User can't write to /tmp

[Garrettj94]

I recently updated PHP to 5.5 on my server, and now it's causing a few problems. I have 2 WordPress sites with the same theme, and there is an issue with one of the plugins. Here is one of the PHP warnings:

Warning: session_start(): open(/tmp/sess...) failed: Permission denied (13) in /plugins/custom-sidebars/functions-wpmulib.php on line 69

In SSH, I entered "sudo chown -R USER /tmp" user being the ftp user for WP site 1. This fixed the issue for WP site 1, and when I try to do the command for WP site 2, it fixes it and breaks WP site 1 again. I have no clue what to do now.

Edit: Also, the path for session.save_path is /tmp

 

[anton_latvia]

How do you have your PHP configured in Apache? Do both sites have the same unix user or different? Can you confirm there is enough space and enough free inodes in /tmp partition?

 

[Garrettj94]

How do you have your PHP configured in Apache? Do both sites have the same unix user or different? Can you confirm there is enough space and enough free inodes in /tmp partition?

"df /tmp": Filesystem 1K-blocks Used Available Use% Mounted on

/usr/tmpDSK 4128448 139872 3778864 4% /tmp​

"df -i":
Filesystem Inodes IUsed IFree IUse% Mounted on
/dev/sda3 17752064 253839 17498225 2% /
tmpfs 986006 1 986005 1% /dev/shm
/dev/sda1 65536 45 65491 1% /boot
/usr/tmpDSK 262144 883 261261 1% /tmp

And not sure how to check if both sites are sharing same user...

 

[Garrettj94]

Could it be a cache issue? It's not showing the errors in Firefox...

 

[anton_latvia]

Does these 2 sites each have their own cpanel user or the same?
You should not run "sudo chown -R USER /tmp". as this changes owner for /tmp itself.
Try fixing /tmp with:

chown root.root /tmp
chmod 777 /tmp
​

then try cleaning all session data (well, if that is safe)

find /tmp -name sess\* -type f -exec rm -f {} \;​

Not sure why browsers shown/don't show errors, that should not be the case, since those errors are generated on server. Try cleaning session data first..

 

[Infopro]

Is that plugin up to date? Lots of results searching google for:
"functions-wpmulib.php on line 69"