Administrator Guide
Conguring Filters with a Sequence Number
To congure 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 Congure 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.
Congure Filters, TCP Packets
To create a lter for TCP packets with a specied 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 Congure 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]
Congure Filters, UDP Packets
To create a lter for UDP packets with a specied 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 Congure an extended IP ACL lter for UDP packets.
CONFIG-EXT-NACL mode
seq sequence-number {deny | permit} tcp {source mask | any | host ip-address} [count [byte]]
[order] [fragments]
Example of the seq Command
When you create the lters with a specic sequence number, you can create the lters in any order and the lters are placed in the correct
order.
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Access Control Lists (ACLs)