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Catalyst 2950 and Catalyst 2955 Switch Software Configuration Guide
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Chapter 28 Configuring Network Security with ACLs
Configuring ACLs
Note For information about creating ACLs to apply to management interfaces, see the “Configuring IP
Services” section of Cisco IOS IP and IP Routing Configuration Guide, Release 12.1 and the Cisco IOS
IP and IP Routing Command Reference, Cisco IOS Release 12.1. You can apply ACLs only to a
management interface or the CPU, such as SNMP, Telnet, or web traffic.
Beginning in privileged EXEC mode, follow these steps to create an extended ACL:
Command Purpose
Step 1 configure terminal Enter global configuration mode.
Step 2 access-list access-list-number
{deny | permit | remark} protocol
{source source-wildcard | host
source | any} [operator port]
{destination destination-wildcard |
host destination | any} [operator
port] [dscp dscp-value]
[time-range time-range-name]
Define an extended IP access list and the access conditions.
The access-list-number is a decimal number from 100 to 199 or 2000 to 2699.
Enter deny or permit to specify whether to deny or permit the packet if
conditions are matched.
For protocol, enter the name or number of an IP protocol: IP, TCP, or UDP. To
match any Internet protocol (including TCP and UDP), use the keyword ip.
The source is the number of the network or host from which the packet is sent.
The source-wildcard applies wildcard bits to the source.
The destination is the network or host number to which the packet is sent.
Define a destination or source port.
The operator can be only eq (equal).
If operator is after source source-wildcard, conditions match when the
source port matches the defined port.
If operator is after destination destination-wildcard, conditions match
when the destination port matches the defined port.
The port is a decimal number or name of a TCP or UDP port. The number
can be from 0 to 65535.
Use TCP port names only for TCP traffic.
Use UDP port names only for UDP traffic.
The destination-wildcard applies wildcard bits to the destination.