[squid-users] Re: Troubleshooting Squid [Was: clientReadRequest FD18: (27) File too large]

Some documentation you and others needing to troubleshoot Squid should
be aware of:

squid.conf.default documentation:

cache_log

        Cache logging file. This is where general information about
        your cache's behavior goes. You can increase the amount of data
        logged to this file with the "debug_options" tag below.

debug_options

        Logging options are set as section,level where each source file
        is assigned a unique section. Lower levels result in less
        output, Full debugging (level 9) can result in a very large
        log file, so be careful. The magic word "ALL" sets debugging
        levels for all sections. We recommend normally running with
        "ALL,1".

Squid command line arguments:

-d level
        Debugging level for ``stderr'' messages. If you use this option,
        then debugging messages up to the specified level will also be
        written to stderr. [FAQ]

        Write debugging to stderr also. [squid -h]
        
Squid FAQ 11.20 Debugging Squid

        If you believe you have found a non-fatal bug (such as incorrect
        HTTP processing) please send us a section of your cache.log with
        debugging to demonstrate the problem. The cache.log file can
        become very large, so alternatively, you may want to copy it to
        an FTP or HTTP server where we can download it.

        It is very simple to enable full debugging on a running squid
        process. Simply use the -k debug command line option:

                % ./squid -k debug

        This causes every debug() statement in the source code to write
        a line in the cache.log file. You also use the same command to
        restore Squid to normal debugging.

        To enable selective debugging (e.g. for one source file only),
        you need to edit squid.conf and add to the debug_options line.
        Every Squid source file is assigned a different debugging
section.
        The debugging section assignments can be found by looking at the
        top of individual source files, or by reading the file
        doc/debug-levels.txt (correctly renamed to debug-sections.txt
        for Squid-2). You also specify the debugging level to control
        the amount of debugging. Higher levels result in more debugging
        messages. For example, to enable full debugging of Access
Control
        functions, you would use

                debug_options ALL,1 28,9

        Then you have to restart or reconfigure Squid.

        Once you have the debugging captured to cache.log, take a look
at
        it yourself and see if you can make sense of the behaviour which
        you see. If not, please feel free to send your debugging output
        to the squid-users or squid-bugs lists.

Regards
Henrik

bernhard.kreinz@zkb.ch wrote:

> We had a problem with a cache server. For troubleshooting purposes an
> engineer set the debug level to All,9. The Masterproxy then went down
> every 30 to 50 minutes.
>
> From then on the story went to this mailing-list. A hint to a filesize
> limit of 2GB and a request to see the filesizes of access.log, cache.log
> and store.log was the right way to get this problem away.
>
> The relationship between a high debug_level and the cache.log was not
> evident. We watched the error.log for debug output and not the cache.log !
Received on Tue Mar 26 2002 - 04:16:35 MST