Users Guide

seq 50 permit tcp 10.8.0.0 /16 10.50.188.118 /31 eq 49
seq 55 permit udp 10.15.1.0 /24 10.50.188.118 /31 range 1812 1813
To delete a filter, enter the show config command in IP ACCESS LIST mode and locate the sequence number of the filter you want to
delete. Then use the no seq sequence-number command in IP ACCESS LIST mode.
Configure an Extended IP ACL
Extended IP ACLs filter on source and destination IP addresses, IP host addresses, TCP addresses, TCP host addresses, UDP addresses,
and UDP host addresses.
The traffic passes through the filter in the order of the filter’s sequence and hence you can configure the extended IP ACL by first
entering IP ACCESS LIST mode, and then assigning a sequence number to the filter.
Configuring Filters with a Sequence Number
To configure filters with a sequence number, use the following commands.
1. Enter IP ACCESS LIST mode by creating an extended IP ACL.
CONFIGURATION mode
ip access-list extended access-list-name
2. Configure a drop or forward filter.
CONFIG-EXT-NACL mode
seq sequence-number {deny | permit} {ip-protocol-number | icmp | ip | tcp | udp} {source mask
| any | host ip-address} {destination mask | any | host ip-address} [operator port [port]]
[count [byte]] [order] [fragments]
When you use the log keyword, the CP logs details about the packets that match. Depending on how many packets match the log entry
and at what rate, the CP may become busy as it has to log these packets’ details.
Configure Filters, TCP Packets
To create a filter for TCP packets with a specified sequence number, use the following commands.
1. Create an extended IP ACL and assign it a unique name.
CONFIGURATION mode
ip access-list extended access-list-name
2. Configure an extended IP ACL filter for TCP packets.
CONFIG-EXT-NACL mode
seq sequence-number {deny | permit} tcp {source mask | any | host ip-address} [count [byte]]
[order] [fragments]
Configure Filters, UDP Packets
To create a filter for UDP packets with a specified sequence number, use the following commands.
1. Create an extended IP ACL and assign it a unique name.
CONFIGURATION mode
ip access-list extended access-list-name
2. Configure an extended IP ACL filter for UDP packets.
CONFIG-EXT-NACL mode
seq sequence-number {deny | permit} tcp {source mask | any | host ip-address} [count [byte]]
[order] [fragments]
When you create the filters with a specific sequence number, you can create the filters in any order and the filters are placed in the
correct order.
NOTE:
When assigning sequence numbers to filters, you may have to insert a new filter. To prevent reconfiguring
multiple filters, assign sequence numbers in multiples of five or another number.
Access Control Lists (ACLs) 109