Managing Serviceguard Sixteenth Edition, March 2009

Online Hardware Maintenance with In-line SCSI Terminator
In some shared SCSI bus configurations, online SCSI disk controller hardware repairs
can be made if HP in-line terminator (ILT) cables are used. In-line terminator cables
are supported with most SCSI-2 Fast-Wide configurations.
In-line terminator cables are supported with Ultra2 SCSI host bus adapters only when
used with the SC10 disk enclosure. This is because the SC10 operates at slower SCSI
bus speeds, which are safe for the use of ILT cables. In-line terminator cables are not
supported for use in any Ultra160 or Ultra3 SCSI configuration, since the higher SCSI
bus speeds can cause silent data corruption when the ILT cables are used.
Replacing I/O Cards
Replacing SCSI Host Bus Adapters
After a SCSI Host Bus Adapter (HBA) card failure, you can replace the card using the
following steps.
Normally disconnecting any portion of the SCSI bus will leave the SCSI bus in an
unterminated state, which will cause I/O errors for other nodes connected to that SCSI
bus, so the cluster would need to be halted before disconnecting any portion of the
SCSI bus. However, it is not necessary to bring the cluster down to do this if you are
using a SCSI configuration that allows disconnection of a portion of the SCSI bus
without losing termination.
SCSI bus configurations using SCSI in-line terminators or Y cables at each node, or
using a SCSI device which auto-terminates its ports when disconnected (such as the
MSA30 MI), can allow online repair.
1. Halt the node. You can use Serviceguard Manager to do this, or use the
cmhaltnode command. Packages should fail over normally to other nodes.
2. Remove the SCSI cable from the card.
3. Remove the defective SCSI card.
4. Install the new SCSI card. The new card must be exactly the same card type, and
it must be installed in the same slot as the card you removed. You must set the
SCSI ID for the new card to be the same as the card it is replacing.
5. Attach the new SCSI card.
6. Add the node back into the cluster. You can use Serviceguard Manager to do this,
or use the cmrunnode command.
Replacing LAN or Fibre Channel Cards
If a LAN or fibre channel card fails and the card has to be replaced, you can replace it
online or offline depending on the type of hardware and operating system you are
running. It is not necessary to bring the cluster down to do this.
368 Troubleshooting Your Cluster