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We have many "known data hit, don't write to" messages in
/var/log/apt-cacher-ng/apt-cacher.err. The file had 51,462 lines
covering exactly two years.<br>
<br>
A random sample of lines showed few messages per day (some days no
messages), most caused by loss of Internet connectivity and the same
few repositories that were not DNS resolvable.<br>
<br>
Then, on 23 May 2013 the first of many messages like these ...<br>
<br>
<font face="monospace">Thu May 23 15:35:36 2013|known data hit,
don't write to...<br>
Thu May 23 15:35:36
2013|/var/cache/apt-cacher-ng/changelogs.ubuntu.com/meta-release-lts</font><br>
<br>
... after which they dominate the log, comprising 51,348 of its
51,462 lines.<br>
<br>
Searching the Internet for these messages got only nine hits, most
not related. From
<a class="moz-txt-link-freetext" href="http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=622272">http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=622272</a>:<br>
<br>
> And in the server logs:<br>
><br>
> Wed May 25 17:02:43 2011|known data hit, don't write to...<br>
> Wed May 25 17:02:43
2011|/var/cache/apt-cacher-ng/debrep/dists/unstable/InRelease<br>
<br>
Normal behavior. The upstream mirror was asked to resume a file
download<br>
(with date check) and the cached file had the same length and
same (or<br>
more recent) date as the remote file.<br>
<br>
I still suspect incorrect clock settings on the client or on the
proxy<br>
machine, or maybe a bad mirror which is no longer uptodate.<br>
<br>
Regards the clock, ntpd is running on the server and the time by
manual comparison is identical to the other servers.<br>
<br>
Regards a bad mirror, we have no record of how the acng
configuration has been changed since installation. There's only one
config file with a ~ suffix, suggesting it has been edited;
"backends_debian~" is an empty file; "backends_debian" lists
<a class="moz-txt-link-freetext" href="http://ftp.au.debian.org/debian/">http://ftp.au.debian.org/debian/</a>. I could re-install the packages
config files to ensure a default config.<br>
<br>
Versions: <br>
<tt># uname -a</tt><tt><br>
</tt><tt>Linux backupserver 3.2.0-4-amd64 #1 SMP Debian 3.2.41-2
x86_64 GNU/Linux</tt><tt><br>
</tt><tt># aptitude show apt-cacher-ng | grep ^Version</tt><tt><br>
</tt><tt>Version: 0.7.11-1</tt><br>
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