ENOENT on first reference to an automounted file

[Dan Halbert <halbert@everyzing.com>]

I have what looks like an automount race condition, and am very puzzled. 
Any suggestions would be appreciated.

The first time I reference an automounted file, it is not there 
(ENOENT). On the second and later try, the file is there. For instance:

     $ cat /net/fileserver/fs/somefile
     cat: /net/fileserver/fs/somefile: No such file or directory
     $ cat /net/fileserver/fs/somefile
     Contents of somefile.

I watched the log on fileserver, and the automount request is logged 
seemingly immediately after the first "cat" prints its error.

This causes havoc with our applications, which expect files to be there 
the first time they look for them.

I can repeat the problem after umounting the fileystem.

I see this problem on a CentOS 4.x system running their standard 
autofs-4.1.3-199.3. I do NOT see it on CentOS 5.x, using 
autofs-5.0.1-0.rc2.43.0.2. Instead I see a slight pause before "cat" 
prints the contents of the file, presumably as the automount completes. 
Both the CentOS4 and CentOS5 systems are completely up-to-date.

I also only see this problem with our Linux NFS servers (FC5 and FC6), 
but not with a non-Fedora NAS server we have.

So I am not sure this is an automount problem, per se. Perhaps it's some 
kind of NFS version problem?

The automount options include --ghost. At first I thought it might be 
due to --ghost, because the very first time I reference the file, say 
after a reboot or restarting autofs, I don't get an ENOENT. The first 
time, the mountpoint dir does not yet exist. But removing --ghost from 
the automount options does not seem to fix it.

Gory details about the automount maps are below.

Thanks for any help,
Dan Halbert

---------------
More details:

Our automount maps are stored in ldap. The entry in auto.master for 
fileserver (for cn=/net/fileserver) is:

     ldap:ou=auto.fileserver,ou=autofs,dc=example,dc=com --timeout=86400 
--ghost -o 
rw,hard,async,noatime,intr,retrans=4,timeo=100,rsize=8192,wsize=8192


The auto.fileserver is (for cn=*):

     fileserver.example.com:/export/&

We are not using the fancy executable /net maps that come with these 
systems.