Names and Name Commands

You can create and use text names for IP addresses in much the same way the IP Host command can be used on conventional routers. The name command is used to associate a single IP address and a text name. The names created become a host table local to that specific PIX Firewall only. You must first use the names command before immediately using the name command. Both the names command and any name statements created are saved in the configuration. The syntax is

Pix(config)# names
Pix(config)# name ip_address name

The clear names command clears the list of names from the PIX Firewall configuration. The no names command disables the use of the text names, but doesn’t remove them from the configuration. The show names command lists the name command statements in the configuration. The following output shows the commands to create three names, the show names command, and the result of a write terminal command.

Pix(config)# names
Pix(config)# name 1.1.1.1 pix_out
Pix(config)# name 192.168.1.1 pix_in
Pix(config)# name 192.168.2.1 pix_dmz
Pix(config)# 
Pix(config)# show names
name 1.1.1.1 pix_out
name 192.168.1.1 pix_in
name 192.168.2.1 pix_dmz
Pix(config)#
Pix(config)# write t
Building configuration...
   (output omitted)
names
name 1.1.1.1 pix_out
name 192.168.1.1 pix_in
name 192.168.1.1 pix_in
   (output omitted)
Pix(config)#

The next output shows using the name with the ping command, instead of the IP address.

The next output shows the PIX Firewall assumes you prefer the name and substitutes the name for the address(es) whenever appropriate.

Pix(config)# show ip addresses
System IP Addresses:
        ip address outside pix_out 255.255.255.0
        ip address inside pix_in 255.255.255.0
        ip address dmz pix_dmz 255.255.255.0
Current IP Addresses:
        ip address outside pix_out 255.255.255.0
        ip address inside pix_in 255.255.255.0
        ip address dmz pix_dmz 255.255.255.0
Pix(config)#

Remember the following about name implementations:

• Only one name can be associated with an IP address.

• Names can use the characters a to z, A to Z, 0 to 9, the dash, and the underscore, but no spaces. The name can’t be longer than 16 characters or start with a number.

• One reason to create names is to make life easier. Make sure the names you create don’t add another level of complexity. The previous names could have been out, in, and dmz. Before you create names, make sure they won’t look like keywords or instructions.