Cluster Communications Control?
When there are multiple virtual circuits between two OpenVMS systems it is possible for the VMS$VAXCLUSTER to VMS$VAXCLUSTER connection to use any one of these circuits. All lock traffic between the two systems will then travel on the selected virtual circuit. Each port has a “LOAD CLASS” associated with it. This load class helps to determine which virtual circuit a connection will use. If one port has a higher load class than all others then this port will be used. If two or more ports have equally high load classes then the connection will use the first of these that it finds. Prior to enhancements found in V7.3-1 and later, the load class is static and normally all CI and DSSI ports have a load class of 14(hex), while the Ethernet and FDDI ports will have a load class of A(hex). With V7.3-1 and later, the load class values are dynamic. For instance, if you have multiple DSSI busses and an FDDI, the VMS$VAXCLUSTER connection will chose the DSSI bus as this path has the system disk, a
