This is an environment that has been up for a couple of years, currently consisting of (virtual machines) 1 web (14.04 LTS Ubuntu), 1 db (12.04 LTS Ubuntu) and finally 1 mail (14.04 LTS Ubuntu). All servers have db for ispconfig, otherwise all db is on db-server. Tonight I couldn't log into ispconfig admin interface (https:// server: 8080), I can access the site but not log in. This is not directly connected to any new updates etc, a couple of days ago everything worked fine. I get following error in apache error log: mod_fcgid: stderr: PHP Warning: session_start(): Failed to decode session object. Session has been destroyed in /usr/local/ispconfig/interface/lib/app.inc.php on line 104, referer: xxxxxx So looking at the handling of sessions for ispconfig web interface, it's rather special. Anyway, it seems that a new row is written in sys_session, and session_id is same as actual session id in browser. The issue seems to be the session_data field, where I think that the serialized data somehow cuts off (or it's just me getting tired). EDIT: That was probably just me getting tired, once removed s| at start that part worked just fine. I couldn't find any topics regarding this issue, and I don't really know how to solve it. Any tips would be nice. Ps. In a rather desperate move I tried to update web server, including updating ispconfig (from p8 to p9 using update script, so nothing really changed). But it didn't help. Ps2. Everything else on server seems to work just fine.