Streaming Media Supplement sa2150 and sa2250

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Chapter 10 Logging and Monitoring
By default, then, Squid logging is disabled in Media-IXT, but enabled in Traffic Server. In other words, Squid
logging is disabled for streaming media protocols but enabled for HTTP.
Squid logging is enabled for Traffic Server, when the configuration variable
proxy.config.log2.squid_log_enabled in records.config is set to 1. You can also enable
and disable Squid logging for Traffic Server through Traffic Manager. See the HP Cache Server Appliance
Administrator Guide for details.
Keep in mind that the separate_mixt_logs variable affects streaming media logging only.
Distinguishing RealNetworks from QuickTime in log entries
Because RealNetworks and QuickTime both use the RTSP protocol for streaming, you can not tell whether a
logging entry is for one or the other type of content on the basis of URL scheme alone. Instead, make use of the
knowledge that the file extensions typically used by RealNetworks streaming content files differ from those
used by QuickTime.
• QuickTime’s usual file extensions are:
o .sdp for live QuickTime content
o .mov for on-demand QuickTime content
RTSP streaming files with extensions other than .sdp and .mov are likely to be RealNetworks content.
Reverse proxy logging
In a reverse proxy caching deployment where Media-IXT answers to the advertised name of a website:
• a client directs a request to the advertised website name, also known as the unmapped URL
• Media-IXT receives the request
• in its reverse proxy configuration files, Media-IXT finds the origin server to which the advertised website
name is mapped
• Media-IXT then rewrites the request's destination URL to that of the origin server, also known as the
mapped URL
In this way, the client's request makes its way to the appropriate origin server. Media-IXT’s rewriting of the
URL, though, raises a question about logging: should Media-IXT log the request as having the mapped URL,
or the unmapped URL?
You can configure Media-IXT to do either, by means of a variable in the records.config file.
This variable is
proxy.config.url_remap.pristine_host_hdr
and it behaves like this:
• by default, proxy.config.url_remap.pristine_host_hdr is 0 (zero), and Media-IXT logs
the mapped URL
• if you set proxy.config.url_remap.pristine_host_hdr to 1, Media-IXT logs the unmapped
URL
This variable applies to HTTP as well as other protocols, and is documented in the HP Cache Server Appliance
Administrator Guide. See that guide for a configuration procedure.
Logging and SMIL files
The SMIL (pronounced “smile”) file is a kind of index file that invokes other files, including both streaming
media files (like movie files) and various types of multimedia files (like JPEG or GIF image files). SMIL stands
for Synchronized Multimedia Integration Language, and SMIL files are text files specifying how and when the
invoked files should play.