On Thu, Mar 29, 2007 at 08:52:18PM +0200, Christos Triantafillou wrote: > Hello, > > I am using a RHEL4 cluster with 2 nodes, GFS and fencing. > > As a test, I started a process on node2 that got an fcntl() exclusive lock > on a GFS file > and then a process on node1 that started the same program waiting for an > exclusive > lock on the same GFS file. > Node2 was then switched off and rebooted. > > What I observed was that node1 did not acquire the lock immediately after > the switch-off but only when node2 finished rebooting. > > A few questions: > 1. when a node goes down, shouldn't all its GFS locks be (almost) > immediately released as part of the fencing proces or the GFS recovery on > the other nodes? Yes. Did the remaining node have quorum when you killed the other? If not, then you should set two_node=1 in cluster.conf so it will. Fencing, dlm recovery and gfs recovery won't happen unless there's quorum; after this recovery, the locks you want should be granted (regardless of whether the other node has rebooted or not). > 2. during the lock wait, it was impossible to interrupt/kill the process on > node1. Is it possible to interrupt a process waiting on a POSIX lock? no > 3. if the previous are not possible, would it be preferable to use POSIX > locks on an NFS file instead? > Or would you recommend using DLM? Either, possibly; you'd have to try it out. GFS works much better with flock (although that's not interruptible either), if that's an option. Dave -- Linux-cluster mailing list Linux-cluster@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/linux-cluster
