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High availability for SAP NetWeaver on Azure VMs on Red Hat Enterprise Linux for SAP applications multi-SID

  • Artikkeli

This article describes how to deploy multiple SAP NetWeaver highly available systems (multi-SID) in a two node cluster on Azure VMs with Red Hat Enterprise Linux for SAP applications.

In the example configurations, three SAP NetWeaver 7.50 systems are deployed in a single, two node high availability cluster. The SAP systems SIDs are:

  • NW1: ASCS instance number 00 and virtual host name msnw1ascs. ERS instance number 02 and virtual host name msnw1ers.
  • NW2: ASCS instance number 10 and virtual hostname msnw2ascs. ERS instance number 12 and virtual host name msnw2ers.
  • NW3: ASCS instance number 20 and virtual hostname msnw3ascs. ERS instance number 22 and virtual host name msnw3ers.

The article doesn't cover the database layer and the deployment of the SAP NFS shares.

The examples in this article use the Azure NetApp Files volume sapMSID for the NFS shares, assuming that the volume is already deployed. The examples assume that the Azure NetApp Files volume is deployed with NFSv3 protocol. They use the following file paths for the cluster resources for the ASCS and ERS instances of SAP systems NW1, NW2, and NW3:

  • volume sapMSID (nfs://10.42.0.4/sapmntNW1)
  • volume sapMSID (nfs://10.42.0.4/usrsapNW1ascs)
  • volume sapMSID (nfs://10.42.0.4/usrsapNW1sys)
  • volume sapMSID (nfs://10.42.0.4/usrsapNW1ers)
  • volume sapMSID (nfs://10.42.0.4/sapmntNW2)
  • volume sapMSID (nfs://10.42.0.4/usrsapNW2ascs)
  • volume sapMSID (nfs://10.42.0.4/usrsapNW2sys)
  • volume sapMSID (nfs://10.42.0.4/usrsapNW2ers)
  • volume sapMSID (nfs://10.42.0.4/sapmntNW3)
  • volume sapMSID (nfs://10.42.0.4/usrsapNW3ascs)
  • volume sapMSID (nfs://10.42.0.4/usrsapNW3sys)
  • volume sapMSID (nfs://10.42.0.4/usrsapNW3ers)

Before you begin, refer to the following SAP Notes and papers:

Overview

The virtual machines that participate in the cluster must be sized to be able to run all resources in case failover occurs. Each SAP SID can fail over independently from each other in the multi-SID high availability cluster.

To achieve high availability, SAP NetWeaver requires highly available shares. This article shows examples with the SAP shares deployed on Azure NetApp Files NFS volumes. You could instead host the shares on highly available GlusterFS cluster, which can be used by multiple SAP systems.

Diagram shows S A P NetWeaver High Availability overview with Pacemaker cluster and SAP NFS shares.

Important

The support for multi-SID clustering of SAP ASCS/ERS with Red Hat Linux as guest operating system in Azure VMs is limited to five SAP SIDs on the same cluster. Each new SID increases the complexity. A mix of SAP Enqueue Replication Server 1 and Enqueue Replication Server 2 on the same cluster is not supported. Multi-SID clustering describes the installation of multiple SAP ASCS/ERS instances with different SIDs in one Pacemaker cluster. Currently multi-SID clustering is only supported for ASCS/ERS.

Tip

The multi-SID clustering of SAP ASCS/ERS is a solution with higher complexity. It is more complex to implement. It also involves higher administrative effort, when executing maintenance activities, like OS patching. Before you start the actual implementation, take time to carefully plan out the deployment and all involved components like VMs, NFS mounts, VIPs, load balancer configurations and so on.

SAP NetWeaver ASCS, SAP NetWeaver SCS, and SAP NetWeaver ERS use virtual hostname and virtual IP addresses. On Azure, a load balancer is required to use a virtual IP address. We recommend using Standard load balancer.

  • Frontend IP addresses for ASCS: 10.3.1.50 (NW1), 10.3.1.52 (NW2), and 10.3.1.54 (NW3)
  • Frontend IP addresses for ERS: 10.3.1.51 (NW1), 10.3.1.53 (NW2), and 10.3.1.55 (NW3)
  • Probe port 62000 for NW1 ASCS, 62010 for NW2 ASCS, and 62020 for NW3 ASCS
  • Probe port 62102 for NW1 ASCS, 62112 for NW2 ASCS, and 62122 for NW3 ASCS

Note

When VMs without public IP addresses are placed in the backend pool of internal (no public IP address) Standard Azure load balancer, there is no outbound internet connectivity, unless additional configuration is performed to allow routing to public end points. For details on how to achieve outbound connectivity see Public endpoint connectivity for Virtual Machines using Azure Standard Load Balancer in SAP high-availability scenarios.

Important

Do not enable TCP timestamps on Azure VMs placed behind Azure Load Balancer. Enabling TCP timestamps causes the health probes to fail. Set parameter net.ipv4.tcp_timestamps to 0. For more information, see Load Balancer health probes.

SAP shares

SAP NetWeaver requires shared storage for the transport, profile directory, and so on. For highly available SAP system, it's important to have highly available shares. You need to decide on the architecture for your SAP shares. One option is to deploy the shares on Azure NetApp Files NFS volumes. With Azure NetApp Files, you get built-in high availability for the SAP NFS shares.

Another option is to build GlusterFS on Azure VMs on Red Hat Enterprise Linux for SAP NetWeaver, which can be shared between multiple SAP systems.

Deploy the first SAP system in the cluster

After you decide on the architecture for the SAP shares, deploy the first SAP system in the cluster, following the corresponding documentation.

These articles guide you through the steps to prepare the necessary infrastructure, build the cluster, prepare the OS for running the SAP application.

Tip

Always test the failover functionality of the cluster after the first system is deployed, before adding the additional SAP SIDs to the cluster. That way, you know that the cluster functionality works, before adding the complexity of additional SAP systems to the cluster.

Deploy more SAP systems in the cluster

This example assumes that system NW1 was already deployed in the cluster. This example shows how to deploy SAP systems NW2 and NW3 in the cluster.

The following items are prefixed with:

  • [A] Applicable to all nodes
  • [1] Only applicable to node 1
  • [2] Only applicable to node 2

Prerequisites

Important

Before following the instructions to deploy additional SAP systems in the cluster, deploy the first SAP system in the cluster. There are steps which are only necessary during the first system deployment.

This article assumes that:

  • The Pacemaker cluster is already configured and running.
  • At least one SAP system (ASCS / ERS instance) is already deployed and is running in the cluster.
  • The cluster failover functionality has been tested.
  • The NFS shares for all SAP systems are deployed.

Prepare for SAP NetWeaver Installation

  1. Add configuration for the newly deployed system (that is, NW2 and NW3) to the existing Azure Load Balancer, following the instructions Deploy Azure Load Balancer manually via Azure portal. Adjust the IP addresses, health probe ports, and load-balancing rules for your configuration.

  2. [A] Set up name resolution for the more SAP systems. You can either use DNS server or modify /etc/hosts on all nodes. This example shows how to use the /etc/hosts file. Adapt the IP addresses and the host names to your environment.

    sudo vi /etc/hosts
# IP address of the load balancer frontend configuration for NW2 ASCS
10.3.1.52 msnw2ascs
# IP address of the load balancer frontend configuration for NW3 ASCS
10.3.1.54 msnw3ascs
# IP address of the load balancer frontend configuration for NW2 ERS
10.3.1.53 msnw2ers
# IP address of the load balancer frontend configuration for NW3 ERS
10.3.1.55 msnw3ers

  3. [A] Create the shared directories for the NW2 and NW3 SAP systems to deploy to the cluster.

    sudo mkdir -p /sapmnt/NW2
sudo mkdir -p /usr/sap/NW2/SYS
sudo mkdir -p /usr/sap/NW2/ASCS10
sudo mkdir -p /usr/sap/NW2/ERS12
sudo mkdir -p /sapmnt/NW3
sudo mkdir -p /usr/sap/NW3/SYS
sudo mkdir -p /usr/sap/NW3/ASCS20
sudo mkdir -p /usr/sap/NW3/ERS22


sudo chattr +i /sapmnt/NW2
sudo chattr +i /usr/sap/NW2/SYS
sudo chattr +i /usr/sap/NW2/ASCS10
sudo chattr +i /usr/sap/NW2/ERS12
sudo chattr +i /sapmnt/NW3
sudo chattr +i /usr/sap/NW3/SYS
sudo chattr +i /usr/sap/NW3/ASCS20
sudo chattr +i /usr/sap/NW3/ERS22

  4. [A] Add the mount entries for the /sapmnt/SID and /usr/sap/SID/SYS file systems for the other SAP systems that you're deploying to the cluster. In this example, it's NW2 and NW3.

    Update file /etc/fstab with the file systems for the other SAP systems that you're deploying to the cluster.

Install ASCS / ERS

  1. Create the virtual IP and health probe cluster resources for the ASCS instances of the other SAP systems you're deploying to the cluster. This example uses NW2 and NW3 ASCS, using NFS on Azure NetApp Files volumes with NFSv3 protocol.

    sudo pcs resource create fs_NW2_ASCS Filesystem device='10.42.0.4:/sapMSIDR/usrsapNW2ascs' \
directory='/usr/sap/NW2/ASCS10' fstype='nfs' force_unmount=safe \
op start interval=0 timeout=60 op stop interval=0 timeout=120 op monitor interval=200 timeout=40 \
 --group g-NW2_ASCS

sudo pcs resource create vip_NW2_ASCS IPaddr2 \
ip=10.3.1.52 \
 --group g-NW2_ASCS

sudo pcs resource create nc_NW2_ASCS azure-lb port=62010 \
 --group g-NW2_ASCS

sudo pcs resource create fs_NW3_ASCS Filesystem device='10.42.0.4:/sapMSIDR/usrsapNW3ascs' \
directory='/usr/sap/NW3/ASCS20' fstype='nfs' force_unmount=safe \
op start interval=0 timeout=60 op stop interval=0 timeout=120 op monitor interval=200 timeout=40 \
--group g-NW3_ASCS

sudo pcs resource create vip_NW3_ASCS IPaddr2 \
ip=10.3.1.54 \
--group g-NW3_ASCS

sudo pcs resource create nc_NW3_ASCS azure-lb port=62020 \
--group g-NW3_ASCS

    Make sure the cluster status is ok and that all resources are started. It's not important on which node the resources are running.

  2. [1] Install SAP NetWeaver ASCS.

    Install SAP NetWeaver ASCS as root, using a virtual hostname that maps to the IP address of the load balancer frontend configuration for the ASCS. For example, for system NW2, the virtual hostname is msnw2ascs, 10.3.1.52, and the instance number that you used for the probe of the load balancer, for example 10. For system NW3, the virtual hostname is msnw3ascs, 10.3.1.54, and the instance number that you used for the probe of the load balancer, for example 20. Note down on which cluster node you installed ASCS for each SAP SID.

    You can use the sapinst parameter SAPINST_REMOTE_ACCESS_USER to allow a non-root user to connect to sapinst. You can use parameter SAPINST_USE_HOSTNAME to install SAP, using virtual host name.

    # Allow access to SWPM. This rule is not permanent. If you reboot the machine, you have to run the command again
sudo firewall-cmd --zone=public --add-port=4237/tcp
sudo swpm/sapinst SAPINST_REMOTE_ACCESS_USER=sapadmin SAPINST_USE_HOSTNAME=virtual_hostname

    If the installation fails to create a subfolder in /usr/sap/<SID>/ASCS<Instance#>, try setting the owner to <sid>adm and group to sapsys of the ASCS<Instance#> and retry.

  3. [1] Create a virtual IP and health-probe cluster resources for the ERS instance of the other SAP system you're deploying to the cluster. This example is for NW2 and NW3 ERS, using NFS on Azure NetApp Files volumes with NFSv3 protocol.

    sudo pcs resource create fs_NW2_AERS Filesystem device='10.42.0.4:/sapMSIDR/usrsapNW2ers' \
directory='/usr/sap/NW2/ERS12' fstype='nfs' force_unmount=safe \
op start interval=0 timeout=60 op stop interval=0 timeout=120 op monitor interval=200 timeout=40 \
 --group g-NW2_AERS

sudo pcs resource create vip_NW2_AERS IPaddr2 \
ip=10.3.1.53 \
 --group g-NW2_AERS

sudo pcs resource create nc_NW2_AERS azure-lb port=62112 \
 --group g-NW2_AERS

sudo pcs resource create fs_NW3_AERS Filesystem device='10.42.0.4:/sapMSIDR/usrsapNW3ers' \
directory='/usr/sap/NW3/ERS22' fstype='nfs' force_unmount=safe \
op start interval=0 timeout=60 op stop interval=0 timeout=120 op monitor interval=200 timeout=40 \
 --group g-NW3_AERS

sudo pcs resource create vip_NW3_AERS IPaddr2 \
ip=10.3.1.55 \
 --group g-NW3_AERS

sudo pcs resource create nc_NW3_AERS azure-lb port=62122 \
 --group g-NW3_AERS

    Make sure the cluster status is ok and that all resources are started.

    Next, make sure that the resources of the newly created ERS group are running on the cluster node, opposite to the cluster node where the ASCS instance for the same SAP system was installed. For example, if NW2 ASCS was installed on rhelmsscl1, then make sure the NW2 ERS group is running on rhelmsscl2. You can migrate the NW2 ERS group to rhelmsscl2 by running the following command for one of the cluster resources in the group:

    pcs resource move fs_NW2_AERS rhelmsscl2

  4. [2] Install SAP NetWeaver ERS.

    Install SAP NetWeaver ERS as root on the other node, using a virtual hostname that maps to the IP address of the load balancer frontend configuration for the ERS. For example, for system NW2, the virtual host name is msnw2ers, 10.3.1.53, and the instance number that you used for the probe of the load balancer, for example 12. For system NW3, the virtual host name msnw3ers, 10.3.1.55, and the instance number that you used for the probe of the load balancer, for example 22.

    You can use the sapinst parameter SAPINST_REMOTE_ACCESS_USER to allow a non-root user to connect to sapinst. You can use parameter SAPINST_USE_HOSTNAME to install SAP, using virtual host name.

    # Allow access to SWPM. This rule is not permanent. If you reboot the machine, you have to run the command again
sudo firewall-cmd --zone=public --add-port=4237/tcp
sudo swpm/sapinst SAPINST_REMOTE_ACCESS_USER=sapadmin SAPINST_USE_HOSTNAME=virtual_hostname

    Note

    Use SWPM SP 20 PL 05 or higher. Lower versions do not set the permissions correctly and the installation fails.

    If the installation fails to create a subfolder in /usr/sap/<NW2>/ERS<Instance#>, try setting the owner to <sid>adm and the group to sapsys of the ERS<Instance#> folder and retry.

    If it was necessary for you to migrate the ERS group of the newly deployed SAP system to a different cluster node, don't forget to remove the location constraint for the ERS group. You can remove the constraint by running the following command. This example is given for SAP systems NW2 and NW3. Make sure to remove the temporary constraints for the same resource you used in the command to move the ERS cluster group.

    pcs resource clear fs_NW2_AERS
pcs resource clear fs_NW3_AERS

  5. [1] Adapt the ASCS/SCS and ERS instance profiles for the newly installed SAP systems. The example shown below is for NW2. You need to adapt the ASCS/SCS and ERS profiles for all SAP instances added to the cluster.

    • ASCS/SCS profile

      sudo vi /sapmnt/NW2/profile/NW2_ASCS10_msnw2ascs

# Change the restart command to a start command
#Restart_Program_01 = local $(_EN) pf=$(_PF)
Start_Program_01 = local $(_EN) pf=$(_PF)

# Add the keep alive parameter, if using ENSA1
enque/encni/set_so_keepalive = TRUE

      For both ENSA1 and ENSA2, make sure that the keepalive OS parameters are set as described in SAP note 1410736.

    • ERS profile

      sudo vi /sapmnt/NW2/profile/NW2_ERS12_msnw2ers

# Change the restart command to a start command
#Restart_Program_00 = local $(_ER) pf=$(_PFL) NR=$(SCSID)
Start_Program_00 = local $(_ER) pf=$(_PFL) NR=$(SCSID)

# remove Autostart from ERS profile
# Autostart = 1

  6. [A] Update the /usr/sap/sapservices file.

    To prevent the start of the instances by the sapinit startup script, all instances managed by Pacemaker must be commented out from /usr/sap/sapservices file. The example shown below is for SAP systems NW2 and NW3.

    # Depending on whether the SAP Startup framework is integrated with systemd, you may observe below entries on the node for ASCS instances. You should comment out the line(s). 
# LD_LIBRARY_PATH=/usr/sap/NW2/ASCS10/exe:$LD_LIBRARY_PATH; export LD_LIBRARY_PATH; /usr/sap/NW2/ASCS10/exe/sapstartsrv pf=/usr/sap/NW2/SYS/profile/NW2_ASCS10_msnw2ascs -D -u nw2adm
# LD_LIBRARY_PATH=/usr/sap/NW3/ASCS20/exe:$LD_LIBRARY_PATH; export LD_LIBRARY_PATH; /usr/sap/NW3/ASCS20/exe/sapstartsrv pf=/usr/sap/NW3/SYS/profile/NW3_ASCS20_msnw3ascs -D -u nw3adm
# systemctl --no-ask-password start SAPNW2_10 # sapstartsrv pf=/usr/sap/NW2/SYS/profile/NW2_ASCS10_msnw2ascs
# systemctl --no-ask-password start SAPNW3_20 # sapstartsrv pf=/usr/sap/NW3/SYS/profile/NW3_ASCS20_msnw3ascs

# Depending on whether the SAP Startup framework is integrated with systemd, you may observe below entries on the node for ERS instances. You should comment out the line(s). 
#LD_LIBRARY_PATH=/usr/sap/NW2/ERS12/exe:$LD_LIBRARY_PATH; export LD_LIBRARY_PATH; /usr/sap/NW2/ERS12/exe/sapstartsrv pf=/usr/sap/NW2/ERS12/profile/NW2_ERS12_msnw2ers -D -u nw2adm
#LD_LIBRARY_PATH=/usr/sap/NW3/ERS22/exe:$LD_LIBRARY_PATH; export LD_LIBRARY_PATH; /usr/sap/NW3/ERS22/exe/sapstartsrv pf=/usr/sap/NW3/ERS22/profile/NW3_ERS22_msnw3ers -D -u nw3adm
# systemctl --no-ask-password start SAPNW2_12 # sapstartsrv pf=/usr/sap/NW2/ERS12/profile/NW2_ERS12_msnw2ers
# systemctl --no-ask-password start SAPNW3_22 # sapstartsrv pf=/usr/sap/NW3/ERS22/profile/NW3_ERS22_msnw3ers

    Important

    With the systemd based SAP Startup Framework, SAP instances can now be managed by systemd. The minimum required Red Hat Enterprise Linux (RHEL) version is RHEL 8 for SAP. As described in SAP Note 3115048, a fresh installation of a SAP kernel with integrated systemd based SAP Startup Framework support will always result in a systemd controlled SAP instance. After an SAP kernel upgrade of an existing SAP installation to a kernel which has systemd based SAP Startup Framework support, however, some manual steps have to be performed as documented in SAP Note 3115048 to convert the existing SAP startup environment to one which is systemd controlled.

    When utilizing Red Hat HA services for SAP (cluster configuration) to manage SAP application server instances such as SAP ASCS and SAP ERS, additional modifications will be necessary to ensure compatibility between the SAPInstance resource agent and the new systemd-based SAP startup framework. So once the SAP application server instances has been installed or switched to a systemd enabled SAP Kernel as per SAP Note 3115048, the steps mentioned in Red Hat KBA 6884531 must be completed successfully on all cluster nodes.

  7. [1] Create the SAP cluster resources for the newly installed SAP system.

    Depending on whether you are running an ENSA1 or ENSA2 system, select respective tab to define the resources for SAP systems NW2 and NW3 as follows. SAP introduced support for ENSA2, including replication, in SAP NetWeaver 7.52. Starting with ABAP Platform 1809, ENSA2 is installed by default. For ENSA2 support, see SAP Note 2630416 for enqueue server 2 support.

    If you use enqueue server 2 architecture (ENSA2), install resource agent resource-agents-sap-4.1.1-12.el7.x86_64 or newer and define the resources for SAP systems NW2 and NW3 as follows:

    sudo pcs property set maintenance-mode=true

sudo pcs resource create rsc_sap_NW2_ASCS10 SAPInstance \
InstanceName=NW2_ASCS10_msnw2ascs START_PROFILE="/sapmnt/NW2/profile/NW2_ASCS10_msnw2ascs" \
AUTOMATIC_RECOVER=false \
meta resource-stickiness=5000 migration-threshold=1 failure-timeout=60 \
op monitor interval=20 on-fail=restart timeout=60 \
op start interval=0 timeout=600 op stop interval=0 timeout=600 \
--group g-NW2_ASCS

sudo pcs resource meta g-NW2_ASCS resource-stickiness=3000

sudo pcs resource create rsc_sap_NW2_ERS12 SAPInstance \
InstanceName=NW2_ERS12_msnw2ers START_PROFILE="/sapmnt/NW2/profile/NW2_ERS12_msnw2ers" \
AUTOMATIC_RECOVER=false IS_ERS=true \
op monitor interval=20 on-fail=restart timeout=60 op start interval=0 timeout=600 op stop interval=0 timeout=600 \
--group g-NW2_AERS

sudo pcs constraint colocation add g-NW2_AERS with g-NW2_ASCS -5000
sudo pcs constraint location rsc_sap_NW2_ASCS10 rule score=2000 runs_ers_NW2 eq 1
sudo pcs constraint order start g-NW2_ASCS then stop g-NW2_AERS kind=Optional symmetrical=false

sudo pcs resource create rsc_sap_NW3_ASCS20 SAPInstance \
InstanceName=NW3_ASCS20_msnw3ascs START_PROFILE="/sapmnt/NW3/profile/NW3_ASCS20_msnw3ascs" \
AUTOMATIC_RECOVER=false \
meta resource-stickiness=5000 migration-threshold=1 failure-timeout=60 \
op monitor interval=20 on-fail=restart timeout=60 \
op start interval=0 timeout=600 op stop interval=0 timeout=600 \
--group g-NW3_ASCS

sudo pcs resource meta g-NW3_ASCS resource-stickiness=3000

sudo pcs resource create rsc_sap_NW3_ERS22 SAPInstance \
InstanceName=NW3_ERS22_msnw3ers START_PROFILE="/sapmnt/NW3/profile/NW2_ERS22_msnw3ers" \
AUTOMATIC_RECOVER=false IS_ERS=true \
op monitor interval=20 on-fail=restart timeout=60 op start interval=0 timeout=600 op stop interval=0 timeout=600 \
--group g-NW3_AERS

sudo pcs constraint colocation add g-NW3_AERS with g-NW3_ASCS -5000
sudo pcs constraint location rsc_sap_NW3_ASCS20 rule score=2000 runs_ers_NW3 eq 1
sudo pcs constraint order start g-NW3_ASCS then stop g-NW3_AERS kind=Optional symmetrical=false

sudo pcs property set maintenance-mode=false

    If you're upgrading from an older version and switching to enqueue server 2, see SAP note 2641019.

    Note

    The timeouts in the above configuration are just examples and might need to be adapted to the specific SAP setup.

    Make sure that the cluster status is ok and that all resources are started. It's not important on which node the resources are running. The following example shows the cluster resources status, after SAP systems NW2 and NW3 were added to the cluster.

    sudo pcs status

# Online: [ rhelmsscl1 rhelmsscl2 ]

# Full list of resources:

# rsc_st_azure   (stonith:fence_azure_arm):      Started rhelmsscl1
# Resource Group: g-NW1_ASCS
#   fs_NW1_ASCS        (ocf::heartbeat:Filesystem):    Started rhelmsscl1
#   vip_NW1_ASCS       (ocf::heartbeat:IPaddr2):       Started rhelmsscl1
#   nc_NW1_ASCS        (ocf::heartbeat:azure-lb):      Started rhelmsscl1
#   rsc_sap_NW1_ASCS00 (ocf::heartbeat:SAPInstance):   Started rhelmsscl1
# Resource Group: g-NW1_AERS
#   fs_NW1_AERS        (ocf::heartbeat:Filesystem):    Started rhelmsscl2
#   vip_NW1_AERS       (ocf::heartbeat:IPaddr2):       Started rhelmsscl2
#   nc_NW1_AERS        (ocf::heartbeat:azure-lb):      Started rhelmsscl2
#   rsc_sap_NW1_ERS02  (ocf::heartbeat:SAPInstance):   Started rhelmsscl2
# Resource Group: g-NW2_ASCS
#   fs_NW2_ASCS        (ocf::heartbeat:Filesystem):    Started rhelmsscl1
#   vip_NW2_ASCS       (ocf::heartbeat:IPaddr2):       Started rhelmsscl1
#   nc_NW2_ASCS        (ocf::heartbeat:azure-lb):      Started rhelmsscl1
#   rsc_sap_NW2_ASCS10 (ocf::heartbeat:SAPInstance):   Started rhelmsscl1
# Resource Group: g-NW2_AERS
#   fs_NW2_AERS        (ocf::heartbeat:Filesystem):    Started rhelmsscl1
#   vip_NW2_AERS       (ocf::heartbeat:IPaddr2):       Started rhelmsscl1
#   nc_NW2_AERS        (ocf::heartbeat:azure-lb):      Started rhelmsscl1
#   rsc_sap_NW2_ERS12  (ocf::heartbeat:SAPInstance):   Started rhelmsscl1
# Resource Group: g-NW3_ASCS
#   fs_NW3_ASCS        (ocf::heartbeat:Filesystem):    Started rhelmsscl1
#   vip_NW3_ASCS       (ocf::heartbeat:IPaddr2):       Started rhelmsscl1
#   nc_NW3_ASCS        (ocf::heartbeat:azure-lb):      Started rhelmsscl1
#   rsc_sap_NW3_ASCS20 (ocf::heartbeat:SAPInstance):   Started rhelmsscl1
# Resource Group: g-NW3_AERS
#   fs_NW3_AERS        (ocf::heartbeat:Filesystem):    Started rhelmsscl1
#   vip_NW3_AERS       (ocf::heartbeat:IPaddr2):       Started rhelmsscl1
#   nc_NW3_AERS        (ocf::heartbeat:azure-lb):      Started rhelmsscl1
#  rsc_sap_NW3_ERS22  (ocf::heartbeat:SAPInstance):   Started rhelmsscl1

  8. [A] Add firewall rules for ASCS and ERS on both nodes. The example below shows the firewall rules for both SAP systems NW2 and NW3.

    # NW1 - ASCS
sudo firewall-cmd --zone=public --add-port={62010,3210,3610,3910,8110,51013,51014,51016}/tcp --permanent
sudo firewall-cmd --zone=public --add-port={62010,3210,3610,3910,8110,51013,51014,51016}/tcp
# NW2 - ERS
sudo firewall-cmd --zone=public --add-port={62112,3212,3312,51213,51214,51216}/tcp --permanent
sudo firewall-cmd --zone=public --add-port={62112,3212,3312,51213,51214,51216}/tcp
# NW3 - ASCS
sudo firewall-cmd --zone=public --add-port={62020,3220,3620,3920,8120,52013,52014,52016}/tcp --permanent
sudo firewall-cmd --zone=public --add-port={62020,3220,3620,3920,8120,52013,52014,52016}/tcp
# NW3 - ERS
sudo firewall-cmd --zone=public --add-port={62122,3222,3322,52213,52214,52216}/tcp --permanent
sudo firewall-cmd --zone=public --add-port={62122,3222,3322,52213,52214,52216}/tcp

Proceed with the SAP installation

Complete your SAP installation by:

Test the multi-SID cluster setup

The following tests are a subset of the test cases in the best practices guides of Red Hat. They're included for your convenience. For the full list of cluster tests, reference the following documentation:

Always read the Red Hat best practices guides and perform all other tests that might have been added. The tests that are presented are in a two-node, multi-SID cluster with three SAP systems installed.

  1. Manually migrate the ASCS instance. The example shows migrating the ASCS instance for SAP system NW3.

    Resource state before starting the test:

    Online: [ rhelmsscl1 rhelmsscl2 ]

Full list of resources:

rsc_st_azure   (stonith:fence_azure_arm):      Started rhelmsscl1
Resource Group: g-NW1_ASCS
    fs_NW1_ASCS        (ocf::heartbeat:Filesystem):    Started rhelmsscl1
    vip_NW1_ASCS       (ocf::heartbeat:IPaddr2):       Started rhelmsscl1
    nc_NW1_ASCS        (ocf::heartbeat:azure-lb):      Started rhelmsscl1
    rsc_sap_NW1_ASCS00 (ocf::heartbeat:SAPInstance):   Started rhelmsscl1
Resource Group: g-NW1_AERS
    fs_NW1_AERS        (ocf::heartbeat:Filesystem):    Started rhelmsscl2
    vip_NW1_AERS       (ocf::heartbeat:IPaddr2):       Started rhelmsscl2
    nc_NW1_AERS        (ocf::heartbeat:azure-lb):      Started rhelmsscl2
    rsc_sap_NW1_ERS02  (ocf::heartbeat:SAPInstance):   Started rhelmsscl2
Resource Group: g-NW2_ASCS
    fs_NW2_ASCS        (ocf::heartbeat:Filesystem):    Started rhelmsscl2
    vip_NW2_ASCS       (ocf::heartbeat:IPaddr2):       Started rhelmsscl2
    nc_NW2_ASCS        (ocf::heartbeat:azure-lb):      Started rhelmsscl2
    rsc_sap_NW2_ASCS10 (ocf::heartbeat:SAPInstance):   Started rhelmsscl2
Resource Group: g-NW2_AERS
    fs_NW2_AERS        (ocf::heartbeat:Filesystem):    Started rhelmsscl1
    vip_NW2_AERS       (ocf::heartbeat:IPaddr2):       Started rhelmsscl1
    nc_NW2_AERS        (ocf::heartbeat:azure-lb):      Started rhelmsscl1
    rsc_sap_NW2_ERS12  (ocf::heartbeat:SAPInstance):   Started rhelmsscl1
Resource Group: g-NW3_ASCS
    fs_NW3_ASCS        (ocf::heartbeat:Filesystem):    Started rhelmsscl2
    vip_NW3_ASCS       (ocf::heartbeat:IPaddr2):       Started rhelmsscl2
    nc_NW3_ASCS        (ocf::heartbeat:azure-lb):      Started rhelmsscl2
    rsc_sap_NW3_ASCS20 (ocf::heartbeat:SAPInstance):   Started rhelmsscl2
Resource Group: g-NW3_AERS
    fs_NW3_AERS        (ocf::heartbeat:Filesystem):    Started rhelmsscl1
    vip_NW3_AERS       (ocf::heartbeat:IPaddr2):       Started rhelmsscl1
    nc_NW3_AERS        (ocf::heartbeat:azure-lb):      Started rhelmsscl1
    rsc_sap_NW3_ERS22  (ocf::heartbeat:SAPInstance):   Started rhelmsscl1

    Run the following commands as root to migrate the NW3 ASCS instance.

    pcs resource move rsc_sap_NW3_ASCS200
# Clear temporary migration constraints
pcs resource clear rsc_sap_NW3_ASCS20

# Remove failed actions for the ERS that occurred as part of the migration
pcs resource cleanup rsc_sap_NW3_ERS22

    Resource state after the test:

    Online: [ rhelmsscl1 rhelmsscl2 ]

Full list of resources:

rsc_st_azure   (stonith:fence_azure_arm):      Started rhelmsscl1
Resource Group: g-NW1_ASCS
    fs_NW1_ASCS        (ocf::heartbeat:Filesystem):    Started rhelmsscl1
    vip_NW1_ASCS       (ocf::heartbeat:IPaddr2):       Started rhelmsscl1
    nc_NW1_ASCS        (ocf::heartbeat:azure-lb):      Started rhelmsscl1
    rsc_sap_NW1_ASCS00 (ocf::heartbeat:SAPInstance):   Started rhelmsscl1
Resource Group: g-NW1_AERS
    fs_NW1_AERS        (ocf::heartbeat:Filesystem):    Started rhelmsscl2
    vip_NW1_AERS       (ocf::heartbeat:IPaddr2):       Started rhelmsscl2
    nc_NW1_AERS        (ocf::heartbeat:azure-lb):      Started rhelmsscl2
    rsc_sap_NW1_ERS02  (ocf::heartbeat:SAPInstance):   Started rhelmsscl2
Resource Group: g-NW2_ASCS
    fs_NW2_ASCS        (ocf::heartbeat:Filesystem):    Started rhelmsscl2
    vip_NW2_ASCS       (ocf::heartbeat:IPaddr2):       Started rhelmsscl2
    nc_NW2_ASCS        (ocf::heartbeat:azure-lb):      Started rhelmsscl2
    rsc_sap_NW2_ASCS10 (ocf::heartbeat:SAPInstance):   Started rhelmsscl2
Resource Group: g-NW2_AERS
    fs_NW2_AERS        (ocf::heartbeat:Filesystem):    Started rhelmsscl1
    vip_NW2_AERS       (ocf::heartbeat:IPaddr2):       Started rhelmsscl1
    nc_NW2_AERS        (ocf::heartbeat:azure-lb):      Started rhelmsscl1
    rsc_sap_NW2_ERS12  (ocf::heartbeat:SAPInstance):   Started rhelmsscl1
Resource Group: g-NW3_ASCS
    fs_NW3_ASCS        (ocf::heartbeat:Filesystem):    Started rhelmsscl1
    vip_NW3_ASCS       (ocf::heartbeat:IPaddr2):       Started rhelmsscl1
    nc_NW3_ASCS        (ocf::heartbeat:azure-lb):      Started rhelmsscl1
    rsc_sap_NW3_ASCS20 (ocf::heartbeat:SAPInstance):   Started rhelmsscl1
Resource Group: g-NW3_AERS
    fs_NW3_AERS        (ocf::heartbeat:Filesystem):    Started rhelmsscl2
    vip_NW3_AERS       (ocf::heartbeat:IPaddr2):       Started rhelmsscl2
    nc_NW3_AERS        (ocf::heartbeat:azure-lb):      Started rhelmsscl2
    rsc_sap_NW3_ERS22  (ocf::heartbeat:SAPInstance):   Started rhelmsscl2

  2. Simulate node crash.

    Resource state before starting the test:

    Online: [ rhelmsscl1 rhelmsscl2 ]

Full list of resources:

rsc_st_azure   (stonith:fence_azure_arm):      Started rhelmsscl1
Resource Group: g-NW1_ASCS
    fs_NW1_ASCS        (ocf::heartbeat:Filesystem):    Started rhelmsscl1
    vip_NW1_ASCS       (ocf::heartbeat:IPaddr2):       Started rhelmsscl1
    nc_NW1_ASCS        (ocf::heartbeat:azure-lb):      Started rhelmsscl1
    rsc_sap_NW1_ASCS00 (ocf::heartbeat:SAPInstance):   Started rhelmsscl1
Resource Group: g-NW1_AERS
    fs_NW1_AERS        (ocf::heartbeat:Filesystem):    Started rhelmsscl2
    vip_NW1_AERS       (ocf::heartbeat:IPaddr2):       Started rhelmsscl2
    nc_NW1_AERS        (ocf::heartbeat:azure-lb):      Started rhelmsscl2
    rsc_sap_NW1_ERS02  (ocf::heartbeat:SAPInstance):   Started rhelmsscl2
Resource Group: g-NW2_ASCS
    fs_NW2_ASCS        (ocf::heartbeat:Filesystem):    Started rhelmsscl1
    vip_NW2_ASCS       (ocf::heartbeat:IPaddr2):       Started rhelmsscl1
    nc_NW2_ASCS        (ocf::heartbeat:azure-lb):      Started rhelmsscl1
    rsc_sap_NW2_ASCS10 (ocf::heartbeat:SAPInstance):   Started rhelmsscl1
Resource Group: g-NW2_AERS
    fs_NW2_AERS        (ocf::heartbeat:Filesystem):    Started rhelmsscl2
    vip_NW2_AERS       (ocf::heartbeat:IPaddr2):       Started rhelmsscl2
    nc_NW2_AERS        (ocf::heartbeat:azure-lb):      Started rhelmsscl2
    rsc_sap_NW2_ERS12  (ocf::heartbeat:SAPInstance):   Started rhelmsscl2
Resource Group: g-NW3_ASCS
    fs_NW3_ASCS        (ocf::heartbeat:Filesystem):    Started rhelmsscl1
    vip_NW3_ASCS       (ocf::heartbeat:IPaddr2):       Started rhelmsscl1
    nc_NW3_ASCS        (ocf::heartbeat:azure-lb):      Started rhelmsscl1
    rsc_sap_NW3_ASCS20 (ocf::heartbeat:SAPInstance):   Started rhelmsscl1
Resource Group: g-NW3_AERS
    fs_NW3_AERS        (ocf::heartbeat:Filesystem):    Started rhelmsscl2
    vip_NW3_AERS       (ocf::heartbeat:IPaddr2):       Started rhelmsscl2
    nc_NW3_AERS        (ocf::heartbeat:azure-lb):      Started rhelmsscl2
    rsc_sap_NW3_ERS22  (ocf::heartbeat:SAPInstance):   Started rhelmsscl2

    Run the following command as root on a node where at least one ASCS instance is running. This example runs the command on rhelmsscl1, where the ASCS instances for NW1, NW2, and NW3 are running.

    echo c > /proc/sysrq-trigger

    The status after the test and after the node that was crashed has started again, should look like these results:

    Full list of resources:

rsc_st_azure    (stonith:fence_azure_arm):      Started rhelmsscl2
Resource Group: g-NW1_ASCS
    fs_NW1_ASCS        (ocf::heartbeat:Filesystem):    Started rhelmsscl2
    vip_NW1_ASCS       (ocf::heartbeat:IPaddr2):       Started rhelmsscl2
    nc_NW1_ASCS        (ocf::heartbeat:azure-lb):      Started rhelmsscl2
    rsc_sap_NW1_ASCS00 (ocf::heartbeat:SAPInstance):   Started rhelmsscl2
Resource Group: g-NW1_AERS
    fs_NW1_AERS        (ocf::heartbeat:Filesystem):    Started rhelmsscl1
    vip_NW1_AERS       (ocf::heartbeat:IPaddr2):       Started rhelmsscl1
    nc_NW1_AERS        (ocf::heartbeat:azure-lb):      Started rhelmsscl1
    rsc_sap_NW1_ERS02  (ocf::heartbeat:SAPInstance):   Started rhelmsscl1
Resource Group: g-NW2_ASCS
    fs_NW2_ASCS        (ocf::heartbeat:Filesystem):    Started rhelmsscl2
    vip_NW2_ASCS       (ocf::heartbeat:IPaddr2):       Started rhelmsscl2
    nc_NW2_ASCS        (ocf::heartbeat:azure-lb):      Started rhelmsscl2
    rsc_sap_NW2_ASCS10 (ocf::heartbeat:SAPInstance):   Started rhelmsscl2
Resource Group: g-NW2_AERS
    fs_NW2_AERS        (ocf::heartbeat:Filesystem):    Started rhelmsscl1
    vip_NW2_AERS       (ocf::heartbeat:IPaddr2):       Started rhelmsscl1
    nc_NW2_AERS        (ocf::heartbeat:azure-lb):      Started rhelmsscl1
    rsc_sap_NW2_ERS12  (ocf::heartbeat:SAPInstance):   Started rhelmsscl1
Resource Group: g-NW3_ASCS
    fs_NW3_ASCS        (ocf::heartbeat:Filesystem):    Started rhelmsscl2
    vip_NW3_ASCS       (ocf::heartbeat:IPaddr2):       Started rhelmsscl2
    nc_NW3_ASCS        (ocf::heartbeat:azure-lb):      Started rhelmsscl2
    rsc_sap_NW3_ASCS20 (ocf::heartbeat:SAPInstance):   Started rhelmsscl2
Resource Group: g-NW3_AERS
    fs_NW3_AERS        (ocf::heartbeat:Filesystem):    Started rhelmsscl1
    vip_NW3_AERS       (ocf::heartbeat:IPaddr2):       Started rhelmsscl1
    nc_NW3_AERS        (ocf::heartbeat:azure-lb):      Started rhelmsscl1
    rsc_sap_NW3_ERS22  (ocf::heartbeat:SAPInstance):   Started rhelmsscl1

    If there are messages for failed resources, clean the status of the failed resources. For example:

    pcs resource cleanup rsc_sap_NW1_ERS02

Next steps

To learn how to establish high availability and plan for disaster recovery of SAP HANA on Azure VMs, see High Availability of SAP HANA on Azure Virtual Machines (VMs).