Using Serviceguard Extension for RAC, 10th Edition, April 2013

Selecting Disks for the Volume Group
Obtain a list of the disks on both nodes and identify which device files are used for the same disk
on both. Use the following command on each node to list available disks as they are known to
each system:
# lssf /dev/dsk/*
In the following examples, we use /dev/rdsk/c1t2d0 and /dev/rdsk/c0t2d0, which are
the device names for the same disks on both ftsys9 and ftsys10. In the event that the device
file names are different on the different nodes, make a careful note of the correspondences.
Creating Physical Volumes
On the configuration node (ftsys9), use the pvcreate command to define disks as physical
volumes. This only needs to be done on the configuration node. Use the following commands to
create two physical volumes for the sample configuration:
# pvcreate -f /dev/rdsk/c1t2d0
# pvcreate -f /dev/rdsk/c0t2d0
Creating a Volume Group with PVG-Strict Mirroring
Use the following steps to build a volume group on the configuration node (ftsys9). Later, the
same volume group will be created on other nodes.
1. Set up the group directory for vgops:
# mkdir /dev/vg_rac
2. Create a control file named group in the directory /dev/vg_rac, as follows:
# mknod /dev/vg_rac/group c 64 0xhh0000
The major number is always 64, and the hexadecimal minor number has the form
0xhh0000
where hh must be unique to the volume group you are creating. Use the next hexadecimal
number that is available on your system, after the volume groups that are already configured.
Use the following command to display a list of existing volume groups:
# ls -l /dev/*/group
3. Create the volume group and add physical volumes to it with the following commands:
# vgcreate -g bus0 /dev/vg_rac /dev/dsk/c1t2d0
# vgextend -g bus1 /dev/vg_rac /dev/dsk/c0t2d0
The first command creates the volume group and adds a physical volume to it in a physical
volume group called bus0. The second command adds the second drive to the volume group,
locating it in a different physical volume group named bus1. The use of physical volume
groups allows the use of PVG-strict mirroring of disks and PV links.
4. Repeat this procedure for additional volume groups.
Building Mirrored Logical Volumes for RAC with LVM Commands
After you create volume groups and define physical volumes for use in them, you define mirrored
logical volumes for data, logs, and control files. It is recommended that you use a shell script to
issue the commands described in the next sections. The commands you use for creating logical
volumes vary slightly depending on whether you are creating logical volumes for RAC redo log
files or for use with Oracle data.
Creating Mirrored Logical Volumes for RAC Redo Logs and Control Files
Create logical volumes for use as redo log and control files by selecting mirror consistency recovery.
Use the same options as in the following example:
Creating a Storage Infrastructure with LVM 43