Users Guide

To delete a lter, enter the show config command in IP ACCESS LIST mode and locate the sequence number of the lter you want to
delete. Then use the no seq sequence-number command in IP ACCESS LIST mode.
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.
The trac passes through the lter in the order of the lter’s sequence and hence 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 [portnumber |
portname]] [count [byte]] [order] [monitor [session-id]] [fragments]
While conguring an IP access list, you can choose to congure either by using the logical name of the protocol or by using the port
number of the protocol. The logical names are available for both TCP and UDP.
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.
Example for conguring the IP access list using port numbers and protocol names:
Dell(config-ext-nacl)# seq 25 permit tcp any eq 40 any eq 33
Dell(config-ext-nacl)# seq 30 permit tcp any eq 33 any eq 43
Dell(config-ext-nacl)# seq 35 permit tcp any range www 194 any eq 101
Dell(config-ext-nacl)# seq 40 permit udp any eq 434 any gt mobile-ip
Dell(config-ext-nacl)# seq 45 deny udp any eq 53 any lt ntp
Dell(config-ext-nacl)#
Dell(config-ext-nacl)#show config
!
ip access-list extended vv
seq 25 permit tcp any eq 40 any eq 33
seq 30 permit tcp any eq 33 any eq 43
seq 35 permit tcp any range www 194 any eq 101
seq 40 permit udp any eq 434 any gt mobile-ip
seq 45 deny udp any eq 53 any lt ntp
Congure Filters, ICMP Packets
To create a lter for ICMP packets with a specied sequence number, use the following commands.
1 Create either an extended IPv4 or IPv6 ACL and assign it a unique name.
CONFIGURATION mode
ip access-list extended access-list-name
Access Control Lists (ACLs)
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