= phenomenon =
app07 would return a global mirrorlist to users on IPv6, rather than the country-specific list that would be expected.
= reason =
app07 /usr/share/GeoIP/ database was not current, and did not include the IPv6 database. The files were stale from September 1, 2009, rather than updated monthly as expected. It's unclear why app07 has not been syncing its copy of the databases monthly. Its root crontab includes:
0 1 4 * * /usr/local/bin/syncFiles.sh geoip /usr/share/GeoIP/
as expected. Manually executing this succeeded.
In addition, all the other app servers had databases still from December 2009 rather than January 2010. This may be due to the cronjob on bapp01 not running on January 4, 2010, I don't know.
= recommendation =
manually execute the above cronjob on all app servers (done).
Investigate why app07 was not executing that cronjob.
app07 was rebuilt, after January 4, so it missed executing the Jan 4 cronjob. The stale GeoIP.dat file came from the GeoIP RPM - it gets overwritten by the monthly cronjob.
Mystery solved, with help from G.
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