The ERS instance is running on both the primary and backup servers at the same time.
If the ERS instance profile is configured to start the instance with Restart_Program instead of Start_Program, the sapstart process will automatically restart the ERS instance when it is terminated for any reason. This will cause unexpected behavior and could lead to a loss of the enqueue server lock table during failover or switchover.
Identify the location of the active ERS instance profile. This can be found from the /usr/sap/sapservices file by looking at the line:
LD_LIBRARY_PATH=/usr/sap/STC/ERS10/exe:$LD_LIBRARY_PATH; export LD_LIBRARY_PATH; /usr/sap/STC/ERS10/exe/sapstartsrv pf=/usr/sap/STC/ERS10/profile/STC_ERS10_sap2 -D -u stcadm
In this example, the active ERS instance profile is located at /usr/sap/STC/ERS10/profile/STC_ERS10_sap2.
Edit the ERS profile and replace the line
Restart_Program_00 = local $(_ER) pf=$(_PFL) NR=$(SCSID)
Start_Program_00 = local $(_ER) pf=$(_PFL) NR=$(SCSID)
Note that the number 00 may be different in your instance profile.
In order for the change to take effect, restart the sapstartsrv process corresponding to the ERS instance with the command:
su – <sid>adm -c “sapcontrol -nr <ERS Inst#> -function RestartService <SID>”
Now stop the ERS instance on the system(s) where it should not be running by using the command:
su – <sid>adm -c “sapcontrol -nr <ERS Inst#> -function Stop”
on those systems. The ERS instance should only be running on the backup system where the ASCS/SCS instance is not currently running.