The following are some instructions we received from Ian Wells of HP
for setting the noac option on NFS. We have not tried them
ourselves. We are including them here because you may find 
them useful. Note that some of the steps may be specific to HP
systems, and you may need root permission to execute some of the
commands. 
   
   >1. first confirm you are running nfs version 3
   >
   >rpcnfo -p `hostname` | grep nfs
   >
   >ie 
   >    goedel >rpcinfo -p goedel | grep nfs
   >    100003    2   udp   2049  nfs
   >    100003    3   udp   2049  nfs
   >
   >
   >2. then edit /etc/fstab for each nfs directory read/written by MPIO
   >   on each  machine used for multihost MPIO.
   >
   >    Here is an example of a correct fstab entry for /epm1:
   >
   >   ie grep epm1 /etc/fstab
   > 
   >      ROOOOT 11>grep epm1 /etc/fstab
   >      gershwin:/epm1 /rmt/gershwin/epm1 nfs bg,intr,noac 0 0
   >
   >   if the noac option is not present, add it 
   >   and then remount this directory
   >   on each of the machines that will be used to share MPIO files
   >
   >ie
   >
   >ROOOOT >umount /rmt/gershwin/epm1
   >ROOOOT >mount  /rmt/gershwin/epm1
   >
   >3. Confirm that the directory is mounted noac:
   >
   >ROOOOT >grep gershwin /etc/mnttab 
   >gershwin:/epm1 /rmt/gershwin/epm1 nfs
   >noac,acregmin=0,acregmax=0,acdirmin=0,acdirmax=0 0 0 899911504