Using the four-system complex shown earlier in Figure 1, assume that it is necessary to stop SYS4 temporarily.

On SYS4, the operator would take the following steps:

1. Bring the work to an orderly shutdown by taking such actions as stopping the subsystems and terminating jobs.
2. Issue VARY GRS(*),QUIESCE or VARY GRS(SYS4),QUIESCE. (An operator on any active system could also issue the second command.)
   On SYS4, the following message appears:

   ISG012I QUIESCE REQUEST PASSED TO SYSTEM SYS2

   • This message indicates that global resource serialization has accepted the command and that SYS2 will assist in the quiesce process. SYS2 is the assisting system, and SYS4 is the target system. (This message appears only when the operator on the target system issues the VARY command.)
   On SYS2 and SYS4, the following message indicates that global resource serialization has started to quiesce the target system (SYS4):

   ISG011I SYSTEM SYS4 - QUIESCING GLOBAL RESOURCE SERIALIZATION

   On all systems, the following message appears after the system has been successfully quiesced.

   ISG013I SYSTEM SYS4 - QUIESCED GLOBAL RESOURCE SERIALIZATION

3. Once the quiesce is successful, the operator on SYS4 can stop the system.

Issuing D GRS would show the state of SYS4 as QUIESCED. The COMM field would show YES, indicating that communication still existed, and all links to SYS4 would appear as ALTERNATE.