sharing PHP sessions between web servers using NFS

[Randy Paries <rtparies@xxxxxxxxx>]

Hello,
I have three web servers (in a lvs cluster)
in the cluster they all think they are www.mydomain.com
With LVS you can not guarantee that each request is going to come in
via the same server

I am trying to share php sessions between servers.

I have seen some examples that use mysql for session, but i think this may work
and would be easier to implement

currently all three servers share the same file system via NFS

so what i was going to do is change the path in the php.ini to
session.save_path = "/mynfsmount/phpsessions". So essentially all
three servers would write the session files in the same location.

my concern is does anyone know how php creates the session ID
the thing that concerns me is that i compared the current session
directories on the 3 servers and there are duplicate file names. Do
you think i can assume that PHP checks for the existence of the
session file before it creates a new PHPSESSIONID??

the one thing that would be ugly is if the servers overwrote the
others files and sessions started getting messed up.

Thanks for your help