My site is going down once or twice a day when it starts throwing the exception \"Front controller reached 100 router match iterations\". Once this happens access to the adm
This message is caused by bad cached config data. I'm not sure what actually causes the cached config to become corrupted - I would guess it could be a number of things that would vary depending on how Magento is running.
I guess, if you can still get to the Magento backend, you can trying clearing cache under System > Cache Management. If that doesn't help (or if you can't get to the Magento backend, which is likely with this error), then determine how your caching is set up by finding the value of < cache >< backend > in app/etc/local.xml. If you're using files for cache (the default), can you can clear out magento/var/cache with
rm -rf /path/to/magento/var/cache/*
If you're using memcached, find the port under < port > and you can do
telnet memcache_server portnumber
flush_all
Or if you're using redis, you can do
telnet redis_server portnumber
FLUSHALL