Upgrade SAP Pacemaker clusters from ENSA1 to ENSA2

Configure the parameters in the default profile.

If you want to upgrade to ENSA2 while staying on the same SAP release or if your target release defaults to ENSA1, set the parameters in the default profile (DEFAULT.PFL file) to the following values.

enq/enable=TRUE
enq/serverhost=sapascsvirt
enq/serverinst=10        (instance number of ASCS/SCS instance)
enque/process_location=REMOTESA
enq/replicatorhost=sapersvirt
enq/replicatorinst=11    (instance number of ERS instance)
  

where sapascsvirt is the virtual hostname for the ASCS instances, and sapersvirt is the virtual hostname for the ERS instances. You can change these to fit your target environment.

Configure the ASCS/SCS instance profile.

If you want to upgrade to ENSA2 while staying on the same SAP release or if your target release defaults to ENSA1, set the following parameters in the ASCS/SCS instance profile. 

The section of the profile where ENSA1 is defined looks something like the following.

#--------------------------------------------------------------
Start SAP enqueue server
#-------------------------------------------------------------- 
_EN = en.sap$(SAPSYSTEMNAME)$(INSTANCE_NAME) 
Execute_04 = local rm -f $(_EN) 
Execute_05 = local ln -s -f $(DIR_EXECUTABLE)/enserver$(FT_EXE) $(_EN) 
Start_Program_01 = local $(_EN) pf=$(_PF)
  

To reconfigure this section for ENSA2:

This profile section would look something like the following after your changes.

#--------------------------------------------------------------
Start SAP enqueue server
#-------------------------------------------------------------- 
_ENQ = enq.sap$(SAPSYSTEMNAME)$(INSTANCE_NAME) 
Execute_04 = local rm -f $(_ENQ) 
Execute_05 = local ln -s -f $(DIR_EXECUTABLE)/enq_server$(FT_EXE) $(_ENQ) 
Start_Program_01 = local $(_ENQ) pf=$(_PF) 
... 
enq/server/replication/enable = TRUE 
Autostart = 0

Configure the ERS profile.

If you want to upgrade to ENSA2 while staying on the same SAP release or if your target release defaults to ENSA1, set the following parameters in the ERS instance profile.

Find the section where the enqueue replicator is defined. It will be similar to the following.

#------------------------------------------------------
Start enqueue replication server
#------------------------------------------------------ 
_ER = er.sap$(SAPSYSTEMNAME)$(INSTANCE_NAME) 
Execute_03 = local rm -f $(_ER) 
Execute_04 = local ln -s -f $(DIR_EXECUTABLE)/enrepserver$(FT_EXE) $(_ER) 
Start_Program_00 = local $(_ER) pf=$(_PF) NR=$(SCSID)
  

To reconfigure this section for Enqueue Replicator 2:

This profile section should look something like the following after your changes.

#------------------------------------------------------
Start enqueue replication server
#------------------------------------------------------ 
_ENQR = enqr.sap$(SAPSYSTEMNAME)$(INSTANCE_NAME) 
Execute_01 = local rm -f $(_ENQR) 
Execute_02 = local ln -s -f $(DIR_EXECUTABLE)/enq_replicator$(FT_EXE) $(_ENQR) 
Start_Program_00 = local $(_ENQR) pf=$(_PF) NR=$(SCSID) 
… 
Autostart = 0

Restart SAP Start Services.

After you change the profiles described previously in this epic, restart SAP Start Services for both ASCS/SCS and ERS.

sapcontrol -nr 10 -function RestartService SCT

sapcontrol -nr 11 -function RestartService SCT

where SCT refers to the SAP system ID, and assuming that 10 and 11 are the instance numbers for ASCS/SCS and ERS instances, respectively.

Verify version numbers in SAP resource agents.

When you use SUM to upgrade SAP to S/4HANA 1809 or later, SUM handles the parameter changes in the SAP profiles. Only the cluster requires manual adjustment. However, we recommend that you verify the parameter settings before you make any changes to the cluster.

Check both nodes in the architecture to confirm that the resource-agents package matches the minimum version recommended by SAP. For SLES, check SAP OSS Note 2641019. For RHEL, check SAP OSS Note 2641322. (SAP Notes require an SAP ONE Support Launchpad user account.)

sapers:sctadm 23> zypper search -s -i resource-agents
Loading repository data...
Reading installed packages...
S | Name | Type | Version | Arch | Repository
--+-----------------+---------+------------------------------------+--------+-----------------------------
i | resource-agents | package | 4.8.0+git30.d0077df0-150300.8.28.1 | x86_64 | SLE-Product-HA15-SP3-Updates

Update the resource-agents version if necessary.

Back up cluster configuration.

Back up the CRM cluster configuration as follows.

crm configure show > /tmp/cluster_config_backup.txt

Set maintenance mode.

Set the cluster to maintenance mode.

crm configure property maintenance-mode="true"

Check cluster configuration.

Check the current cluster configuration.

crm configure show

Here is an excerpt from the full output:

node 1: sapascs
node 2: sapers
...
primitive rsc_sap_SCT_ASCS10 SAPInstance \
operations $id=rsc_sap_SCT_ASCS10-operations \
op monitor interval=120 timeout=60 on-fail=restart \
params InstanceName=SCT_ASCS10_sapascsvirt START_PROFILE="/sapmnt/SCT/profile/SCT_ASCS10_sapascsvirt" \ 
   AUTOMATIC_RECOVER=false \
meta resource-stickiness=5000 failure-timeout=60 migration-threshold=1 priority=10
primitive rsc_sap_SCT_ERS11 SAPInstance \
operations $id=rsc_sap_SCT_ERS11-operations \
op monitor interval=120 timeout=60 on-fail=restart \
params InstanceName=SCT_ERS11_sapersvirt START_PROFILE="/sapmnt/SCT/profile/SCT_ERS11_sapersvirt" \
   AUTOMATIC_RECOVER=false IS_ERS=true \
meta priority=1000
...
colocation col_sap_SCT_no_both -5000: grp_SCT_ERS11 grp_SCT_ASCS10
location loc_sap_SCT_failover_to_ers rsc_sap_SCT_ASCS10 \
rule 2000: runs_ers_SCT eq 1
order ord_sap_SCT_first_start_ascs Optional: rsc_sap_SCT_ASCS10:start rsc_sap_SCT_ERS11:stop symmetrical=false
...

where sapascsvirt refers to the virtual hostname for the ASCS instances, sapersvirt refers to the virtual hostname for the ERS instances, and SCT refers to the SAP system ID.

Remove failover colocation constraint.

In the previous example, the location constraint loc_sap_SCT_failover_to_ers  specifies that the ENSA1 feature of ASCS should always follow the ERS instance upon failover. With ENSA2, ASCS should be able to fail over freely to any participating nodes, so you can remove this constraint.

crm configure delete loc_sap_SCT_failover_to_ers

Adjust primitives.

You will also need to make minor changes to the ASCS and ERS SAPInstance primitives.

Here is an example of an ASCS SAPInstance primitive that is configured for ENSA1.

primitive rsc_sap_SCT_ASCS10 SAPInstance \
operations $id=rsc_sap_SCT_ASCS10-operations \
op monitor interval=120 timeout=60 on-fail=restart \
params InstanceName=SCT_ASCS10_sapascsvirt START_PROFILE="/sapmnt/SCT/profile/SCT_ASCS10_sapascsvirt" \
   AUTOMATIC_RECOVER=false \
meta resource-stickiness=5000 failure-timeout=60 migration-threshold=1 priority=10

To upgrade to ENSA2, change this configuration to the following.

primitive rsc_sap_SCT_ASCS10 SAPInstance \
operations $id=rsc_sap_SCT_ASCS10-operations \
op monitor interval=120 timeout=60 on-fail=restart \
params InstanceName=SCT_ASCS10_sapascsvirt START_PROFILE="/sapmnt/SCT/profile/SCT_ASCS10_sapascsvirt" \
   AUTOMATIC_RECOVER=false \
meta resource-stickiness=3000 

This is an example of an ERS SAPInstance primitive that is configured for ENSA1.

primitive rsc_sap_SCT_ERS11 SAPInstance \
operations $id=rsc_sap_SCT_ERS11-operations \
op monitor interval=120 timeout=60 on-fail=restart \
params InstanceName=SCT_ERS11_sapersvirt START_PROFILE="/sapmnt/SCT/profile/SCT_ERS11_sapersvirt" \
   AUTOMATIC_RECOVER=false IS_ERS=true \
meta priority=1000

To upgrade to ENSA2, change this configuration to the following.

primitive rsc_sap_SCT_ERS11 SAPInstance \
operations $id=rsc_sap_SCT_ERS11-operations \
op monitor interval=120 timeout=60 on-fail=restart \
params InstanceName=SCT_ERS11_sapersvirt START_PROFILE="/sapmnt/SCT/profile/SCT_ERS11_sapersvirt" \
   AUTOMATIC_RECOVER=false IS_ERS=true

You can change primitives in various ways. For example, you can revise them in an editor such as vi, as in the following example.

crm configure edit rsc_sap_SCT_ERS11

Disable maintenance mode.

Disable maintenance mode on the cluster.

crm configure property maintenance-mode="false"

When the cluster is out of maintenance mode, it attempts to bring the ASCS and ERS instances online with the new ENSA2 settings.

Review best practices.

Before you add more nodes, make sure to understand best practices such as whether to use an odd or even number of nodes.

Add nodes.

Adding more nodes involves a series of tasks, such as updating the operating system, installing software packages that match the existing nodes, and making mounts available. You can use the Prepare Additional Host option in SAP Software Provisioning Manager (SWPM) to create an SAP-specific baseline of the host. For more information, see the SAP guides listed in the next section.