The discussion of distributed filesystems inspired me to start a new thread on NFS. Like probably everyone on this list, we use NFS to share files (home directories, whatever) among machines. It pretty much works ok... except for the occasional problem which appears to be related to NFS. Does anyone else have low level NFS problems, or am I the only one? In more detail, here's the kind of thing I've seen. We use NIS to distribute autofs configuration files, so everyone gets the same configuration, and then the automounter mounts the necessary disks from a fileserver. Our machines are mostly SL 3.0.2; we're about to upgrade to 3.0.5 (I'd rather 4.2, but we want to be consistent with the much larger computer center down the street). For quite a few years, the NFS fileserver was just another one of our machines; last summer, I thought it would be nice to upgrade to something more appliance-like, and so I bought quite a nice Linux based RAID NAS device that runs Linux from flash memory, has redundant power supplies etc. Everything works reasonably well together, in a cluster of around 100 machines. However, some machines, when they are running jobs and under heavy load, become unresponsive. It can take a few days or a week, but you basically can't prevent it. We think this is because of an NFS mounted volume in the PATH. If you get in as root, you can ping the server, rpcinfo the server, even mount other volumes on the server. Everything seems ok, until you cd to the wrong NFS mounted directory, then you're hung until you push the button. Getting back to the server, part of the reason we went to a commercial server was that we saw similar, or in some cases worse behavior, with our own server. I used to think it was a network problem because of messages like this scattered around various consoles: > messages.3:Nov 26 14:28:22 phnxbox0 kernel: nfs: server phnxsb0.phenix.bnl.gov not responding, still trying > messages.3:Nov 26 14:28:22 phnxbox0 kernel: nfs: server phnxsb0.phenix.bnl.gov OK but now I'm not so sure. Through it all, the server (ours or the store-bought one) thinks everything is going well. So I think there is some problem with the NFS clients, or maybe there is some incompatibility with the server. Or is there a magic configuration that works better? The arguments to the automounter look like this: > -nfsvers=3,hard,wsize=32768,rsize=32768 phnxsb0.phenix.bnl.gov:/share/software -- John Haggerty email: [log in to unmask] voice/fax: 631 344 2286/4592 http://www.phenix.bnl.gov/~haggerty