NOTE:
Dual-host capability for VAX 4000 Model 200 systems is only
supported under VMS (Version 5.4 and later) when the two systems are
configured into the same VAXcluster.
The benefits of a dual-host configuration are:
•
VAXcluster features such as shared data across systems and satellite
nodes.
•
Higher system availability—If one of the DSSI-based systems is
unavailable, for example, due to a system malfunction, the satellites
booted through it are able to continue operating through the other
system.
If one of the DSSI-based systems fails, all satellite nodes booted through
that system lose connections to the system disk. Each satellite node knows,
however, that the system disk is also available through a second path. The
satellite nodes establish a new connection through the other system and
continue operation.
To increase system availability, a second system disk may be added to each
boot node. In the event of one system disk failure, the remaining system
disk would continue to serve one DSSI-based system and the satellite nodes
booted through it. As with any VAXcluster, however, a second system disk
improves availability while increasing system management tasks.
1–26
VAX 4000 Model 200 (BA430) Operation
