SAP Software Changes

If the package still runs, all monitors will begin to work immediately and the package failover mechanism is restored.

During installation of the SGeSAP Integration for SAP releases with kernel <7.0, SAP profiles are changed to contain only relocatable IP-addresses for the database as well as the Central Instance. You can check this using transaction RZ10. In the DEFAULT.PFL these entries are altered:

SAPDBHOST= <relocatible_db_name> rdisp/mshost= <relocatible_ci_name> rdisp/vbname= <relocatible_ci_name>_<SID>_<INR> rdisp/enqname= <relocatible_ci_name>_<SID>_<INR> rdisp/btcname= <relocatible_ci_name>_<SID>_<INR> rslg/collect_daemon/host = <relocatible_ci_name>

There are also two additional profile parameters SAPLOCALHOST and SAPLOCALHOSTFULL included as part of the Instance Profile of the Central Instance. Anywhere SAP uses the local hostname internally, this name is replaced by the relocatable values <relocatable_ci_name> or <relocatable_ci_name>.domain.organization of these parameters. Make sure that they are always defined and set to the correct value. This is vital for the system to function correctly.

Relocatable IP addresses can be used consistently beginning with SAP kernel 6.40. Older releases use local hostnames in profile names and startup script names. Renamed copies of the files or symbolic links exist to overcome this issue.

The destination for print formatting, which is done by a Spool Work process, uses the Application Server name. Use the relocatable name if you plan to use Spool Work processes with your Central Instance. In these cases no changes need to be done in case of a failover - printing will work persistently.

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.

Within the CCMS you can define operation modes for SAP instances. An operation mode defines a resource configuration. It can be used to determine which instances are started and stopped and how the individual services are allocated for each instance in the configuration. An instance definition for a particular operation mode consists of the number and types of Work processes as well as Start and Instance Profiles. When defining an instance for an operation mode you need to enter the hostname and the system number of the application server. By using relocatable names to fill in the hostname field, the instance will be working under control of the CCMS after a failover without a change.

Change Management 139