Managing Serviceguard Extension for SAP, December 2007

SGeSAP Cluster Administration
Change Management
Chapter 6302
NOTE A print job in process at the time of the failure will be canceled and needs
to be reissued manually after the failover. To make a spooler highly
available on the Central Instance, set the destination of the printer to
<relocatible_ci_name>_<SID>_<nr> using the transaction SPAD. Print
all time critical documents via the high available spool server of the
Central Instance.
Print requests to other spool servers stay in the system after failure until
the host is available again and the spool server has been restarted. These
requests can be moved manually to other spool servers if the failed
server is unavailable for a longer period of time.
Batch jobs can be scheduled to run on a particular instance. Generally
speaking, it is better not to specify a destination host at all. Sticking to
this rule, the batch scheduler chooses a batch server which is available at
the start time of the batch job. However, if you want to specify a
destination host, specify the batch server running on the highly available
Central Instance. The application server name and the hostname (which
is retrieved from the Message Server) are stored in the batch control
tables TBTCO, TBTCS,.... In case the batch job is ready to run, the
application server name is used to start it. Therefor, when using the
relocatable name to build the Application Server name for the instance,
you do not need to change batch jobs which are tied to it after a
switchover. This is true even if the hostname which is also stored in the
above tables, differs.
Plan to use saplogon to application server groups instead of
saptemu/sapgui to individual application servers. When logging on to
an application server group with two or more application servers, the
SAP user does not need a different login procedure if one of the
application servers of the group fails. Also, using login groups, provides
workload balancing between application servers, too.