Stopping VCS in a standard environment

Stopping VCS in a standard environment

When you dynamically reconfigure CPU/Memory boards and I/O boards, it may be necessary, in some circumstances, to stop VCS in the domain.
Applications running on clusters of three or more domains remain highly available on two or more domains if VCS operation must be stopped on one domain. In a cluster of two domains, the applications running during reconfiguration are not highly available when VCS must be stopped on one of the domains.

To stop VCS in a standard environment

1. Log in as administrator to the domain (wildcat, for example) you are reconfiguring.
2. List the VCS service groups to determine which are online on the domain.
   # hagrp -list
3. If you can switch the service groups running on the domain to another domain (cheetah, for example), switch the service groups.
   # hagrp -switch service_grp_name -to cheetah
   Verify the service groups are offline on wildcat.
   # hastatus
   Stop VCS on wildcat.
   # hastop -local
4. If you cannot switch the online service groups to another system, freeze each of them for the duration of dynamic reconfiguration.
   Make the VCS configuration writable.
   # haconf -makerw
   Freeze each of the service groups persistently.
   # hagrp -freeze service_grp_name -persistent
   Verify the groups are frozen.
   # hagrp display | grep Frozen
   Make the configuration read-only.
   # haconf -dump -makero
   Stop VCS.
   # hastop -local -force
5. Unconfigure GAB.
   # /sbin/gabconfig -U
6. Unconfigure LLT.
   # /sbin/lltconfig -U
   Answer "y" to confirm that you want to stop LLT.
7. Remove the GAB and LLT modules from the kernel.
   Determine the IDs of the GAB and LLT modules:
   # modinfo | egrep "gab|llt"
   

   305 78531900 30e 305 1 gab
   292 78493850 30e 292 1 llt

   Unload the GAB and LLT modules based on their module IDs:
   # modunload -i 305
   # modunload -i 292
8. You can begin performing dynamic reconfiguration.