Users Guide

Congure an Extended IP ACL
Extended IP ACLs lter on source and destination IP addresses, IP host addresses, TCP addresses, TCP host addresses, UDP addresses,
and UDP host addresses.
Because trac passes through the lter in the order of the lter’s sequence, you can congure the extended IP ACL by rst entering IP
ACCESS LIST mode and then assigning a sequence number to the lter.
Conguring Filters with a Sequence Number
To congure lters 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 Congure a drop or forward lter.
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.
Congure Filters, TCP Packets
To create a lter for TCP packets with a specied 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 Congure an extended IP ACL lter for TCP packets.
CONFIG-EXT-NACL mode
seq sequence-number {deny | permit} tcp {source mask | any | host ip-address}} [count [byte]]
[order] [fragments]
Congure Filters, UDP Packets
To create a lter for UDP packets with a specied 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 Congure an extended IP ACL lter for UDP packets.
CONFIG-EXT-NACL mode
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Access Control Lists (ACLs)