Using Serviceguard Extension for RAC, 8th Edition, March 2009

5. Activate the volume group on one node in exclusive mode then deactivate the volume group:
# vgchange -a e vg_ops
This will synchronize the stale logical volume mirrors. This step can be time-consuming,
depending on hardware characteristics and the amount of data.
6. Deactivate the volume group:
# vgchange -a n vg_ops
7. Activate the volume group on all the nodes in shared mode using vgchange - a s:
# vgchange -a s vg_ops
Replacing a Lock Disk
Replacing a failed lock disk mechanism is the same as replacing a data disk. If you are using a
dedicated lock disk (one with no user data on it), then you need to issue only one LVM command:
# vgcfgrestore /dev/vg_lock /dev/dsk/c2t1d0
After doing this, wait at least an hour, then review the syslog file for a message showing that the
lock disk is healthy again.
On-line Hardware Maintenance with In-line SCSI Terminator
Serviceguard allows on-line SCSI disk controller hardware repairs to all cluster nodes if you use
HP’s in-line terminator (C2980A) on nodes connected to the end of the shared FW/SCSI bus. The
in-line terminator cable is a 0.5 meter extension cable with the terminator on the male end, which
connects to the controller card for an external bus. The in-line terminator is used instead of the
termination pack that is attached to the controller card and makes it possible to physically
disconnect the node from the end of the F/W SCSI bus without breaking the bus's termination.
(Nodes attached to the middle of a bus using a Y cable also can be detached from the bus without
harm.) When using in-line terminators and Y cables, ensure that all orange-socketed termination
packs are removed from the controller cards.
NOTE: You cannot use inline terminators with internal FW/SCSI buses on D and K series
systems, and you cannot use the inline terminator with single-ended SCSI buses. You must not
use an inline terminator to connect a node to a Y cable.
Figure 4-1 shows a three-node cluster with two F/W SCSI buses. The solid line and the dotted
line represent different buses, both of which have inline terminators attached to nodes 1 and 3.
Y cables are also shown attached to node 2.
130 Maintenance and Troubleshooting