I've got many automount entries in LDAP for mounting ~200 nodes between each other. Often, the automounter stops working. After debugging, I figured out that it can be fixed by running
rm -f /etc/mtab~* restart autofs
which makes me think, that there are mount.nfs processes that somehow fail to remove the lock files (they are sometimes called /etc/mtab~.[0-9]*), which prevents the following mount requests to succeed. As a workaround I have a cron job removing the lock files, but it is sometimes too late.
Now the details:
System: Linux 2.6.32-33-server #70-Ubuntu SMP Thu Jul 7 22:28:30 UTC 2011 x86_64 GNU/Linux automount -V: 5.0.4 mount.nfs -V: linux nfs-utils 1.1.6
LDAP entries (relevant lines):
objectClass: automount cn: myhost automountInformation: -soft myhost:/var/tmp
a successful mount looks like this (mount | grep auto):
myhost:/var/tmp on /var/autofs/net/myhost type nfs (rw,soft,sloppy,addr=10.x.x.x)
whenever I access a new mountpoint, automounter spawns following processes (ps .. | grep mount)
/bin/mount -t nfs -s -o soft -f myhost:/var/tmp /var/autofs/net/myhost /sbin/mount.nfs myhost:/var/tmp /var/autofs/net/myhost -s -f -o rw,soft
if I try to run the command manually, I get following message:
Cannot create link /etc/mtab~ Perhaps there is a stale lock file?
Every following request to the automounter then fails.
My question now is how to make automounter behave correctly in the case of mount.nfs processes failing to remove the mtab~ lock file to allow all my hosts mount each other? Is it a matter of LDAP, NFS, automounter or mount.nfs options?
Please help me to get behind this problem!