ServerNet Nomadic Disk User's Guide

Switchovers
ServerNet Nomadic Disk User’s Guide—425485-001
5-5
Planned Switchovers
Planned Switchovers
You perform a planned switchover to continue operations on the backup node when the
primary node must be halted to perform significant maintenance tasks or software
upgrades, minimizing down time for the users of the primary node.
The following is an example of a planned switchover from primary node to backup
node.
On Primary node \PRI
1. Stop all running applications.
2. Change the position of the switches
•
If you are not using the Nomadic Disk Manager:
a. Use the SCF STOP DISK command to stop all ServerNet Nomadic Disk
drives.
b. Change the fiber-optic switches at the primary node to the opposite position
as described in Moving the Fiber Optic Switches to the Opposite Position
on
page 5-4.
•
If you are using the Nomadic Disk Manager:
a. Read Section 7, Nomadic Disk Manager Interface
.
b. Notify Network Services to perform the network switchover to the backup
node, \BCK.
c. Log on as the super ID and start the Nomadic Disk Manager at a TACL
prompt.
> NOMADIC
d. Use the LISTOPENS command to verify there are no open files on the
Nomadic volumes (except the SAFE.GUARD file on each volume, if
Safeguard is being used).
1 ND> LISTOPENS, SEGMENT *
e. Use the GIVE command to prepare for planned switchover.
2 ND> GIVE DATA
This command toggles the appropriate switch cards, switching the volumes
to \BCK.
3. Stop \PRI.
4. Inform the operators located at the \BCK node that the Nomadic volumes are ready
for switchover.