HP-UX HB v13.00 Ch-15 - Serviceguard

HP-UX Handbook – Rev 13.00 Page 27 (of 108)

Chapter 15 Serviceguard

October 29, 2013

# cmquerycl

Cluster Name Node Name

UNUSED

rxh17u07

rxh17u09_cluster

rxh17u09

LVM preparation

When a volume group is created, /etc/lvmtab (or for version 2.X volume groups, /etc/lvmtab_p)

is loaded with references to the volume group and related physical devices. Every node that will

run a package must have an lvmtab file that will allow activation of a package VG. After

creating a volume group on one node, import it into the other adoptive nodes. Note that unless

cDSFs are specified, the device special files representing a shared LUN may differ across

systems. Use this example (Node2 was where the vg was created) to update /etc/lvmtab* on

adoptive nodes:

1. On Node2, create a map files.

# for vg in `strings /etc/lvmtab | grep -v -E 'disk|dsk' | sed 's_/dev/__g'`

vgexport -pvs -m /etc/lvmconf/$vg.map /dev/$vg

done

2. Copy the map file to nodeC:

root@Node2:/ # rcp / etc/lvmconf/vgspare.map nodeC:/etc/lvmconf/vgspare.map

3. On nodeC, create the volume group directory:

root@nodeC:/ # mkdir /dev/vgspare

4. Still on nodeC create a control file named group in the directory /dev/vgspare, as follows:

root@nodeC:/ # mknod /dev/vgspare/group c 64 0xhh0000

hh: Use the same minor number as on Node2 as used on nodeC when possible. Use the

following command to display a list of used minor numbers:

root@nodeC:/ # ls -l /dev/*/group

5. Import the volume group data using the map file from node Node2. On node nodeC, enter:

root@nodeC:/ # vgimport -s -m /etc/lvmconf/vgspare.map /dev/vgspare

Note that the disk device names on nodeC may be different from their names on Node2. Make

sure the physical volume names are correct throughout the cluster. When the volume group can

be activated on this node, perform a vgcfgbackup. (This backup will be available in the unlikely

event that a vgcfgrestore must be performed on this node because of a disaster on the primary

node and an LVM problem with the volume group.) Do this as shown in the example below:

# vgchange -a y /dev/vgspare

# vgcfgbackup /dev/vgspare

# vgchange -a n /dev/vgspare

NOTE: When LVM mirroring is used, consider creating a /etc/lvmpvg file on each node to

ensure that each mirror is created on a different array, if the cluster has such a configuration.

Note that the lvmpvg on each node will contain different device special files if lvmtab differs

between nodes. See the SAW document titled “HPUX Serviceguard - Using /etc/lvmpvg

to put mirror data on different arrays”