ServerNet Cluster Manual

Adding or Removing a Node
ServerNet Cluster Manual—520575-003
6-12
Splitting a Large Cluster Into Multiple Smaller
Clusters
3. In all nodes of the star group selected in Step 1:
a. Stop any applications that depend on ServerNet cluster connectivity to nodes
in the other star group(s).
b. Stop Expand connectivity to the nodes in the other star group(s):
1. Use the Expand subsystem SCF LISTDEV command to identify the
currently configured Expand-over-ServerNet lines:
-> LISTDEV TYPE 63,4
2. Use the Expand subsystem SCF ABORT LINE command to abort the
Expand-over-ServerNet lines to the nodes in other star group(s):
-> ABORT LINE $SCxxx
3. Use the WAN subsystem SCF STOP DEVICE command to stop the line-
handler process associated with each Expand-over-ServerNet line you
aborted.
-> STOP DEVICE $ZZWAN.#SCxxx
4. Use the WAN subsystem DELETE DEVICE command to delete the line-
handler process associated with each Expand-over-ServerNet line you
aborted.
-> DELETE DEVICE $ZZWAN.#SCxxx
c. Use the SCF STOP SUBSYS $ZZSCL command to ensure an orderly
shutdown of ServerNet communications:
-> STOP SUBSYS $ZZSCL
4. In all nodes of the other star groups, abort all Expand-over-ServerNet lines to the
nodes in the star group selected in Step 1.
-> ABORT LINE $SCxxx
5. On both fabrics, disconnect the four-lane links (or two-lane links) between the star
group selected in Step 1 and the other star group(s). (The four-lane links or two-
lane links are the switch-to-switch cables connected to ports 8 through 11.)
Caution. To avoid generating an alarm, you must disconnect the four-lane or two-lane links on
both fabrics within four minutes if the ServerNet II Switches are running T0569AAB (eight
minutes if the switches are running T0569AAE). The TSM incident analysis (IA) software
generates an alarm eventually if one external fabric has a different number of cluster switches
than the other external fabric.