Checking major and minor numbers for disk partitions


Checking major and minor numbers for disk partitions
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The following sections describe checking and changing, if necessary, the major and minor numbers for disk partitions used by cluster nodes.

To check major and minor numbers on disk partitions

Use the following command on all nodes exporting an NFS file system. This command displays the major and minor numbers for the block device.
```
# ls -lL block_device
```
The variable block_device refers to a partition where a file system is mounted for export by NFS. Use this command on each NFS file system. For example, type:
```
# ls -lL /dev/dsk/c1t1d0s2
```
Output on Node A resembles:
```
crw-r-----  1 root  sys  32,1 Dec 3 11:50 /dev/dsk/c1t1d0s2
```
Output on Node B resembles:
```
crw-r-----  1 root  sys  32,1 Dec 3 11:55 /dev/dsk/c1t1d0s2
```
Note that the major numbers (32) and the minor numbers (1) match, satisfactorily meeting the requirement for NFS file systems.

To reconcile the major numbers that do not match on disk partitions

Reconcile the major and minor numbers, if required. For example, if the output in the previous section resembles the following, perform the instructions beginning step 2:
Output on Node A:
```
crw-r-----  1 root  sys  32,1 Dec 3 11:50 /dev/dsk/c1t1d0s2
```
Output on Node B:
```
crw-r-----  1 root  sys  36,1 Dec 3 11:55 /dev/dsk/c1t1d0s2
```

Place the VCS command directory in your path.

# export PATH=$PATH:/usr/sbin:/sbin:/opt/VRTS/bin

Attempt to change the major number on System B (now 36) to match that of System A (32). Use the command:
```
# haremajor -sd major_number
```
For example, on Node B, enter:
```
# haremajor -sd 32
```
If the command succeeds, go to step 8.

If the command fails, you may see a message resembling:

    Error: Preexisting major number 32
    These are available numbers on this system: 128...
    Check /etc/name_to_major on all systems for
    available numbers.

Notice that the number 36 (the major number on Node A) is not available on Node B. Run the haremajor command on Node B and change it to 128,
```
# haremajor -sd 128
```
Run the same command on Node A. If the command fails on Node A, the output lists the available numbers. Rerun the command on both nodes, setting the major number to one available to both.
Reboot each system on which the command succeeds.
Proceed to reconcile the major numbers for your next partition.

To reconcile the minor numbers that do not match on disk partitions

In the example, the minor numbers are 1 and 3 and are reconciled by setting to 30 on each node.
Type the following command on both nodes using the name of the block device:
```
# ls -1 /dev/dsk/c1t1d0s2
```
Output from this command resembles the following on Node A:
```
    lrwxrwxrwx  1 root  root  83 Dec 3 11:50 
     /dev/dsk/c1t1d0s2         -> ../../ 
     devices/sbus@1f,0/QLGC,isp@0,10000/sd@1,0:d,raw
```
The device name (in bold) includes the slash following the word devices, and continues to, but does not include, the colon.

Type the following command on both nodes to determine the instance numbers that the SCSI driver uses:

# grep sd /etc/path_to_inst | sort -n -k 2,2

Output from this command resembles the following on Node A:

    "/sbus@1f,0/QLGC,isp@0,10000/sd@0,0" 0 "sd"
    "/sbus@1f,0/QLGC,isp@0,10000/sd@1,0" 1 "sd"
    "/sbus@1f,0/QLGC,isp@0,10000/sd@2,0" 2 "sd"
    "/sbus@1f,0/QLGC,isp@0,10000/sd@3,0" 3 "sd"
    .
    .
    "/sbus@1f,0/SUNW,fas@e,8800000/sd@d,0" 27 "sd"
    "/sbus@1f,0/SUNW,fas@e,8800000/sd@e,0" 28 "sd"
    "/sbus@1f,0/SUNW,fas@e,8800000/sd@f,0" 29 "sd"

In the output, the instance numbers are in the second field.

The instance number that is associated with the device name that matches the name for Node A displayed in step 2, is "1."

Compare instance numbers for the device in the output on each node.
After you review the instance numbers, perform one of the following tasks:
- If the instance number from one node is unused on the other - it does not appear in the output of step 3 - edit /etc/path_to_inst.
  
  You edit this file to make the second node's instance number similar to the number of the first node.
- If the instance numbers in use on both nodes, edit /etc/path_to_inst on both nodes. Change the instance number that is associated with the device name to an unused number. The number needs to be greater than the highest number that other devices use. For example, the output of step 3 shows the instance numbers that all devices use (from 0 to 29). You edit the file /etc/path_to_inst on each node and reset the instance numbers to 30.
Type the following command to reboot each node on which /etc/path_to_inst was modified:
```
# reboot -- -rv
```