Using Serviceguard Extension for RAC, 9th Edition, September 2010

Figure 4-1 F/W SCSI Buses with Inline Terminators
The use of inline SCSI terminators allows you to do hardware maintenance on a given node by
temporarily moving its packages to another node and then halting the original node while its
hardware is serviced. Following the replacement, the packages can be moved back to the original
node.
Use the following procedure to disconnect a node that is attached to the bus with an inline SCSI
terminator or with a Y cable:
1. Move any packages on the node that requires maintenance to a different node.
2. Halt the node that requires maintenance. The cluster will reform, and activity will continue
on other nodes. Packages on the halted node will switch to other available nodes if they are
configured to switch.
3. Disconnect the power to the node.
4. Disconnect the node from the inline terminator cable or Y cable if necessary. The other nodes
accessing the bus will encounter no problems as long as the inline terminator or Y cable
remains connected to the bus.
5. Replace or upgrade hardware on the node, as needed.
6. Reconnect the node to the inline terminator cable or Y cable if necessary.
7. Reconnect power and reboot the node. If AUTOSTART_CMCLD is set to 1 in the /etc/
rc.config.d/cmcluster file, the node will rejoin the cluster.
8. If necessary, move packages back to the node from their alternate locations and restart them.
Replacement of I/O Cards
After an I/O card failure, you can replace the card using the following steps. It is not necessary
to bring the cluster down to do this if you are using SCSI inline terminators or Y cables at each
node.
1. Halt the node by using Serviceguard Manager or the cmhaltnode command. Packages
should fail over normally to other nodes.
2. Remove the I/O cable from the card. With SCSI inline terminators, this can be done without
affecting the disks or other nodes on the bus.
3. Using SAM, select the option to do an online replacement of an I/O card.
Replacement of I/O Cards 127