Can't log in to Magento Admin

Question

I\'m having troubles logging into Magento\'s admin panel on one of our staging sites (it works 100% on our webdev servers and was working just fine not too long ago on the s

Answer 1

Our site was running fine for months, then today no one could log into admin, nor could our users log into their frontend accounts. We run on a linux server.

Solution: the /magento/var/session directory was full of sess_* session files, so many in fact that attempting to execute rm * failed. After a tedious whacking of session files piecemeal (rm sess_1*, rm sess_2*, . . . rm sess_a*, rm sess_b*, . . . rm sess_v*) all of a sudden I could log into Magento again. Actually, I was able to log in after whacking just a few batches.

Theory: when the session directory has too many files, Magento may not be able to create new session files in a timely fashion, or maybe not at all.