NFS client not able to gain locks on file.

Issue

• Without the nolock option, databases hosted on NFS share do not start anymore or are operating slowly.

• Using strace on processes shows the software cannot process a lock :

  stat("/method/meth/mnt/data/db/meth/.lock", {st_mode=S_IFREG|0600, st_size=44, ...}) = 0
  open("/method/meth/mnt/data/db/meth/.lock", O_RDWR) = 6
  fcntl(6, F_SETLKW, {type=F_WRLCK, whence=SEEK_CUR, start=0, len=1}
  

• We see several NLM_BLOCK and NLM_DENIED in network captures.