High availability for SAP NetWeaver on Azure VMs on SUSE Linux Enterprise Server for SAP applications

This article describes how to deploy the virtual machines, configure the virtual machines, install the cluster framework, and install a highly available SAP NetWeaver or SAP ABAP platform based system. In the example configurations, ASCS instance number 00, ERS instance number 02, and SAP System ID NW1 is used.

For new implementations on SLES for SAP Applications 15, we recommended deploying high availability for SAP ASCS/ERS in simple mount configuration. The classic Pacemaker configuration, based on cluster-controlled file systems for the SAP central services directories, described in this article is still supported.

Read the following SAP Notes and papers first

Overview

To achieve high availability, SAP NetWeaver requires an NFS server. The NFS server is configured in a separate cluster and can be used by multiple SAP systems.

SAP NetWeaver High Availability overview

The NFS server, SAP NetWeaver ASCS, SAP NetWeaver SCS, SAP NetWeaver ERS, and the SAP HANA database 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. The presented configuration shows a load balancer with:

  • Frontend IP address 10.0.0.7 for ASCS
  • Frontend IP address 10.0.0.8 for ERS
  • Probe port 62000 for ASCS
  • Probe port 62101 for ERS

Setting up a highly available NFS server

Note

We recommend deploying one of the Azure first-party NFS services: NFS on Azure Files or NFS ANF volumes for storing shared data in a highly available SAP system. Be aware that we are de-emphasizing SAP reference architectures, utilizing NFS clusters.
The SAP configuration guides for SAP NW highly available SAP system with native NFS services are:

SAP NetWeaver requires shared storage for the transport and profile directory. Read High availability for NFS on Azure VMs on SUSE Linux Enterprise Server on how to set up an NFS server for SAP NetWeaver.

Prepare infrastructure

The resource agent for SAP Instance is included in SUSE Linux Enterprise Server for SAP Applications. An image for SUSE Linux Enterprise Server for SAP Applications 12 or 15 is available in Azure Marketplace. You can use the image to deploy new VMs.

Deploy Linux VMs manually via Azure portal

This document assumes that you've already deployed a resource group, Azure Virtual Network, and subnet.

Deploy virtual machines with SLES for SAP Applications image. Choose a suitable version of SLES image that is supported for SAP system. You can deploy VM in any one of the availability options - virtual machine scale set, availability zone, or availability set.

Configure Azure load balancer

During VM configuration, you have an option to create or select exiting load balancer in networking section. Follow the steps below to configure a standard load balancer for the high-availability setup of SAP ASCS and SAP ERS.

Follow create load balancer guide to set up a standard load balancer for a high availability SAP system using the Azure portal. During the setup of load balancer, consider following points.

  1. Frontend IP Configuration: Create two frontend IP, one for ASCS and another for ERS. Select the same virtual network and subnet as your ASCS/ERS virtual machines.
  2. Backend Pool: Create backend pool and add ASCS and ERS VMs.
  3. Inbound rules: Create two load balancing rule, one for ASCS and another for ERS. Follow the same steps for both load balancing rules.
    • Frontend IP address: Select frontend IP
    • Backend pool: Select backend pool
    • Check "High availability ports"
    • Protocol: TCP
    • Health Probe: Create health probe with below details (applies for both ASCS or ERS)
      • Protocol: TCP
      • Port: [for example: 620<Instance-no.> for ASCS, 621<Instance-no.> for ERS]
      • Interval: 5
      • Probe Threshold: 2
    • Idle timeout (minutes): 30
    • Check "Enable Floating IP"

Note

Health probe configuration property numberOfProbes, otherwise known as "Unhealthy threshold" in Portal, isn't respected. So to control the number of successful or failed consecutive probes, set the property "probeThreshold" to 2. It is currently not possible to set this property using Azure portal, so use either the Azure CLI or PowerShell command.

Note

When VMs without public IP addresses are placed in the backend pool of internal (no public IP address) Standard Azure load balancer, there will be 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

  • Don't enable TCP time stamps on Azure VMs placed behind Azure Load Balancer. Enabling TCP timestamps will cause the health probes to fail. Set the net.ipv4.tcp_timestamps parameter to 0. For details, see Load Balancer health probes.
  • To prevent saptune from changing the manually set net.ipv4.tcp_timestamps value from 0 back to 1, you should update saptune version to 3.1.1 or higher. For more details, see saptune 3.1.1 – Do I Need to Update?.

Setting up (A)SCS

Next, you'll prepare and install the SAP ASCS and ERS instances.

Create Pacemaker cluster

Follow the steps in Setting up Pacemaker on SUSE Linux Enterprise Server in Azure to create a basic Pacemaker cluster for this (A)SCS server.

Installation

The following items are prefixed with either [A] - applicable to all nodes, [1] - only applicable to node 1, or [2] - only applicable to node 2.

  1. [A] Install SUSE Connector

    sudo zypper install sap-suse-cluster-connector
    

    Note

    The known issue with using a dash in host names is fixed with version 3.1.1 of package sap-suse-cluster-connector. Make sure that you are using at least version 3.1.1 of package sap-suse-cluster-connector, if using cluster nodes with dash in the host name. Otherwise your cluster will not work.

    Make sure that you installed the new version of the SAP SUSE cluster connector. The old one was called sap_suse_cluster_connector and the new one is called sap-suse-cluster-connector.

    sudo zypper info sap-suse-cluster-connector
    
    Information for package sap-suse-cluster-connector:
    ---------------------------------------------------
    Repository     : SLE-12-SP3-SAP-Updates
    Name           : sap-suse-cluster-connector
    <b>Version        : 3.0.0-2.2</b>
    Arch           : noarch
    Vendor         : SUSE LLC <https://www.suse.com/>
    Support Level  : Level 3
    Installed Size : 41.6 KiB
    <b>Installed      : Yes</b>
    Status         : up-to-date
    Source package : sap-suse-cluster-connector-3.0.0-2.2.src
    Summary        : SUSE High Availability Setup for SAP Products
    
  2. [A] Update SAP resource agents

    A patch for the resource-agents package is required to use the new configuration that is described in this article. You can check, if the patch is already installed with the following command

    sudo grep 'parameter name="IS_ERS"' /usr/lib/ocf/resource.d/heartbeat/SAPInstance
    

    The output should be similar to

    <parameter name="IS_ERS" unique="0" required="0">
    

    If the grep command doesn't find the IS_ERS parameter, you need to install the patch listed on the SUSE download page.

    # example for patch for SLES 12 SP1
    sudo zypper in -t patch SUSE-SLE-HA-12-SP1-2017-885=1
    # example for patch for SLES 12 SP2
    sudo zypper in -t patch SUSE-SLE-HA-12-SP2-2017-886=1
    
  3. [A] Setup host name resolution

    You can either use a DNS server or modify the /etc/hosts on all nodes. This example shows how to use the /etc/hosts file. Replace the IP address and the hostname in the following commands.

    sudo vi /etc/hosts
    
    # Insert the following lines to /etc/hosts. Change the IP address and hostname to match your environment
    # IP address of the load balancer frontend configuration for NFS
    10.0.0.4 nw1-nfs
    # IP address of the load balancer frontend configuration for SAP NetWeaver ASCS
    10.0.0.7 nw1-ascs
    # IP address of the load balancer frontend configuration for SAP NetWeaver ASCS ERS
    10.0.0.8 nw1-aers
    # IP address of the load balancer frontend configuration for database
    10.0.0.13 nw1-db
    

Prepare for SAP NetWeaver installation

  1. [A] Create the shared directories

    sudo mkdir -p /sapmnt/NW1
    sudo mkdir -p /usr/sap/trans
    sudo mkdir -p /usr/sap/NW1/SYS
    sudo mkdir -p /usr/sap/NW1/ASCS00
    sudo mkdir -p /usr/sap/NW1/ERS02
    
    sudo chattr +i /sapmnt/NW1
    sudo chattr +i /usr/sap/trans
    sudo chattr +i /usr/sap/NW1/SYS
    sudo chattr +i /usr/sap/NW1/ASCS00
    sudo chattr +i /usr/sap/NW1/ERS02
    
  2. [A] Configure autofs

    sudo vi /etc/auto.master
    
    # Add the following line to the file, save and exit
    +auto.master
    /- /etc/auto.direct
    

    Create a file with

    sudo vi /etc/auto.direct
    
    # Add the following lines to the file, save and exit
    /sapmnt/NW1 -nfsvers=4,nosymlink,sync nw1-nfs:/NW1/sapmntsid
    /usr/sap/trans -nfsvers=4,nosymlink,sync nw1-nfs:/NW1/trans
    /usr/sap/NW1/SYS -nfsvers=4,nosymlink,sync nw1-nfs:/NW1/sidsys
    

    Restart autofs to mount the new shares

    sudo systemctl enable autofs
    sudo service autofs restart
    
  3. [A] Configure SWAP file

    Create a swap file as defined in Create a SWAP file for an Azure Linux VM

    #!/bin/sh
    
    # Percent of space on the ephemeral disk to dedicate to swap. Here 30% is being used. Modify as appropriate.
    PCT=0.3
    
    # Location of swap file. Modify as appropriate based on location of ephemeral disk.
    LOCATION=/mnt
    
    if [ ! -f ${LOCATION}/swapfile ]
    then
    
        # Get size of the ephemeral disk and multiply it by the percent of space to allocate
        size=$(/bin/df -m --output=target,avail | /usr/bin/awk -v percent="$PCT" -v pattern=${LOCATION} '$0 ~ pattern {SIZE=int($2*percent);print SIZE}')
        echo "$size MB of space allocated to swap file"
    
         # Create an empty file first and set correct permissions
        /bin/dd if=/dev/zero of=${LOCATION}/swapfile bs=1M count=$size
        /bin/chmod 0600 ${LOCATION}/swapfile
    
        # Make the file available to use as swap
        /sbin/mkswap ${LOCATION}/swapfile
    fi
    
    # Enable swap
    /sbin/swapon ${LOCATION}/swapfile
    /sbin/swapon -a
    
    # Display current swap status
    /sbin/swapon -s
    

    Make the file executable.

    chmod +x /var/lib/cloud/scripts/per-boot/swap.sh
    

    Stop and start the VM. Stopping and starting the VM is only necessary the first time after you create the SWAP file.

Installing SAP NetWeaver ASCS/ERS

  1. [1] Create a virtual IP resource and health-probe for the ASCS instance

    Important

    Recent testing revealed situations, where netcat stops responding to requests due to backlog and its limitation of handling only one connection. The netcat resource stops listening to the Azure Load balancer requests and the floating IP becomes unavailable.
    For existing Pacemaker clusters, we recommended in the past replacing netcat with socat. Currently we recommend using azure-lb resource agent, which is part of package resource-agents, with the following package version requirements:

    • For SLES 12 SP4/SP5, the version must be at least resource-agents-4.3.018.a7fb5035-3.30.1.
    • For SLES 15/15 SP1, the version must be at least resource-agents-4.3.0184.6ee15eb2-4.13.1.

    Note that the change will require brief downtime.
    For existing Pacemaker clusters, if the configuration was already changed to use socat as described in Azure Load-Balancer Detection Hardening, there is no requirement to switch immediately to azure-lb resource agent.

    sudo crm node standby nw1-cl-1
    
    sudo crm configure primitive fs_NW1_ASCS Filesystem device='nw1-nfs:/NW1/ASCS' directory='/usr/sap/NW1/ASCS00' fstype='nfs4' \
      op start timeout=60s interval=0 \
      op stop timeout=60s interval=0 \
      op monitor interval=20s timeout=40s
    
    sudo crm configure primitive vip_NW1_ASCS IPaddr2 \
      params ip=10.0.0.7 \
      op monitor interval=10 timeout=20
    
    sudo crm configure primitive nc_NW1_ASCS azure-lb port=62000 \
      op monitor timeout=20s interval=10
    
    sudo crm configure group g-NW1_ASCS fs_NW1_ASCS nc_NW1_ASCS vip_NW1_ASCS \
       meta resource-stickiness=3000
    

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

    sudo crm_mon -r
    
    # Node nw1-cl-1: standby
    # Online: [ nw1-cl-0 ]
    # 
    # Full list of resources:
    # 
    # stonith-sbd     (stonith:external/sbd): Started nw1-cl-0
    #  Resource Group: g-NW1_ASCS
    #      fs_NW1_ASCS        (ocf::heartbeat:Filesystem):    Started nw1-cl-0
    #      nc_NW1_ASCS        (ocf::heartbeat:azure-lb):      Started nw1-cl-0
    #      vip_NW1_ASCS       (ocf::heartbeat:IPaddr2):       Started nw1-cl-0
    
  2. [1] Install SAP NetWeaver ASCS

    Install SAP NetWeaver ASCS as root on the first node using a virtual hostname that maps to the IP address of the load balancer frontend configuration for the ASCS, for example nw1-ascs, 10.0.0.7 and the instance number that you used for the probe of the load balancer, for example 00.

    You can use the sapinst parameter SAPINST_REMOTE_ACCESS_USER to allow a non-root user to connect to sapinst.

    sudo <swpm>/sapinst SAPINST_REMOTE_ACCESS_USER=sapadmin SAPINST_USE_HOSTNAME=virtual_hostname
    

    If the installation fails to create a subfolder in /usr/sap/NW1/ASCS00, try setting the owner and group of the ASCS00 folder and retry.

    chown nw1adm /usr/sap/NW1/ASCS00
    chgrp sapsys /usr/sap/NW1/ASCS00
    
  3. [1] Create a virtual IP resource and health-probe for the ERS instance

    sudo crm node online nw1-cl-1
    sudo crm node standby nw1-cl-0
    
    sudo crm configure primitive fs_NW1_ERS Filesystem device='nw1-nfs:/NW1/ASCSERS' directory='/usr/sap/NW1/ERS02' fstype='nfs4' \
      op start timeout=60s interval=0 \
      op stop timeout=60s interval=0 \
      op monitor interval=20s timeout=40s
    
    sudo crm configure primitive vip_NW1_ERS IPaddr2 \
      params ip=10.0.0.8 \
      op monitor interval=10 timeout=20
    
    sudo crm configure primitive nc_NW1_ERS azure-lb port=62102 \
      op monitor timeout=20s interval=10
    
    sudo crm configure group g-NW1_ERS fs_NW1_ERS nc_NW1_ERS vip_NW1_ERS
    

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

    sudo crm_mon -r
    
    # Node nw1-cl-0: standby
    # Online: [ nw1-cl-1 ]
    # 
    # Full list of resources:
    #
    # stonith-sbd     (stonith:external/sbd): Started nw1-cl-1
    #  Resource Group: g-NW1_ASCS
    #      fs_NW1_ASCS        (ocf::heartbeat:Filesystem):    Started nw1-cl-1
    #      nc_NW1_ASCS        (ocf::heartbeat:azure-lb):      Started nw1-cl-1
    #      vip_NW1_ASCS       (ocf::heartbeat:IPaddr2):       Started nw1-cl-1
    #  Resource Group: g-NW1_ERS
    #      fs_NW1_ERS (ocf::heartbeat:Filesystem):    Started nw1-cl-1
    #      nc_NW1_ERS (ocf::heartbeat:azure-lb):      Started nw1-cl-1
    #      vip_NW1_ERS        (ocf::heartbeat:IPaddr2):       Started nw1-cl-1
    
  4. [2] Install SAP NetWeaver ERS

    Install SAP NetWeaver ERS as root on the second node using a virtual hostname that maps to the IP address of the load balancer frontend configuration for the ERS, for example nw1-aers, 10.0.0.8 and the instance number that you used for the probe of the load balancer, for example 02.

    You can use the sapinst parameter SAPINST_REMOTE_ACCESS_USER to allow a non-root user to connect to sapinst.

    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 will fail.

    If the installation fails to create a subfolder in /usr/sap/NW1/ERS02, try setting the owner and group of the ERS02 folder and retry.

    chown nw1adm /usr/sap/NW1/ERS02
    chgrp sapsys /usr/sap/NW1/ERS02
    
  5. [1] Adapt the ASCS/SCS and ERS instance profiles

    • ASCS/SCS profile

      sudo vi /sapmnt/NW1/profile/NW1_ASCS00_nw1-ascs
      
      # Change the restart command to a start command
      #Restart_Program_01 = local $(_EN) pf=$(_PF)
      Start_Program_01 = local $(_EN) pf=$(_PF)
      
      # Add the following lines
      service/halib = $(DIR_CT_RUN)/saphascriptco.so
      service/halib_cluster_connector = /usr/bin/sap_suse_cluster_connector
      
      # 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/NW1/profile/NW1_ERS02_nw1-aers
      
      # 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)
      
      # Add the following lines
      service/halib = $(DIR_CT_RUN)/saphascriptco.so
      service/halib_cluster_connector = /usr/bin/sap_suse_cluster_connector
      
      # remove Autostart from ERS profile
      # Autostart = 1
      
  6. [A] Configure Keep Alive

    The communication between the SAP NetWeaver application server and the ASCS/SCS is routed through a software load balancer. The load balancer disconnects inactive connections after a configurable timeout. To prevent this you need to set a parameter in the SAP NetWeaver ASCS/SCS profile, if using ENSA1, and change the Linux system keepalive settings on all SAP servers for both ENSA1/ENSA2. Read SAP Note 1410736 for more information.

    # Change the Linux system configuration
    sudo sysctl net.ipv4.tcp_keepalive_time=300
    
  7. [A] Configure the SAP users after the installation

    # Add sidadm to the haclient group
    sudo usermod -aG haclient nw1adm
    
  8. [1] Add the ASCS and ERS SAP services to the sapservice file

    Add the ASCS service entry to the second node and copy the ERS service entry to the first node.

    cat /usr/sap/sapservices | grep ASCS00 | sudo ssh nw1-cl-1 "cat >>/usr/sap/sapservices"
    sudo ssh nw1-cl-1 "cat /usr/sap/sapservices" | grep ERS02 | sudo tee -a /usr/sap/sapservices
    
  9. [A] Disabling systemd services of the ASCS and ERS SAP instance. This step is only applicable, if SAP startup framework is managed by systemd as per SAP Note 3115048

    Note

    When managing SAP instances like SAP ASCS and SAP ERS using SLES cluster configuration, you would need to make additional modifications to integrate the cluster with the native systemd-based SAP start framework. This ensures that maintenance procedures do no compromise cluster stability. After installation or switching SAP startup framework to systemd-enabled setup as per SAP Note 3115048, you should disable the systemd services for the ASCS and ERS SAP instances.

    # Stop ASCS and ERS instances using <sid>adm
    sapcontrol -nr 00 -function Stop
    sapcontrol -nr 00 -function StopService
    
    sapcontrol -nr 01 -function Stop
    sapcontrol -nr 01 -function StopService
    
    # Execute below command on VM where you have performed ASCS instance installation (e.g. nw1-cl-0)
    sudo systemctl disable SAPNW1_00
    # Execute below command on VM where you have performed ERS instance installation (e.g. nw1-cl-1)
    sudo systemctl disable SAPNW1_01
    
  10. [1] Create the SAP cluster resources

    Depending on whether you are running an ENSA1 or ENSA2 system, select respective tab to define the resources. 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.

    sudo crm configure property maintenance-mode="true"
    
    sudo crm configure primitive rsc_sap_NW1_ASCS00 SAPInstance \
      operations \$id=rsc_sap_NW1_ASCS00-operations \
      op monitor interval=11 timeout=60 on-fail=restart \
      params InstanceName=NW1_ASCS00_nw1-ascs START_PROFILE="/sapmnt/NW1/profile/NW1_ASCS00_nw1-ascs" \
      AUTOMATIC_RECOVER=false \
      meta resource-stickiness=5000 failure-timeout=60 migration-threshold=1 priority=10
    
    sudo crm configure primitive rsc_sap_NW1_ERS02 SAPInstance \
      operations \$id=rsc_sap_NW1_ERS02-operations \
      op monitor interval=11 timeout=60 on-fail=restart \
      params InstanceName=NW1_ERS02_nw1-aers START_PROFILE="/sapmnt/NW1/profile/NW1_ERS02_nw1-aers" AUTOMATIC_RECOVER=false IS_ERS=true \
      meta priority=1000
    
    sudo crm configure modgroup g-NW1_ASCS add rsc_sap_NW1_ASCS00
    sudo crm configure modgroup g-NW1_ERS add rsc_sap_NW1_ERS02
    
    sudo crm configure colocation col_sap_NW1_no_both -5000: g-NW1_ERS g-NW1_ASCS
    sudo crm configure location loc_sap_NW1_failover_to_ers rsc_sap_NW1_ASCS00 rule 2000: runs_ers_NW1 eq 1
    sudo crm configure order ord_sap_NW1_first_start_ascs Optional: rsc_sap_NW1_ASCS00:start rsc_sap_NW1_ERS02:stop symmetrical=false
    
    sudo crm_attribute --delete --name priority-fencing-delay
    
    sudo crm node online nw1-cl-0
    sudo crm configure property maintenance-mode="false"
    

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

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

sudo crm_mon -r
 
# Online: [ nw1-cl-0 nw1-cl-1 ]
#
# Full list of resources:
#
# stonith-sbd     (stonith:external/sbd): Started nw1-cl-1
#  Resource Group: g-NW1_ASCS
#      fs_NW1_ASCS        (ocf::heartbeat:Filesystem):    Started nw1-cl-1
#      nc_NW1_ASCS        (ocf::heartbeat:azure-lb):      Started nw1-cl-1
#      vip_NW1_ASCS       (ocf::heartbeat:IPaddr2):       Started nw1-cl-1
#      rsc_sap_NW1_ASCS00 (ocf::heartbeat:SAPInstance):   Started nw1-cl-1
#  Resource Group: g-NW1_ERS
#      fs_NW1_ERS (ocf::heartbeat:Filesystem):    Started nw1-cl-0
#      nc_NW1_ERS (ocf::heartbeat:azure-lb):      Started nw1-cl-0
#      vip_NW1_ERS        (ocf::heartbeat:IPaddr2):       Started nw1-cl-0
#      rsc_sap_NW1_ERS02  (ocf::heartbeat:SAPInstance):   Started nw1-cl-0

SAP NetWeaver application server preparation

Some databases require that the database instance installation is executed on an application server. Prepare the application server virtual machines to be able to use them in these cases.

The steps bellow assume that you install the application server on a server different from the ASCS/SCS and HANA servers. Otherwise some of the steps below (like configuring host name resolution) aren't needed.

  1. Configure operating system

    Reduce the size of the dirty cache. For more information, see Low write performance on SLES 11/12 servers with large RAM.

    sudo vi /etc/sysctl.conf
    
    # Change/set the following settings
    vm.dirty_bytes = 629145600
    vm.dirty_background_bytes = 314572800
    
  2. Set up host name resolution

    You can either use a DNS server or modify the /etc/hosts on all nodes. This example shows how to use the /etc/hosts file. Replace the IP address and the hostname in the following commands

    sudo vi /etc/hosts
    

    Insert the following lines to /etc/hosts. Change the IP address and hostname to match your environment

    # IP address of the load balancer frontend configuration for NFS
    10.0.0.4 nw1-nfs
    # IP address of the load balancer frontend configuration for SAP NetWeaver ASCS/SCS
    10.0.0.7 nw1-ascs
    # IP address of the load balancer frontend configuration for SAP NetWeaver ERS
    10.0.0.8 nw1-aers
    # IP address of the load balancer frontend configuration for database
    10.0.0.13 nw1-db
    # IP address of all application servers
    10.0.0.20 nw1-di-0
    10.0.0.21 nw1-di-1
    
  3. Create the sapmnt directory

    sudo mkdir -p /sapmnt/NW1
    sudo mkdir -p /usr/sap/trans
    
    sudo chattr +i /sapmnt/NW1
    sudo chattr +i /usr/sap/trans
    
  4. Configure autofs

    sudo vi /etc/auto.master
    
    # Add the following line to the file, save and exit
    +auto.master
    /- /etc/auto.direct
    

    Create a new file with

    sudo vi /etc/auto.direct
    
    # Add the following lines to the file, save and exit
    /sapmnt/NW1 -nfsvers=4,nosymlink,sync nw1-nfs:/NW1/sapmntsid
    /usr/sap/trans -nfsvers=4,nosymlink,sync nw1-nfs:/NW1/trans
    

    Restart autofs to mount the new shares

    sudo systemctl enable autofs
    sudo service autofs restart
    
  5. Configure SWAP file

    sudo vi /etc/waagent.conf
    
    # Set the property ResourceDisk.EnableSwap to y
    # Create and use swapfile on resource disk.
    ResourceDisk.EnableSwap=y
    
    # Set the size of the SWAP file with property ResourceDisk.SwapSizeMB
    # The free space of resource disk varies by virtual machine size. Make sure that you do not set a value that is too big. You can check the SWAP space with command swapon
    # Size of the swapfile.
    ResourceDisk.SwapSizeMB=2000
    

    Restart the Agent to activate the change

    sudo service waagent restart
    

Install database

In this example, SAP NetWeaver is installed on SAP HANA. You can use every supported database for this installation. For more information on how to install SAP HANA in Azure, see High Availability of SAP HANA on Azure Virtual Machines (VMs). For a list of supported databases, see SAP Note 1928533.

  1. Run the SAP database instance installation

    Install the SAP NetWeaver database instance as root using a virtual hostname that maps to the IP address of the load balancer frontend configuration for the database, for example, nw1-db and 10.0.0.13.

    You can use the sapinst parameter SAPINST_REMOTE_ACCESS_USER to allow a non-root user to connect to sapinst.

    sudo <swpm>/sapinst SAPINST_REMOTE_ACCESS_USER=sapadmin SAPINST_USE_HOSTNAME=virtual_hostname
    

SAP NetWeaver application server installation

Follow these steps to install an SAP application server.

  1. Prepare application server

    Follow the steps in the chapter SAP NetWeaver application server preparation above to prepare the application server.

  2. Install SAP NetWeaver application server

    Install a primary or additional SAP NetWeaver applications server.

    You can use the sapinst parameter SAPINST_REMOTE_ACCESS_USER to allow a non-root user to connect to sapinst.

    sudo <swpm>/sapinst SAPINST_REMOTE_ACCESS_USER=sapadmin SAPINST_USE_HOSTNAME=virtual_hostname
    
  3. Update SAP HANA secure store

    Update the SAP HANA secure store to point to the virtual name of the SAP HANA System Replication setup.

    Run the following command to list the entries

    hdbuserstore List
    

    This should list all entries and should look similar to

    DATA FILE       : /home/nw1adm/.hdb/nw1-di-0/SSFS_HDB.DAT
    KEY FILE        : /home/nw1adm/.hdb/nw1-di-0/SSFS_HDB.KEY
    
    KEY DEFAULT
      ENV : 10.0.0.14:30313
      USER: SAPABAP1
      DATABASE: HN1
    

    The output shows that the IP address of the default entry is pointing to the virtual machine and not to the load balancer's IP address. This entry needs to be changed to point to the virtual hostname of the load balancer. Make sure to use the same port (30313 in the output above) and database name (HN1 in the output above)!

    su - nw1adm
    hdbuserstore SET DEFAULT nw1-db:30313@HN1 SAPABAP1 <password of ABAP schema>
    

Test the cluster setup

The following tests are a copy of the test cases in the best practices guides of SUSE. They're copied for your convenience. Always also read the best practices guides and perform all additional tests that might have been added.

  1. Test HAGetFailoverConfig, HACheckConfig and HACheckFailoverConfig

    Run the following commands as <sapsid>adm on the node where the ASCS instance is currently running. If the commands fail with FAIL: Insufficient memory, it might be caused by dashes in your hostname. This is a known issue and will be fixed by SUSE in the sap-suse-cluster-connector package.

    nw1-cl-0:nw1adm 54> sapcontrol -nr 00 -function HAGetFailoverConfig
    
    # 15.08.2018 13:50:36
    # HAGetFailoverConfig
    # OK
    # HAActive: TRUE
    # HAProductVersion: Toolchain Module
    # HASAPInterfaceVersion: Toolchain Module (sap_suse_cluster_connector 3.0.1)
    # HADocumentation: https://www.suse.com/products/sles-for-sap/resource-library/sap-best-practices/
    # HAActiveNode:
    # HANodes: nw1-cl-0, nw1-cl-1
    
    nw1-cl-0:nw1adm 55> sapcontrol -nr 00 -function HACheckConfig
    
    # 15.08.2018 14:00:04
    # HACheckConfig
    # OK
    # state, category, description, comment
    # SUCCESS, SAP CONFIGURATION, Redundant ABAP instance configuration, 2 ABAP instances detected
    # SUCCESS, SAP CONFIGURATION, Redundant Java instance configuration, 0 Java instances detected
    # SUCCESS, SAP CONFIGURATION, Enqueue separation, All Enqueue server separated from application server
    # SUCCESS, SAP CONFIGURATION, MessageServer separation, All MessageServer separated from application server
    # SUCCESS, SAP CONFIGURATION, ABAP instances on multiple hosts, ABAP instances on multiple hosts detected
    # SUCCESS, SAP CONFIGURATION, Redundant ABAP SPOOL service configuration, 2 ABAP instances with SPOOL service detected
    # SUCCESS, SAP STATE, Redundant ABAP SPOOL service state, 2 ABAP instances with active SPOOL service detected
    # SUCCESS, SAP STATE, ABAP instances with ABAP SPOOL service on multiple hosts, ABAP instances with active ABAP SPOOL service on multiple hosts detected
    # SUCCESS, SAP CONFIGURATION, Redundant ABAP BATCH service configuration, 2 ABAP instances with BATCH service detected
    # SUCCESS, SAP STATE, Redundant ABAP BATCH service state, 2 ABAP instances with active BATCH service detected
    # SUCCESS, SAP STATE, ABAP instances with ABAP BATCH service on multiple hosts, ABAP instances with active ABAP BATCH service on multiple hosts detected
    # SUCCESS, SAP CONFIGURATION, Redundant ABAP DIALOG service configuration, 2 ABAP instances with DIALOG service detected
    # SUCCESS, SAP STATE, Redundant ABAP DIALOG service state, 2 ABAP instances with active DIALOG service detected
    # SUCCESS, SAP STATE, ABAP instances with ABAP DIALOG service on multiple hosts, ABAP instances with active ABAP DIALOG service on multiple hosts detected
    # SUCCESS, SAP CONFIGURATION, Redundant ABAP UPDATE service configuration, 2 ABAP instances with UPDATE service detected
    # SUCCESS, SAP STATE, Redundant ABAP UPDATE service state, 2 ABAP instances with active UPDATE service detected
    # SUCCESS, SAP STATE, ABAP instances with ABAP UPDATE service on multiple hosts, ABAP instances with active ABAP UPDATE service on multiple hosts detected
    # SUCCESS, SAP STATE, SCS instance running, SCS instance status ok
    # SUCCESS, SAP CONFIGURATION, SAPInstance RA sufficient version (nw1-ascs_NW1_00), SAPInstance includes is-ers patch
    # SUCCESS, SAP CONFIGURATION, Enqueue replication (nw1-ascs_NW1_00), Enqueue replication enabled
    # SUCCESS, SAP STATE, Enqueue replication state (nw1-ascs_NW1_00), Enqueue replication active
    
    nw1-cl-0:nw1adm 56> sapcontrol -nr 00 -function HACheckFailoverConfig
    
    # 15.08.2018 14:04:08
    # HACheckFailoverConfig
    # OK
    # state, category, description, comment
    # SUCCESS, SAP CONFIGURATION, SAPInstance RA sufficient version, SAPInstance includes is-ers patch
    
  2. Manually migrate the ASCS instance

    Resource state before starting the test:

    stonith-sbd     (stonith:external/sbd): Started nw1-cl-0
     Resource Group: g-NW1_ASCS
         fs_NW1_ASCS        (ocf::heartbeat:Filesystem):    Started nw1-cl-0
         nc_NW1_ASCS        (ocf::heartbeat:azure-lb):      Started nw1-cl-0
         vip_NW1_ASCS       (ocf::heartbeat:IPaddr2):       Started nw1-cl-0
         rsc_sap_NW1_ASCS00 (ocf::heartbeat:SAPInstance):   Started nw1-cl-0
     Resource Group: g-NW1_ERS
         fs_NW1_ERS (ocf::heartbeat:Filesystem):    Started nw1-cl-1
         nc_NW1_ERS (ocf::heartbeat:azure-lb):      Started nw1-cl-1
         vip_NW1_ERS        (ocf::heartbeat:IPaddr2):       Started nw1-cl-1
         rsc_sap_NW1_ERS02  (ocf::heartbeat:SAPInstance):   Started nw1-cl-1
    

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

    nw1-cl-0:~ # crm resource migrate rsc_sap_NW1_ASCS00 force
    # INFO: Move constraint created for rsc_sap_NW1_ASCS00
    
    nw1-cl-0:~ # crm resource unmigrate rsc_sap_NW1_ASCS00
    # INFO: Removed migration constraints for rsc_sap_NW1_ASCS00
    
    # Remove failed actions for the ERS that occurred as part of the migration
    nw1-cl-0:~ # crm resource cleanup rsc_sap_NW1_ERS02
    

    Resource state after the test:

    stonith-sbd     (stonith:external/sbd): Started nw1-cl-0
     Resource Group: g-NW1_ASCS
         fs_NW1_ASCS        (ocf::heartbeat:Filesystem):    Started nw1-cl-1
         nc_NW1_ASCS        (ocf::heartbeat:azure-lb):      Started nw1-cl-1
         vip_NW1_ASCS       (ocf::heartbeat:IPaddr2):       Started nw1-cl-1
         rsc_sap_NW1_ASCS00 (ocf::heartbeat:SAPInstance):   Started nw1-cl-1
     Resource Group: g-NW1_ERS
         fs_NW1_ERS (ocf::heartbeat:Filesystem):    Started nw1-cl-0
         nc_NW1_ERS (ocf::heartbeat:azure-lb):      Started nw1-cl-0
         vip_NW1_ERS        (ocf::heartbeat:IPaddr2):       Started nw1-cl-0
         rsc_sap_NW1_ERS02  (ocf::heartbeat:SAPInstance):   Started nw1-cl-0
    
  3. Test HAFailoverToNode

    Resource state before starting the test:

    stonith-sbd     (stonith:external/sbd): Started nw1-cl-0
     Resource Group: g-NW1_ASCS
         fs_NW1_ASCS        (ocf::heartbeat:Filesystem):    Started nw1-cl-1
         nc_NW1_ASCS        (ocf::heartbeat:azure-lb):      Started nw1-cl-1
         vip_NW1_ASCS       (ocf::heartbeat:IPaddr2):       Started nw1-cl-1
         rsc_sap_NW1_ASCS00 (ocf::heartbeat:SAPInstance):   Started nw1-cl-1
     Resource Group: g-NW1_ERS
         fs_NW1_ERS (ocf::heartbeat:Filesystem):    Started nw1-cl-0
         nc_NW1_ERS (ocf::heartbeat:azure-lb):      Started nw1-cl-0
         vip_NW1_ERS        (ocf::heartbeat:IPaddr2):       Started nw1-cl-0
         rsc_sap_NW1_ERS02  (ocf::heartbeat:SAPInstance):   Started nw1-cl-0
    

    Run the following commands as <sapsid>adm to migrate the ASCS instance.

    nw1-cl-0:nw1adm 55> sapcontrol -nr 00 -host nw1-ascs -user nw1adm <password> -function HAFailoverToNode ""
    
    # run as root
    # Remove failed actions for the ERS that occurred as part of the migration
    nw1-cl-0:~ # crm resource cleanup rsc_sap_NW1_ERS02
    # Remove migration constraints
    nw1-cl-0:~ # crm resource clear rsc_sap_NW1_ASCS00
    #INFO: Removed migration constraints for rsc_sap_NW1_ASCS00
    

    Resource state after the test:

    stonith-sbd     (stonith:external/sbd): Started nw1-cl-0
     Resource Group: g-NW1_ASCS
         fs_NW1_ASCS        (ocf::heartbeat:Filesystem):    Started nw1-cl-0
         nc_NW1_ASCS        (ocf::heartbeat:azure-lb):      Started nw1-cl-0
         vip_NW1_ASCS       (ocf::heartbeat:IPaddr2):       Started nw1-cl-0
         rsc_sap_NW1_ASCS00 (ocf::heartbeat:SAPInstance):   Started nw1-cl-0
     Resource Group: g-NW1_ERS
         fs_NW1_ERS (ocf::heartbeat:Filesystem):    Started nw1-cl-1
         nc_NW1_ERS (ocf::heartbeat:azure-lb):      Started nw1-cl-1
         vip_NW1_ERS        (ocf::heartbeat:IPaddr2):       Started nw1-cl-1
         rsc_sap_NW1_ERS02  (ocf::heartbeat:SAPInstance):   Started nw1-cl-1
    
  4. Simulate node crash

    Resource state before starting the test:

    stonith-sbd     (stonith:external/sbd): Started nw1-cl-0
     Resource Group: g-NW1_ASCS
         fs_NW1_ASCS        (ocf::heartbeat:Filesystem):    Started nw1-cl-0
         nc_NW1_ASCS        (ocf::heartbeat:azure-lb):      Started nw1-cl-0
         vip_NW1_ASCS       (ocf::heartbeat:IPaddr2):       Started nw1-cl-0
         rsc_sap_NW1_ASCS00 (ocf::heartbeat:SAPInstance):   Started nw1-cl-0
     Resource Group: g-NW1_ERS
         fs_NW1_ERS (ocf::heartbeat:Filesystem):    Started nw1-cl-1
         nc_NW1_ERS (ocf::heartbeat:azure-lb):      Started nw1-cl-1
         vip_NW1_ERS        (ocf::heartbeat:IPaddr2):       Started nw1-cl-1
         rsc_sap_NW1_ERS02  (ocf::heartbeat:SAPInstance):   Started nw1-cl-1
    

    Run the following command as root on the node where the ASCS instance is running

    nw1-cl-0:~ # echo b > /proc/sysrq-trigger
    

    If you use SBD, Pacemaker shouldn't automatically start on the killed node. The status after the node is started again should look like this.

    Online: [ nw1-cl-1 ]
    OFFLINE: [ nw1-cl-0 ]
    
    Full list of resources:
    
    stonith-sbd     (stonith:external/sbd): Started nw1-cl-1
     Resource Group: g-NW1_ASCS
         fs_NW1_ASCS        (ocf::heartbeat:Filesystem):    Started nw1-cl-1
         nc_NW1_ASCS        (ocf::heartbeat:azure-lb):      Started nw1-cl-1
         vip_NW1_ASCS       (ocf::heartbeat:IPaddr2):       Started nw1-cl-1
         rsc_sap_NW1_ASCS00 (ocf::heartbeat:SAPInstance):   Started nw1-cl-1
     Resource Group: g-NW1_ERS
         fs_NW1_ERS (ocf::heartbeat:Filesystem):    Started nw1-cl-1
         nc_NW1_ERS (ocf::heartbeat:azure-lb):      Started nw1-cl-1
         vip_NW1_ERS        (ocf::heartbeat:IPaddr2):       Started nw1-cl-1
         rsc_sap_NW1_ERS02  (ocf::heartbeat:SAPInstance):   Started nw1-cl-1
    
    Failed Actions:
    * rsc_sap_NW1_ERS02_monitor_11000 on nw1-cl-1 'not running' (7): call=219, status=complete, exitreason='none',
        last-rc-change='Wed Aug 15 14:38:38 2018', queued=0ms, exec=0ms
    

    Use the following commands to start Pacemaker on the killed node, clean the SBD messages, and clean the failed resources.

    # run as root
    # list the SBD device(s)
    nw1-cl-0:~ # cat /etc/sysconfig/sbd | grep SBD_DEVICE=
    # SBD_DEVICE="/dev/disk/by-id/scsi-36001405772fe8401e6240c985857e116;/dev/disk/by-id/scsi-36001405034a84428af24ddd8c3a3e9e1;/dev/disk/by-id/scsi-36001405cdd5ac8d40e548449318510c3"
    
    nw1-cl-0:~ # sbd -d /dev/disk/by-id/scsi-36001405772fe8401e6240c985857e116 -d /dev/disk/by-id/scsi-36001405034a84428af24ddd8c3a3e9e1 -d /dev/disk/by-id/scsi-36001405cdd5ac8d40e548449318510c3 message nw1-cl-0 clear
    
    nw1-cl-0:~ # systemctl start pacemaker
    nw1-cl-0:~ # crm resource cleanup rsc_sap_NW1_ASCS00
    nw1-cl-0:~ # crm resource cleanup rsc_sap_NW1_ERS02
    

    Resource state after the test:

    stonith-sbd     (stonith:external/sbd): Started nw1-cl-1
     Resource Group: g-NW1_ASCS
         fs_NW1_ASCS        (ocf::heartbeat:Filesystem):    Started nw1-cl-1
         nc_NW1_ASCS        (ocf::heartbeat:azure-lb):      Started nw1-cl-1
         vip_NW1_ASCS       (ocf::heartbeat:IPaddr2):       Started nw1-cl-1
         rsc_sap_NW1_ASCS00 (ocf::heartbeat:SAPInstance):   Started nw1-cl-1
     Resource Group: g-NW1_ERS
         fs_NW1_ERS (ocf::heartbeat:Filesystem):    Started nw1-cl-0
         nc_NW1_ERS (ocf::heartbeat:azure-lb):      Started nw1-cl-0
         vip_NW1_ERS        (ocf::heartbeat:IPaddr2):       Started nw1-cl-0
         rsc_sap_NW1_ERS02  (ocf::heartbeat:SAPInstance):   Started nw1-cl-0
    
  5. Blocking network communication

    Resource state before starting the test:

    stonith-sbd     (stonith:external/sbd): Started nw1-cl-1
     Resource Group: g-NW1_ASCS
         fs_NW1_ASCS        (ocf::heartbeat:Filesystem):    Started nw1-cl-1
         nc_NW1_ASCS        (ocf::heartbeat:azure-lb):      Started nw1-cl-1
         vip_NW1_ASCS       (ocf::heartbeat:IPaddr2):       Started nw1-cl-1
         rsc_sap_NW1_ASCS00 (ocf::heartbeat:SAPInstance):   Started nw1-cl-1
     Resource Group: g-NW1_ERS
         fs_NW1_ERS (ocf::heartbeat:Filesystem):    Started nw1-cl-0
         nc_NW1_ERS (ocf::heartbeat:azure-lb):      Started nw1-cl-0
         vip_NW1_ERS        (ocf::heartbeat:IPaddr2):       Started nw1-cl-0
         rsc_sap_NW1_ERS02  (ocf::heartbeat:SAPInstance):   Started nw1-cl-0
    

    Execute firewall rule to block the communication on one of the nodes.

    # Execute iptable rule on nw1-cl-0 (10.0.0.5) to block the incoming and outgoing traffic to nw1-cl-1 (10.0.0.6)
    iptables -A INPUT -s 10.0.0.6 -j DROP; iptables -A OUTPUT -d 10.0.0.6 -j DROP
    

    When cluster nodes can't communicate to each other, there's a risk of a split-brain scenario. In such situations, cluster nodes will try to simultaneously fence each other, resulting in fence race.

    When configuring a fencing device, it's recommended to configure pcmk_delay_max property. So, in the event of split-brain scenario, the cluster introduces a random delay up to the pcmk_delay_max value, to the fencing action on each node. The node with the shortest delay will be selected for fencing.

    Additionally, in ENSA 2 configuration, to prioritize the node hosting the ASCS resource over the other node during a split brain scenario, it's recommended to configure priority-fencing-delay property in the cluster. Enabling priority-fencing-delay property allows the cluster to introduce an additional delay in the fencing action specifically on the node hosting the ASCS resource, allowing the ASCS node to win the fence race.

    Execute below command to delete the firewall rule.

    # If the iptables rule set on the server gets reset after a reboot, the rules will be cleared out. In case they have not been reset, please proceed to remove the iptables rule using the following command.
    iptables -D INPUT -s 10.0.0.6 -j DROP; iptables -D OUTPUT -d 10.0.0.6 -j DROP
    
  6. Test manual restart of ASCS instance

    Resource state before starting the test:

    stonith-sbd     (stonith:external/sbd): Started nw1-cl-1
     Resource Group: g-NW1_ASCS
         fs_NW1_ASCS        (ocf::heartbeat:Filesystem):    Started nw1-cl-1
         nc_NW1_ASCS        (ocf::heartbeat:azure-lb):      Started nw1-cl-1
         vip_NW1_ASCS       (ocf::heartbeat:IPaddr2):       Started nw1-cl-1
         rsc_sap_NW1_ASCS00 (ocf::heartbeat:SAPInstance):   Started nw1-cl-1
     Resource Group: g-NW1_ERS
         fs_NW1_ERS (ocf::heartbeat:Filesystem):    Started nw1-cl-0
         nc_NW1_ERS (ocf::heartbeat:azure-lb):      Started nw1-cl-0
         vip_NW1_ERS        (ocf::heartbeat:IPaddr2):       Started nw1-cl-0
         rsc_sap_NW1_ERS02  (ocf::heartbeat:SAPInstance):   Started nw1-cl-0
    

    Create an enqueue lock by, for example edit a user in transaction su01. Run the following commands as <sapsid>adm on the node where the ASCS instance is running. The commands will stop the ASCS instance and start it again. If using enqueue server 1 architecture, the enqueue lock is expected to be lost in this test. If using enqueue server 2 architecture, the enqueue will be retained.

    nw1-cl-1:nw1adm 54> sapcontrol -nr 00 -function StopWait 600 2
    

    The ASCS instance should now be disabled in Pacemaker

    rsc_sap_NW1_ASCS00 (ocf::heartbeat:SAPInstance):   Stopped (disabled)
    

    Start the ASCS instance again on the same node.

    nw1-cl-1:nw1adm 54> sapcontrol -nr 00 -function StartWait 600 2
    

    The enqueue lock of transaction su01 should be lost and the back-end should have been reset. Resource state after the test:

    stonith-sbd     (stonith:external/sbd): Started nw1-cl-1
     Resource Group: g-NW1_ASCS
         fs_NW1_ASCS        (ocf::heartbeat:Filesystem):    Started nw1-cl-1
         nc_NW1_ASCS        (ocf::heartbeat:azure-lb):      Started nw1-cl-1
         vip_NW1_ASCS       (ocf::heartbeat:IPaddr2):       Started nw1-cl-1
         rsc_sap_NW1_ASCS00 (ocf::heartbeat:SAPInstance):   Started nw1-cl-1
     Resource Group: g-NW1_ERS
         fs_NW1_ERS (ocf::heartbeat:Filesystem):    Started nw1-cl-0
         nc_NW1_ERS (ocf::heartbeat:azure-lb):      Started nw1-cl-0
         vip_NW1_ERS        (ocf::heartbeat:IPaddr2):       Started nw1-cl-0
         rsc_sap_NW1_ERS02  (ocf::heartbeat:SAPInstance):   Started nw1-cl-0
    
  7. Kill message server process

    Resource state before starting the test:

    stonith-sbd     (stonith:external/sbd): Started nw1-cl-1
     Resource Group: g-NW1_ASCS
         fs_NW1_ASCS        (ocf::heartbeat:Filesystem):    Started nw1-cl-1
         nc_NW1_ASCS        (ocf::heartbeat:azure-lb):      Started nw1-cl-1
         vip_NW1_ASCS       (ocf::heartbeat:IPaddr2):       Started nw1-cl-1
         rsc_sap_NW1_ASCS00 (ocf::heartbeat:SAPInstance):   Started nw1-cl-1
     Resource Group: g-NW1_ERS
         fs_NW1_ERS (ocf::heartbeat:Filesystem):    Started nw1-cl-0
         nc_NW1_ERS (ocf::heartbeat:azure-lb):      Started nw1-cl-0
         vip_NW1_ERS        (ocf::heartbeat:IPaddr2):       Started nw1-cl-0
         rsc_sap_NW1_ERS02  (ocf::heartbeat:SAPInstance):   Started nw1-cl-0
    

    Run the following commands as root to identify the process of the message server and kill it.

    nw1-cl-1:~ # pgrep -f ms.sapNW1 | xargs kill -9
    

    If you only kill the message server once, it will be restarted by sapstart. If you kill it often enough, Pacemaker will eventually move the ASCS instance to the other node, in case of ENSA1. Run the following commands as root to clean up the resource state of the ASCS and ERS instance after the test.

    nw1-cl-0:~ # crm resource cleanup rsc_sap_NW1_ASCS00
    nw1-cl-0:~ # crm resource cleanup rsc_sap_NW1_ERS02
    

    Resource state after the test:

    stonith-sbd     (stonith:external/sbd): Started nw1-cl-1
     Resource Group: g-NW1_ASCS
         fs_NW1_ASCS        (ocf::heartbeat:Filesystem):    Started nw1-cl-0
         nc_NW1_ASCS        (ocf::heartbeat:azure-lb):      Started nw1-cl-0
         vip_NW1_ASCS       (ocf::heartbeat:IPaddr2):       Started nw1-cl-0
         rsc_sap_NW1_ASCS00 (ocf::heartbeat:SAPInstance):   Started nw1-cl-0
     Resource Group: g-NW1_ERS
         fs_NW1_ERS (ocf::heartbeat:Filesystem):    Started nw1-cl-1
         nc_NW1_ERS (ocf::heartbeat:azure-lb):      Started nw1-cl-1
         vip_NW1_ERS        (ocf::heartbeat:IPaddr2):       Started nw1-cl-1
         rsc_sap_NW1_ERS02  (ocf::heartbeat:SAPInstance):   Started nw1-cl-1
    
  8. Kill enqueue server process

    Resource state before starting the test:

    stonith-sbd     (stonith:external/sbd): Started nw1-cl-1
     Resource Group: g-NW1_ASCS
         fs_NW1_ASCS        (ocf::heartbeat:Filesystem):    Started nw1-cl-0
         nc_NW1_ASCS        (ocf::heartbeat:azure-lb):      Started nw1-cl-0
         vip_NW1_ASCS       (ocf::heartbeat:IPaddr2):       Started nw1-cl-0
         rsc_sap_NW1_ASCS00 (ocf::heartbeat:SAPInstance):   Started nw1-cl-0
     Resource Group: g-NW1_ERS
         fs_NW1_ERS (ocf::heartbeat:Filesystem):    Started nw1-cl-1
         nc_NW1_ERS (ocf::heartbeat:azure-lb):      Started nw1-cl-1
         vip_NW1_ERS        (ocf::heartbeat:IPaddr2):       Started nw1-cl-1
         rsc_sap_NW1_ERS02  (ocf::heartbeat:SAPInstance):   Started nw1-cl-1
    

    Run the following commands as root on the node where the ASCS instance is running to kill the enqueue server.

    nw1-cl-0:~ # 
    #If using ENSA1
    pgrep -f en.sapNW1 | xargs kill -9
    #If using ENSA2
    pgrep -f enq.sapNW1 | xargs kill -9
    

    The ASCS instance should immediately fail over to the other node, in the case of ENSA1. The ERS instance should also fail over after the ASCS instance is started. Run the following commands as root to clean up the resource state of the ASCS and ERS instance after the test.

    nw1-cl-0:~ # crm resource cleanup rsc_sap_NW1_ASCS00
    nw1-cl-0:~ # crm resource cleanup rsc_sap_NW1_ERS02
    

    Resource state after the test:

    stonith-sbd     (stonith:external/sbd): Started nw1-cl-1
     Resource Group: g-NW1_ASCS
         fs_NW1_ASCS        (ocf::heartbeat:Filesystem):    Started nw1-cl-1
         nc_NW1_ASCS        (ocf::heartbeat:azure-lb):      Started nw1-cl-1
         vip_NW1_ASCS       (ocf::heartbeat:IPaddr2):       Started nw1-cl-1
         rsc_sap_NW1_ASCS00 (ocf::heartbeat:SAPInstance):   Started nw1-cl-1
     Resource Group: g-NW1_ERS
         fs_NW1_ERS (ocf::heartbeat:Filesystem):    Started nw1-cl-0
         nc_NW1_ERS (ocf::heartbeat:azure-lb):      Started nw1-cl-0
         vip_NW1_ERS        (ocf::heartbeat:IPaddr2):       Started nw1-cl-0
         rsc_sap_NW1_ERS02  (ocf::heartbeat:SAPInstance):   Started nw1-cl-0
    
  9. Kill enqueue replication server process

    Resource state before starting the test:

    stonith-sbd     (stonith:external/sbd): Started nw1-cl-1
     Resource Group: g-NW1_ASCS
         fs_NW1_ASCS        (ocf::heartbeat:Filesystem):    Started nw1-cl-1
         nc_NW1_ASCS        (ocf::heartbeat:azure-lb):      Started nw1-cl-1
         vip_NW1_ASCS       (ocf::heartbeat:IPaddr2):       Started nw1-cl-1
         rsc_sap_NW1_ASCS00 (ocf::heartbeat:SAPInstance):   Started nw1-cl-1
     Resource Group: g-NW1_ERS
         fs_NW1_ERS (ocf::heartbeat:Filesystem):    Started nw1-cl-0
         nc_NW1_ERS (ocf::heartbeat:azure-lb):      Started nw1-cl-0
         vip_NW1_ERS        (ocf::heartbeat:IPaddr2):       Started nw1-cl-0
         rsc_sap_NW1_ERS02  (ocf::heartbeat:SAPInstance):   Started nw1-cl-0
    

    Run the following command as root on the node where the ERS instance is running to kill the enqueue replication server process.

    nw1-cl-0:~ # pgrep -f er.sapNW1 | xargs kill -9
    

    If you only run the command once, sapstart will restart the process. If you run it often enough, sapstart will not restart the process, and the resource will be in a stopped state. Run the following commands as root to clean up the resource state of the ERS instance after the test.

    nw1-cl-0:~ # crm resource cleanup rsc_sap_NW1_ERS02
    

    Resource state after the test:

    stonith-sbd     (stonith:external/sbd): Started nw1-cl-1
     Resource Group: g-NW1_ASCS
         fs_NW1_ASCS        (ocf::heartbeat:Filesystem):    Started nw1-cl-1
         nc_NW1_ASCS        (ocf::heartbeat:azure-lb):      Started nw1-cl-1
         vip_NW1_ASCS       (ocf::heartbeat:IPaddr2):       Started nw1-cl-1
         rsc_sap_NW1_ASCS00 (ocf::heartbeat:SAPInstance):   Started nw1-cl-1
     Resource Group: g-NW1_ERS
         fs_NW1_ERS (ocf::heartbeat:Filesystem):    Started nw1-cl-0
         nc_NW1_ERS (ocf::heartbeat:azure-lb):      Started nw1-cl-0
         vip_NW1_ERS        (ocf::heartbeat:IPaddr2):       Started nw1-cl-0
         rsc_sap_NW1_ERS02  (ocf::heartbeat:SAPInstance):   Started nw1-cl-0
    
  10. Kill enqueue sapstartsrv process

    Resource state before starting the test:

    stonith-sbd     (stonith:external/sbd): Started nw1-cl-1
     Resource Group: g-NW1_ASCS
         fs_NW1_ASCS        (ocf::heartbeat:Filesystem):    Started nw1-cl-1
         nc_NW1_ASCS        (ocf::heartbeat:azure-lb):      Started nw1-cl-1
         vip_NW1_ASCS       (ocf::heartbeat:IPaddr2):       Started nw1-cl-1
         rsc_sap_NW1_ASCS00 (ocf::heartbeat:SAPInstance):   Started nw1-cl-1
     Resource Group: g-NW1_ERS
         fs_NW1_ERS (ocf::heartbeat:Filesystem):    Started nw1-cl-0
         nc_NW1_ERS (ocf::heartbeat:azure-lb):      Started nw1-cl-0
         vip_NW1_ERS        (ocf::heartbeat:IPaddr2):       Started nw1-cl-0
         rsc_sap_NW1_ERS02  (ocf::heartbeat:SAPInstance):   Started nw1-cl-0
    

    Run the following commands as root on the node where the ASCS is running.

    nw1-cl-1:~ # pgrep -fl ASCS00.*sapstartsrv
    # 59545 sapstartsrv
    
    nw1-cl-1:~ # kill -9 59545
    

    The sapstartsrv process should always be restarted by the Pacemaker resource agent. Resource state after the test:

    stonith-sbd     (stonith:external/sbd): Started nw1-cl-1
     Resource Group: g-NW1_ASCS
         fs_NW1_ASCS        (ocf::heartbeat:Filesystem):    Started nw1-cl-1
         nc_NW1_ASCS        (ocf::heartbeat:azure-lb):      Started nw1-cl-1
         vip_NW1_ASCS       (ocf::heartbeat:IPaddr2):       Started nw1-cl-1
         rsc_sap_NW1_ASCS00 (ocf::heartbeat:SAPInstance):   Started nw1-cl-1
     Resource Group: g-NW1_ERS
         fs_NW1_ERS (ocf::heartbeat:Filesystem):    Started nw1-cl-0
         nc_NW1_ERS (ocf::heartbeat:azure-lb):      Started nw1-cl-0
         vip_NW1_ERS        (ocf::heartbeat:IPaddr2):       Started nw1-cl-0
         rsc_sap_NW1_ERS02  (ocf::heartbeat:SAPInstance):   Started nw1-cl-0
    

Next steps