This topic describes how to modify existing enhanced multiple reader
configurations to use alias addresses instead of unique volumes, or
use volumes instead of alias addresses. To use alias addresses, set
the NumberReaderTasks parameter to be a nonzero value. The following
scenarios direct how to modify the configurations. The NumbeerReaderTasks
value is set to four in all the configurations.
- Configuration one: All independent base volumes, no aliases.
The volumes are UTL001, UTL002, UTL003, UTL004.
- Configuration two: Two base volumes, each with one alias (or two
shared HyperAV aliases). The volumes are UTL001, UTL002.
- Configuration three: One base volume and three aliases. The volume
is UTL001.
To modify configuration two and three to configuration
one for using base volumes instead of utility volumes, do the following:
- Issue an XADDPAIR command to add extra base utility volumes. XRC
will use these new utility volumes instead of using alias devices.
Message ANTA8171I is issued to reflect that the readers have been
re-balanced.
- Issue XSUSPEND VOLUME(ALL) to suspend all the volumes in the session.
- Set the NumberReaderTasks value to zero to prevent the use of
alias addresses when the base address is busy.
- Issue XSET PARMLIB to activate the NumberReadrTasks value of zero.
This automatically re-adds the base utility or utilities and deletes
all of the alias utilities.
- Issue XADDPAIR SUSPENDED to resume XRC mirroring.
To modify configuration one to configuration two or three for using
alias addresses, do the following:
- Configure alias addresses.
- Set the NumberReaderTasks value to four.
- Issue an XDELPAIR command to delete the extraneous utility volumes.
To modify configuration two to configuration three for continuing
the use of alias addresses, do the following:
- Ensure the UTL001 volume has at least three alias addresses.
- Issue an XDELPAIR command to delete the UTL002 volume.
To change the configuration three to the configuration two for
adding a base address, do the following:
- Ensure UTL002 has at least one alias.
- Issue an XADDPAIR command against UTL002.
- Decrease the number of aliases for UTL001.