Access Control List Commands
4-89
4
Example
Related Commands
permit, deny 4-89
ip access-group (4-97)
show ip access-list (4-92)
permit, deny (Standard ACL)
This command adds a rule to a Standard IP ACL. The rule sets a filter condition for
packets emanating from the specified source. Use the no form to remove a rule.
Syntax
[no]{permit | deny}{any|source bitmask | host source}
•any – Any source IP address.
•source – Source IP address.
•bitmask – Decimal number representing the address bits to match.
•host – Keyword followed by a specific IP address.
Default Setting
None
Command Mode
Standard ACL
Command Usage
• 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 configures one permit rule for the specific address 10.1.1.21 and
another rule for the address range 168.92.16.x – 168.92.31.x using a bitmask.
Related Commands
access-list ip (4-88)
Console(config)#access-list ip standard david
Console(config-std-acl)#
Console(config-std-acl)#permit host 10.1.1.21
Console(config-std-acl)#permit 168.92.16.0 255.255.240.0
Console(config-std-acl)#