PRIMECLUSTER Global File Services Configuration and Administration Guide 4.2 (Solaris(TM) Operating Environment)

22.8.2 Changing the MDS operational information

In the GFS Shared File System, information about all nodes that operate MDS is retained.

• Whether MDS placement on all nodes is set
• Number of nodes on which MDS is placed
• Priority of nodes on which to place MDS as primary or secondary MDS

Use sfcadm(1M) to change information about nodes on which MDS is placed.

For details on sfcadm(1M) options, see Appendix F.2.2, "sfcadm(1M)."

The following shows how to change information about nodes on which MDS is placed using sfcadm(1M).

22.8.2.1 Enabling MDS placement on all nodes

1. Check the current file system configuration. Two nodes (mikan and karin) are currently in the MDS placement range.

# sfcinfo -n /dev/sfdsk/gfs/dsk/volume1
/dev/sfdsk/gfs/dsk/volume1:
FSID  hostID    status  hostname
   1  80807658  STOP    mikan
   1  807e7937  STOP    karin
   1  80804266  STOP    mango
   1  80b6324a  STOP    ringo

# sfcinfo -c /dev/sfdsk/gfs/dsk/volume1
/dev/sfdsk/gfs/dsk/volume1:
node=mikan,karin

2. Change the MDS placement range to all shared hosts.

# sfcadm -c all /dev/sfdsk/gfs/rdsk/volume1

3. Confirm that the MDS placement range has been changed. "all" is now displayed to confirm that the MDS placement range includes all nodes.

# sfcinfo -c /dev/sfdsk/gfs/dsk/volume1
/dev/sfdsk/gfs/dsk/volume1:
node=mikan,karin,mango,ringo
mdsnode=all

If all nodes are set in the MDS placement range, an added node is automatically integrated into the range when a shared node is subsequently added using sfcnode(1M).

22.8.2.2 Changing the MDS placement range

Specify the MDS placement range using the number of nodes from the first node in the shared host list specified at file system creation.

1. Check the current file system configuration. "all" is currently displayed to confirm that the MDS placement range includes all nodes.

# sfcinfo -n /dev/sfdsk/gfs/dsk/volume1
/dev/sfdsk/gfs/dsk/volume1:
FSID  hostID    status  hostname
   1  80807658  STOP    mikan
   1  807e7937  STOP    karin
   1  80804266  STOP    mango
   1  80b6324a  STOP    ringo

# sfcinfo -c /dev/sfdsk/gfs/dsk/volume1
/dev/sfdsk/gfs/dsk/volume1:
node=mikan,karin,mango,ringo
mdsnode=all

2. Change the MDS placement range from all nodes to three nodes (mikan, karin, and mango).

# sfcadm -c 3 /dev/sfdsk/gfs/rdsk/volume1

3. Confirm that the MDS placement range has been changed.

# sfcinfo -c /dev/sfdsk/gfs/dsk/volume1
/dev/sfdsk/gfs/dsk/volume1:
node=mikan,karin,mango

22.8.2.3 Changing the MDS placement priority

1. Check the current file system configuration.

# sfcinfo -n /dev/sfdsk/gfs/dsk/volume1
/dev/sfdsk/gfs/dsk/volume1:
FSID  hostID    status  hostname
   1  80807658  STOP    mikan
   1  807e7937  STOP    karin
   1  80804266  STOP    mango
   1  80b6324a  STOP    ringo

# sfcinfo -c /dev/sfdsk/gfs/dsk/volume1
/dev/sfdsk/gfs/dsk/volume1:
node=mikan,karin,mango

2. Change the priorities of nodes on which MDS is placed.

# sfcadm -g mango,ringo,mikan /dev/sfdsk/gfs/dsk/volume1

3. Confirm that the MDS placement range has been changed.

# sfcinfo -c /dev/sfdsk/gfs/dsk/volume1
/dev/sfdsk/gfs/dsk/volume1:
node=mango,ringo,mikan