Command Line Interface
4-142
4
Syntax
[no] {permit | deny} [protocol-number | udp]
{any | source address-bitmask | host source}
{any | destination address-bitmask | host destination}
[source-port sport [end]] [destination-port dport [end]]
[no] {permit | deny} tcp
{any | source address-bitmask | host source}
{any | destination address-bitmask | host destination}
[source-port sport [end]] [destination-port dport [end]]
•protocol-number – A specific protocol number. (Range: 0-255)
•source – Source IP address.
•destination – Destination IP address.
•address-bitmask – Decimal number representing the address bits to matc h.
•host – Keyword followed by a specific IP address.
•sport – Protocol17 source port number. (Range: 0-65535)
•dport – Protocol17 destination port number. (Range: 0-65535)
•end – Upper bound of the protocol port range. (Range: 0-65535)
Default Setting
None
Command Mode
Extended ACL
Command Usage
• All new rules are appended to the end of the list.
• Address bitmasks are similar to a subnet mask, containing four integers from
0 to 255, each separated by a period. The binary mask uses 1 bits to indicate
“match” and 0 bits to indicate “ignore.” The bitmask is bitwise ANDed with the
specified source IP address, and then compared with the address for each IP
packet entering the port(s) to which this ACL has been assigned.
Example
This example accepts any incoming packets if the source addre ss is within subnet
10.7.1.x. For example, if the rule is matched; i.e., the rule (10.7.1.0 & 255.255.255.0)
equals the masked address (10.7.1.2 & 255.255.255.0), the packet passes through.
17. Includes TCP, UDP or other protocol types.
Console(config-ext-acl)#permit 10.7.1.1 255.255.255.0 any
Console(config-ext-acl)#