list summary [prefix-name]
Examples of the show ip prefix-list Commands
The following example shows the show ip prefix-list detail command.
Dell>show ip prefix detail
Prefix-list with the last deletion/insertion: filter_ospf
ip prefix-list filter_in:
count: 3, range entries: 3, sequences: 5 - 10
136
Access Control Lists (ACLs)