Setup Continues

Apache has been stripped down to the basic, nearly all modules have been removed except PHP5 which has reduced the memory usage significantly.

I have decided to use nginx to serve static content and this has now been setup on both linodes. I have worked out how to deal with both servers generating static files and how to sync them between the two linodes.

Redis will be used to monitor the most active elements of the website. A key will be created for each item ID accessed with an expire time, if another request is made for the same item within X minutes, the key value will be incremented like a hit counter and the expire time renewed. This will provide very efficient monitoring of the most active items on the site at all times.

The redis activity monitor will initially be used to populate a 'whats hot' view on the website but also to increase the rate at which active items are recached.

Additionally I've changed all ssh logins to public/private key to remove password vulnerabilities.
I got a tip from the very helpful guys in the linode.com IRC chat about cache files and syncing. They recommended writing the cache to a temp file name then renaming rather than copying - this is very efficient all round.

Firewalls have been configured, everything except http and ssh has been locked out on the public interfaces. Private interfaces allow a little more, but not much.