Warning: Unknown: open(/tmp/sess_f834b2b8b63fbd78ef78ca796e6c, O_RDWR) failed: Read-only file system (30) in Unknown on line 0

today i tried to access my dedicated server that was provide by www.webune.com when i tried to login to my website, i kept getting this erro:

CODE:
Warning: session_start() [function.session-start]: Cannot send session cache limiter - headers already sent (output started at web/login.php:29) in /web/login.php on line 29


so then i tried to login to phpmyadmin and then i got this error all over the page after i logged in:

CODE:
Warning: Unknown: Failed to write session data (files). Please verify that the current setting of session.save_path is correct (/tmp) in Unknown on line 0


and this one:

CODE:
Warning: Unknown: open(/tmp/sess_f834b2b8b63fbd78ef78ca73e8996e6c, O_RDWR) failed: Read-only file system (30) in Unknown on line 0




I panic, this is an emergency i thought. i thought maybe i got hacked into. maybe who knows.. but searched the internet and it turns out that there is a bug in php. that's weird, i've had several servers with apache and never come acrross this error. the worst thing came to mind was that i've lost all my data.

here it describes the bug:
http://bugs.php.net/bug.php?id=40068

So now what? well, my only option at this point was to reboot the server, so i logged into remotely to my server. when i logged in, i sent the reboot command in the shell, then i got this error:

CODE:
[root@host ~]# reboot
-bash: /sbin/reboot: Input/output error


oh, oh!!!, now what.. well, i still needed to have this server rebooted, i called www.webune support and they remotely power cycled the server, momments later, i was able to ping, then i logged in back again, a voala!, i was able to login, then i went to my site and there it was.

so to fix this problem (not sure if i fixed it) all i had to do was to power cycled the server. hopefuly i will never see this mysqsl errro again

Thanks to the guys at www.webune.com for their support on this.

UPDATE: it happened again. after troubleshooting, we found out that there was a bad hard drive. since we had RAID 5 on this server, we could do a hot swap on it and did not loose any data. so if you get this error, it might be a good idea to check your hardware.