Streaming Media Supplement sa2150 and sa2250

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Chapter 9 Configuring Media-IXT for QuickTime
Two configuration files control selective caching:
• cache.config controls cacheability
• filter.config controls proxyability
You must edit cache.config and filter.config manually, adding selective caching rules to the files.
You can, optionally, add an RNI or QT tag to any selective caching rule. This permits you to apply one rule to
QuickTime content and another for RealNetworks content. The format for the tag is to add tag= to the end of
the rule, followed by the tag value of RNI or QT. See the HP Cache Server Appliance Administrator Guide for
details how rules are applied in situations where there is no tag added to a rule, or when conflicting rules apply
to the same request.
The kinds of selective caching rules you can write for RealNetworks and QuickTime differ from those you can
write for WMT. For RealNetworks and QuickTime, always use hostnames (in Fully Qualified Domain Name
form), not IP addresses, in selective caching rules.
After you modify the cache.config or filter.config, Media-IXT must reread its configuration files.
From Media-IXT’s bin directory, run the command:
./traffic_line -x
This section provides an overview of selective caching with an emphasis on QuickTime-specific issues that do
not appear in the HP Cache Server Appliance Administrator Guide.
Modifying the filter.config file to determine proxyability
To add a new rule to filter.config, you need exactly one primary specifier, may add one or more
secondary specifier, and must choose one of two possible actions.
The primary specifier
The primary specifier must be one of the following:
• dest_domain, meaning domain suffix of sites.
Example: where the desired domain suffix of sites is hp.com, the rule appears in filter.config like
this:
dest_domain=hp.com
• dest_host, meaning fully qualified domain name of host.
Example: where the desired hostname is tsdev.hp.com, the rule appears in filter.config like
this:
dest_host=tsdev.hp.com
• url_regex, meaning a regular expression, which can appear anywhere in the URL (in other words, the
expression video will match with the URL rtsp://pow.quickcom/qtvideo.rm).
Example: where the desired regular expression is video
,
the rule appears in filter.config like this:
url_regex=video
For url_regex, note that / is a special control character. This, and some other special control characters.
must be escaped. For example, if you want to match the pattern cars/mustang, your rule would be:
url_regex=cars\/mustang
For details, check a book or web site that discusses regular expressions. At this writing, one such site is:
http://etext.lib.virginia.edu/helpsheets/regex.html