September 20, 2009

SAP Basis Kernel Upgrade in Windows

Solution: Kernel upgrade change in SAP system

SAP note references:
19466 - Downloading SAP kernel patches

Below is generic practice:
Pre work - no SAP downtime required
Actual work - will require SAP system downtime due to kernel switch and some testing.
Post work - no downtime but SGEN background job will use simultaneous dialog process in load. Preferred to do this with less user is system.

1.0 Pre Work

1.1 Download the new kernel files. See Note 19466 - Downloading SAP kernel patches
1.2 Create a copy of I:\usr\sap\SAPSID\SYS\exe\ folder. Name it I:\usr\sap\SAPSID\SYS\exe_new
1.3 Extract new kernel CAR/SAR files to I:\usr\sap\SAPSID\SYS\exe_new, overwrite if necessary. Use SAPCAR -xvf

2.0 Actual work


2.1 Stop your SAP system
2.2 Stop your SAP services (e.g SAP,SAPOScol)

Perform kernel switch.

2.3 Go to your current SAP kernel folder I:\usr\sap\SAPSID\SYS\
2.4 Rename I:\usr\sap\SAPSID\SYS\exe to I:\usr\sap\SAPSID\SYS\exe_orig
2.5 Rename I:\usr\sap\SAPSID\SYS\exe_new to I:\usr\sap\SAPSID\SYS\exe

Clear your stat file.

2.6 Delete STAT file per SAP Note 1058988.

Test the new kernel. Make sure that no background jobs will run during testing. Set rdisp/btctime to 0.

2.7 Edit I:\usr\sap\SAPSID\SYS\profile\SAPSID_DVEBMGS_HOSTNAME and change rdisp/btctime to 0 (take note of the original value)

2.8 Start your SAP services (e.g SAP,SAPOScol)

2.9 Perform verification after restart. Use transaction SICK, SM51, SM50, SMLG, SPAD, DB02, SM21, ST22

2.10 If OK.Stop the SAP system again.

Perform revert of rdisp/btctime original value.

2.11 Edit I:\usr\sap\SAPSID\SYS\profile\SAPSID_DVEBMGS_HOSTNAME and change rdisp/btctime to its original value
2.12 Start SAP system
… Using Services Admin, start SAPOSCol
… Using Services Admin, start SAP_Inst# and enable Automatic startup
… Using SAP MMC, right click on SID then select Start"
2.13 Perform verification after restart. Use transaction SICK, SM51, SM50, SMLG, SPAD, DB02, SM21, ST22.

3.0 Post Work

3.1 Perform load generator by executing SGEN > Regenerate Existing Loads > Distribute load if possible > Immediate
3.2 Wait for Load Generator to complete.

Common errors:

I. Yellow dispatcher > Check disp+work.exe and sapstartsrv.exe if they are the same.
II. Yellow dispatcher > Install Microsoft DLL, as per SAP Note 684106. This is often not necessary