Cisco Systems OL-15491-01 appendix Match header host1 *.2.*.44, Convention Description, 168

Appendix A CSG2 Command Reference

match header

Usage Guidelines This command is valid only for HTTP and Session Initiation Protocol (SIP).

You can use more than one match header command in CSG2 map configuration mode to specify multiple header match patterns for a header map as follows:

•You can configure more than one match header command in a given header map, but they must reference different headers.

For example, the following is a valid configuration, because the first match header command references header Host and the other references header User-Agent:

ip csg map HDR1

match header Host www.cisco.com

match header User-Agent myagent

But the following is not a valid configuration, because both match header commands reference header Host:

ip csg map HDR1

match header Host www.cisco.com

match header Host my.cisco.com

•If a flow matches all of a map’s header match patterns, then the CSG2 accepts and processes the flow (unless another map associated with the flow does not match, of course).

•If a flow does not match even one of a map’s header match patterns, then the match fails and the CSG2 does not accept or process the flow.

•The CSG2 treats each header match pattern as a double-wildcard match, which means that a header match pattern that includes even a single wildcard, such as match header host* 1.2.3.4, is treated as a triple-wildcard match. The more wildcard matches you use, the fewer header maps and header match patterns the CSG2 can handle, depending on your configuration. Therefore, to optimize the performance of the CSG2, minimize the number of header match patterns that are applied to a CSG2 content configuration, and minimize the number of wildcards used in header match patterns.

•By default, the header match patterns are case-sensitive. For example, if you define the following header match pattern:

match header host1 *.2.*.44

but the actual HTTP header keyword is HOST1, then the match fails and the CSG2 does not accept or process the flow.

If you do not want the header match patterns to be case-sensitive, configure the no ip csg case-sensitivecommand.

You can specify up to 8192 match patterns.

The following table shows and describes the special characters that you can use in the value argument in header match patterns.

Convention	Description
*	Zero or more characters.
+	Zero or more repeated instances of the token preceding the +.
?	Zero or one character.

	Cisco Content Services Gateway - 2nd Generation Release 2.0 Installation and Configuration Guide
A-168	OL-15491-01