Azure Virtual Machines HA for SAP NetWeaver on RHEL with Azure NetApp Files for SAP applications

This article describes how to deploy virtual machines (VMs), configure the VMs, install the cluster framework, and install a highly available SAP NetWeaver 7.50 system by using Azure NetApp Files. In the example configurations and installation commands, the ASCS instance is number 00, the ERS instance is number 01, the Primary Application instance (PAS) is 02, and the Application instance (AAS) is 03. The SAP System ID QAS is used.

The database layer isn't covered in detail in this article.

Prerequisites

Read the following SAP Notes and papers first:

• Azure NetApp Files documentation

• SAP Note 1928533, which has:

  • A list of Azure VM sizes that are supported for the deployment of SAP software.
  • Important capacity information for Azure VM sizes.
  • Supported SAP software and operating system (OS) and database combinations.
  • Required SAP kernel version for Windows and Linux on Microsoft Azure.

• SAP Note 2015553 lists prerequisites for SAP-supported SAP software deployments in Azure.

• SAP Note 2002167 has recommended OS settings for Red Hat Enterprise Linux.

• SAP Note 2009879 has SAP HANA Guidelines for Red Hat Enterprise Linux.

• SAP Note 2178632 has detailed information about all monitoring metrics reported for SAP in Azure.

• SAP Note 2191498 has the required SAP Host Agent version for Linux in Azure.

• SAP Note 2243692 has information about SAP licensing on Linux in Azure.

• SAP Note 1999351 has more troubleshooting information for the Azure Enhanced Monitoring Extension for SAP.

• SAP Community WIKI has all required SAP Notes for Linux.

• Azure Virtual Machines planning and implementation for SAP on Linux

• Azure Virtual Machines deployment for SAP on Linux

• Azure Virtual Machines DBMS deployment for SAP on Linux

• SAP NetWeaver in Pacemaker cluster

• General Red Hat Enterprise Linux (RHEL) documentation:

  • High Availability Add-On Overview
  • High Availability Add-On Administration
  • High Availability Add-On Reference
  • Configuring ASCS/ERS for SAP NetWeaver with standalone resources in RHEL 7.5
  • Configure SAP S/4HANA ASCS/ERS with Standalone Enqueue Server 2 (ENSA2) in Pacemaker on RHEL

• Azure-specific RHEL documentation:

  • Support Policies for RHEL High Availability Clusters - Microsoft Azure Virtual Machines as Cluster Members
  • Installing and Configuring a Red Hat Enterprise Linux 7.4 (and later) High-Availability Cluster on Microsoft Azure

• NetApp SAP Applications on Microsoft Azure using Azure NetApp Files

• NetApp NFS Best Practices

Overview

High availability (HA) for SAP NetWeaver central services requires shared storage. Until now to achieve HA on Red Hat Linux, it was necessary to build a separate highly available GlusterFS cluster.

Now it's possible to achieve SAP NetWeaver HA by using shared storage deployed on Azure NetApp Files. Using Azure NetApp Files for shared storage eliminates the need for more GlusterFS clusters. Pacemaker is still needed for HA of the SAP NetWeaver central services (ASCS/SCS).

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 Azure Load Balancer Standard. The configuration here shows a load balancer with a:

• Front-end IP address 192.168.14.9 for ASCS.
• Front-end IP address 192.168.14.10 for ERS.
• Probe port 62000 for ASCS.
• Probe port 62101 for ERS.

Set up the Azure NetApp Files infrastructure

SAP NetWeaver requires shared storage for the transport and profile directory. Before you proceed with the setup for Azure NetApp Files infrastructure, familiarize yourself with the Azure NetApp Files documentation. Check if your selected Azure region offers Azure NetApp Files. For the availability of Azure NetApp Files by Azure region, see Azure NetApp Files availability by Azure region.

Azure NetApp Files are available in several Azure regions.

Deploy Azure NetApp Files resources

The steps assume that you already deployed Azure Virtual Network. The Azure NetApp Files resources and the VMs, where the Azure NetApp Files resources will be mounted, must be deployed in the same Azure virtual network or in peered Azure virtual networks.

1. Create the Azure NetApp Files account in the selected Azure region by following the instructions to create an Azure NetApp Files account.

2. Set up an Azure NetApp Files capacity pool by following the instructions on how to set up an Azure NetApp Files capacity pool. The SAP NetWeaver architecture presented in this article uses a single Azure NetApp Files capacity pool, Premium SKU. We recommend the Azure NetApp Files Premium SKU for the SAP NetWeaver application workload on Azure.

3. Delegate a subnet to Azure NetApp Files as described in the instructions on how to delegate a subnet to Azure NetApp Files.

4. Deploy Azure NetApp Files volumes by following the instructions to create a volume for Azure NetApp Files. Deploy the volumes in the designated Azure NetApp Files subnet. The IP addresses of the Azure NetApp volumes are assigned automatically. The Azure NetApp Files resources and the Azure VMs must be in the same Azure virtual network or in peered Azure virtual networks. In this example, we use two Azure NetApp Files volumes: sapQAS and transSAP. The file paths that are mounted to the corresponding mount points are /usrsapqas/sapmntQAS and /usrsapqas/usrsapQASsys.

   1. Volume sapQAS (nfs://192.168.24.5/usrsapqas/sapmntQAS)
   2. Volume sapQAS (nfs://192.168.24.5/usrsapqas/usrsapQASascs)
   3. Volume sapQAS (nfs://192.168.24.5/usrsapqas/usrsapQASsys)
   4. Volume sapQAS (nfs://192.168.24.5/usrsapqas/usrsapQASers)
   5. Volume transSAP (nfs://192.168.24.4/transSAP)
   6. Volume sapQAS (nfs://192.168.24.5/usrsapqas/usrsapQASpas)
   7. Volume sapQAS (nfs://192.168.24.5/usrsapqas/usrsapQASaas)

In this example, we used Azure NetApp Files for all SAP NetWeaver file systems to demonstrate how you can use Azure NetApp Files. The SAP file systems that don't need to be mounted via NFS can also be deployed as Azure disk storage. In this example, a-e must be on Azure NetApp Files and f-g (that is, /usr/sap/QAS/D02 and /usr/sap/QAS/D03) could be deployed as Azure disk storage.

Important considerations

When you consider Azure NetApp Files for the SAP NetWeaver on RHEL HA architecture, be aware of the following important considerations:

• The minimum capacity pool is 4 TiB. You can increase the capacity pool size in 1-TiB increments.
• The minimum volume is 100 GiB.
• Azure NetApp Files and all VMs, where Azure NetApp Files volumes will be mounted, must be in the same Azure virtual network or in peered virtual networks in the same region. Azure NetApp Files access over virtual network peering in the same region is supported now. Azure NetApp Files access over global peering isn't supported yet.
• The selected virtual network must have a subnet delegated to Azure NetApp Files.
• The throughput and performance characteristics of an Azure NetApp Files volume is a function of the volume quota and service level. For more information, see Service level for Azure NetApp Files. When you size the SAP Azure NetApp volumes, make sure that the resulting throughput meets the application requirements.
• Azure NetApp Files offers export policy. You can control the allowed clients and the access type (like Read/Write and Read Only).
• The Azure NetApp Files feature isn't zone aware yet. Currently, the Azure NetApp Files feature isn't deployed in all availability zones in an Azure region. Be aware of the potential latency implications in some Azure regions.
• You can deploy Azure NetApp Files volumes as NFSv3 or NFSv4.1 volumes. Both protocols are supported for the SAP application layer (ASCS/ERS, SAP application servers).

Prepare the infrastructure

Azure Marketplace contains images qualified for SAP with the High Availability add-on, which you can use to deploy new VMs by using various versions of Red Hat.

Deploy Linux VMs manually via the Azure portal

This document assumes that you already deployed an Azure virtual network, subnet, and resource group.

Deploy VMs for SAP ASCS, ERS and Application servers. Choose a suitable RHEL image that's supported for the SAP system. You can deploy a 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.

Azure portal

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.

Azure CLI

To create Azure standard load balancer for high availability setup of SAP system using Azure CLI, follow below steps.

# Create the load balancer resource and another frontend IP resource for ERS. Allocation of private IP address is dynamic using below command. If you want to pass static IP address, include parameter --private-ip-address.
az network lb create -g MyResourceGroup -n MyLB --sku Standard --vnet-name MyVMsVirtualNetwork --subnet MyVMsSubnet --backend-pool-name MyBackendPool --frontend-ip-name MyASCSFrontendIpName
az network lb frontend-ip create -g MyResourceGroup --lb-name MyLB -n MyERSFrontendIpName --vnet-name MyVMsVirtualNetwork --subnet MyVMsSubnet

# Create the health probe for ASCS and ERS
az network lb probe create -g MyResourceGroup --lb-name MyLB -n MyASCSHealthProbe --protocol tcp --port MyASCSHealthProbePort --interval 5 --probe-threshold 2
az network lb probe create -g MyResourceGroup --lb-name MyLB -n MyERSHealthProbe --protocol tcp --port MyERSHealthProbePort --interval 5 --probe-threshold 2
 
# Create load balancing rule for ASCS and ERS
az network lb rule create -g MyResourceGroup --lb-name MyLB -n MyASCSRuleName --protocol All --frontend-ip-name MyASCSFrontendIpName --frontend-port 0 --backend-pool-name MyBackendPool --backend-port 0 --probe-name MyASCSHealthProbe --idle-timeout-in-minutes 30 --enable-floating-ip 
az network lb rule create -g MyResourceGroup --lb-name MyLB -n MyERSRuleName --protocol All --frontend-ip-name MyERSFrontendIpName --frontend-port 0 --backend-pool-name MyBackendPool --backend-port 0 --probe-name MyERSHealthProbe --idle-timeout-in-minutes 30 --enable-floating-ip  

# Add ASCS and ERS VMs in backend pool
az network nic ip-config address-pool add --address-pool MyBackendPool --ip-config-name ASCSVmIpConfigName --nic-name ASCSVmNicName -g MyResourceGroup --lb-name MyLB
az network nic ip-config address-pool add --address-pool MyBackendPool --ip-config-name ERSVmIpConfigName --nic-name ERSVmNicName -g MyResourceGroup --lb-name MyLB

Expand to view full CLI code

# Define variables for Resource Group, ASCS/ERS VMs.

rg_name="resourcegroup-name"
vm1_name="ascs-vm-name"
vm2_name="ers-vm-name"

# Define variables for the load balancer that will be use in the creation of the load balancer resource.

lb_name="sap-ci-sid-ilb"
bkp_name="ascs-ers-backendpool"
ascs_fip_name="ascs-frontendip"
ers_fip_name="ers-frontendip"

ascs_hp_name="ascs-healthprobe"
ascs_hp_port="62000"
ers_hp_name="ers-healthprobe"
ers_hp_port="62101"

ascs_rule_name="ascs-lb-rule"
ers_rule_name="ers-lb-rule"
 
# Command to get VMs network information like primary NIC name, primary IP configuration name, virtual network name, and subnet name.
 
vm1_primary_nic=$(az vm nic list -g $rg_name --vm-name $vm1_name --query "[?primary == \`true\`].{id:id} || [?primary == \`null\`].{id:id}" -o tsv)
vm1_nic_name=$(basename $vm1_primary_nic)
vm1_ipconfig=$(az network nic ip-config list -g $rg_name --nic-name $vm1_nic_name --query "[?primary == \`true\`].name" -o tsv)
 
vm2_primary_nic=$(az vm nic list -g $rg_name --vm-name $vm2_name --query "[?primary == \`true\`].{id:id} || [?primary == \`null\`].{id:id}" -o tsv)
vm2_nic_name=$(basename $vm2_primary_nic)
vm2_ipconfig=$(az network nic ip-config list -g $rg_name --nic-name $vm2_nic_name --query "[?primary == \`true\`].name" -o tsv)
 
vnet_subnet_id=$(az network nic show -g $rg_name -n $vm1_nic_name --query ipConfigurations[0].subnet.id -o tsv)
vnet_name=$(basename $(dirname $(dirname $vnet_subnet_id)))
subnet_name=$(basename $vnet_subnet_id)
 
# Create the load balancer resource and another frontend IP resource for ERS.
# Allocation of private IP address is dynamic using below command. If you want to pass static IP address, include parameter --private-ip-address. 
  
az network lb create -g $rg_name -n $lb_name --sku Standard --vnet-name $vnet_name --subnet $subnet_name --backend-pool-name $bkp_name --frontend-ip-name $ascs_fip_name
az network lb frontend-ip create -g $rg_name --lb-name $lb_name -n $ers_fip_name --vnet-name $vnet_name --subnet $subnet_name
 
# Create the health probe for ASCS and ERS
 
az network lb probe create -g $rg_name --lb-name $lb_name -n $ascs_hp_name --protocol tcp --port $ascs_hp_port --interval 5 --probe-threshold 2
az network lb probe create -g $rg_name --lb-name $lb_name -n $ers_hp_name --protocol tcp --port $ers_hp_port --interval 5 --probe-threshold 2
 
# Create load balancing rule for ASCS and ERS
  
az network lb rule create -g $rg_name --lb-name $lb_name -n  $ascs_rule_name --protocol All --frontend-ip-name $ascs_fip_name --frontend-port 0 --backend-pool-name $bkp_name --backend-port 0 --probe-name $ascs_hp_name --idle-timeout-in-minutes 30 --enable-floating-ip 
az network lb rule create -g $rg_name --lb-name $lb_name -n  $ers_rule_name --protocol All --frontend-ip-name $ers_fip_name --frontend-port 0 --backend-pool-name $bkp_name --backend-port 0 --probe-name $ers_hp_name --idle-timeout-in-minutes 30 --enable-floating-ip 
 
# Add ASCS and ERS VMs in backend pool
 
az network nic ip-config address-pool add --address-pool $bkp_name --ip-config-name $vm1_ipconfig --nic-name $vm1_nic_name -g $rg_name --lb-name $lb_name
az network nic ip-config address-pool add --address-pool $bkp_name --ip-config-name $vm2_ipconfig --nic-name $vm2_nic_name -g $rg_name --lb-name $lb_name

# [OPTIONAL] Change the assignment of frontend IP address from dynamic to static
afip=$(az network lb frontend-ip show --lb-name $lb_name -g $rg_name -n $ascs_fip_name --query "{privateIPAddress:privateIPAddress}" -o tsv)
az network lb frontend-ip update --lb-name $lb_name -g $rg_name -n $ascs_fip_name --private-ip-address $afip

efip=$(az network lb frontend-ip show --lb-name $lb_name -g $rg_name -n $ers_fip_name --query "{privateIPAddress:privateIPAddress}" -o tsv)
az network lb frontend-ip update --lb-name $lb_name -g $rg_name -n $ers_fip_name --private-ip-address $efip

PowerShell

To create Azure standard load balancer for high availability setup of SAP system using Azure PowerShell, follow below steps.

# Create frontend IP configurations
$ascs_fip = New-AzLoadBalancerFrontendIpConfig -Name MyASCSFrontendIpName -SubnetId MyASCSSubnetName
$ers_fip = New-AzLoadBalancerFrontendIpConfig -Name MyERSFrontendIpName -SubnetId MyERSSubnetName

# Create backend pool
$bePool = New-AzLoadBalancerBackendAddressPoolConfig -Name MyBackendPool

# Create health probes for ASCS and ERS
$ascs_healthprobe = New-AzLoadBalancerProbeConfig -Name MyASCSHealthProbe -Protocol 'tcp' -Port MyASCSHealthProbePort -IntervalInSeconds 5 -ProbeThreshold 2 -ProbeCount 1
$ers_healthprobe = New-AzLoadBalancerProbeConfig -Name $ers_hp_name -Protocol 'tcp' -Port MyASCSHealthProbePort -IntervalInSeconds 5 -ProbeThreshold 2 -ProbeCount 1

# Create load balancing rules for ASCS and ERS
$ascs_rule = New-AzLoadBalancerRuleConfig -Name MyASCSRuleName -Probe $ascs_healthprobe -Protocol 'All' -IdleTimeoutInMinutes 30 -FrontendIpConfiguration $ascs_fip -BackendAddressPool $bePool -EnableFloatingIP
$ers_rule = New-AzLoadBalancerRuleConfig -Name MyERSRuleName -Probe $ers_healthprobe -Protocol 'All' -IdleTimeoutInMinutes 30 -FrontendIpConfiguration $ers_fip -BackendAddressPool $bePool -EnableFloatingIP

# Create the load balancer resource
$lb = New-AzLoadBalancer -ResourceGroupName MyResourceGroup -Name MyLB -Location MyRegion -Sku 'Standard' -FrontendIpConfiguration $ascs_fip, $ers_fip -BackendAddressPool $bePool -LoadBalancingRule $ascs_rule, $ers_rule -Probe $ascs_healthprobe, $ers_healthprobe

Expand to view full PowerShell code

# Define variables for Resource Group, and Database VMs.

$rg_name = 'resourcegroup-name'
$vm1_name = 'ascs-vm-name'
$vm2_name = 'ers-vm-name'

# Define variables for the load balancer that will be utilized in the creation of the load balancer resource.

$lb_name = 'sap-ci-sid-ilb'
$bkp_name = 'ascs-ers-backendpool'
$ascs_fip_name = 'ascs-frontendip'
$ers_fip_name = 'ers-frontendip'
 
$ascs_hp_name = 'ascs-healthprobe'
$ascs_hp_port = '62000'
$ers_hp_name = 'ers-healthprobe'
$ers_hp_port = '62101'
 
$ascs_rule_name = 'ascs-lb-rule'
$ers_rule_name = 'ers-lb-rule'
 
# Command to get VMs network information like NIC name, IP configuration name, Virtual Network name, and Subnet 
 
$vm1 = Get-AzVM -ResourceGroupName $rg_name -Name $vm1_name
$vm1_primarynic = $vm1.NetworkProfile.NetworkInterfaces | Where-Object {($_.Primary -eq "True") -or ($_.Primary -eq $null)}
$vm1_nic_name = $vm1_primarynic.Id.Split('/')[-1]
 
$vm1_nic_info = Get-AzNetworkInterface -Name $vm1_nic_name -ResourceGroupName $rg_name
$vm1_primaryip = $vm1_nic_info.IpConfigurations | Where-Object -Property Primary -EQ -Value "True"
$vm1_ipconfig_name = ($vm1_primaryip).Name
 
$vm2 = Get-AzVM -ResourceGroupName $rg_name -Name $vm2_name
$vm2_primarynic = $vm2.NetworkProfile.NetworkInterfaces | Where-Object {($_.Primary -eq "True") -or ($_.Primary -eq $null)}
$vm2_nic_name = $vm2_primarynic.Id.Split('/')[-1]
 
$vm2_nic_info = Get-AzNetworkInterface -Name $vm2_nic_name -ResourceGroupName $rg_name
$vm2_primaryip = $vm2_nic_info.IpConfigurations | Where-Object -Property Primary -EQ -Value "True"
$vm2_ipconfig_name = ($vm2_primaryip).Name
 
$vnet_name = $vm1_primaryip.Subnet.Id.Split('/')[-3]
$subnet_name = $vm1_primaryip.Subnet.Id.Split('/')[-1]
$location = $vm1.Location
 
# Create frontend IP resource for ASCS and ERS.
# Allocation of private IP address is dynamic using below command. If you want to pass static IP address, include parameter -PrivateIpAddress
 
$ascs_lb_fip = @{
    Name = $ascs_fip_name
    SubnetId = $vm1_primaryip.Subnet.Id
}
$ascs_fip = New-AzLoadBalancerFrontendIpConfig @ascs_lb_fip
 
$ers_lb_fip = @{
    Name = $ers_fip_name
    SubnetId = $vm2_primaryip.Subnet.Id
}
$ers_fip = New-AzLoadBalancerFrontendIpConfig @ers_lb_fip

# Create backend pool
 
$bepool = New-AzLoadBalancerBackendAddressPoolConfig -Name $bkp_name

# Create the health probe for ASCS and ERS
 
$ascs_probe = @{
    Name = $ascs_hp_name
    Protocol = 'tcp'
    Port = $ascs_hp_port
    IntervalInSeconds = '5'
    ProbeThreshold = '2'
    ProbeCount = '1'
}
$ascs_healthprobe = New-AzLoadBalancerProbeConfig @ascs_probe
    
$ers_probe = @{
    Name = $ers_hp_name
    Protocol = 'tcp'
    Port = $ers_hp_port
    IntervalInSeconds = '5'
    ProbeThreshold = '2'
    ProbeCount = '1'
}
$ers_healthprobe = New-AzLoadBalancerProbeConfig @ers_probe

# Create load balancing rule for ASCS and ERS
 
$ascs_lbrule = @{
    Name = $ascs_rule_name
    Probe = $ascs_healthprobe
    Protocol = 'All'
    IdleTimeoutInMinutes = '30'
    FrontendIpConfiguration = $ascs_fip
    BackendAddressPool = $bePool 
} 
$ascs_rule = New-AzLoadBalancerRuleConfig @ascs_lbrule -EnableFloatingIP 
 
$ers_lbrule = @{
    Name = $ers_rule_name
    Probe = $ers_healthprobe
    Protocol = 'All'
    IdleTimeoutInMinutes = '30'
    FrontendIpConfiguration = $ers_fip
    BackendAddressPool = $bePool 
} 
$ers_rule = New-AzLoadBalancerRuleConfig @ers_lbrule -EnableFloatingIP

# Create the load balancer resource
 
$loadbalancer = @{
    ResourceGroupName = $rg_name
    Name = $lb_name
    Location = $location
    Sku = 'Standard'
    FrontendIpConfiguration = $ascs_fip,$ers_fip
    BackendAddressPool = $bePool 
    LoadBalancingRule = $ascs_rule,$ers_rule
    Probe = $ascs_healthprobe,$ers_healthprobe 
} 
$lb = New-AzLoadBalancer @loadbalancer

# Add ASCS and ERS VMs in backend pool of load balanceer
 
$vm1_primaryip.LoadBalancerBackendAddressPools.Add($lb.BackendAddressPools[0])
$vm2_primaryip.LoadBalancerBackendAddressPools.Add($lb.BackendAddressPools[0])
$vm1_nic_info | Set-AzNetworkInterface
$vm2_nic_info | Set-AzNetworkInterface

Note

When VMs without public IP addresses are placed in the back-end pool of an internal (no public IP address) standard load balancer, there's no outbound internet connectivity unless more configuration is performed to allow routing to public endpoints. For more information on how to achieve outbound connectivity, see Public endpoint connectivity for VMs by using Azure Standard Load Balancer in SAP high-availability scenarios.

Important

Don't enable TCP timestamps on Azure VMs placed behind Azure Load Balancer. Enabling TCP timestamps could cause the health probes to fail. Set the parameter net.ipv4.tcp_timestamps to 0. For more information, see Load Balancer health probes.

Disable ID mapping (if you use NFSv4.1)

The instructions in this section are only applicable if you're using Azure NetApp Files volumes with the NFSv4.1 protocol. Perform the configuration on all VMs where Azure NetApp Files NFSv4.1 volumes will be mounted.

1. Verify the NFS domain setting. Make sure that the domain is configured as the default Azure NetApp Files domain, that is, defaultv4iddomain.com, and the mapping is set to nobody.

   Important

   Make sure to set the NFS domain in /etc/idmapd.conf on the VM to match the default domain configuration on Azure NetApp Files: defaultv4iddomain.com. If there's a mismatch between the domain configuration on the NFS client (that is, the VM) and the NFS server (that is, the Azure NetApp configuration), then the permissions for files on Azure NetApp volumes that are mounted on the VMs display as nobody.

   sudo cat /etc/idmapd.conf
   
   # Example
   [General]
   Domain = defaultv4iddomain.com
   [Mapping]
   Nobody-User = nobody
   Nobody-Group = nobody
   

The following [A] prefix applies to both PAS and AAS.

1. [A] Verify nfs4_disable_idmapping. It should be set to Y. To create the directory structure where nfs4_disable_idmapping is located, run the mount command. You won't be able to manually create the directory under /sys/modules because access is reserved for the kernel and drivers.

   # Check nfs4_disable_idmapping 
   cat /sys/module/nfs/parameters/nfs4_disable_idmapping
   
   # If you need to set nfs4_disable_idmapping to Y
   mkdir /mnt/tmp
   mount 192.168.24.5:/sapQAS
   umount  /mnt/tmp
   echo "Y" > /sys/module/nfs/parameters/nfs4_disable_idmapping
   
   # Make the configuration permanent
   echo "options nfs nfs4_disable_idmapping=Y" >> /etc/modprobe.d/nfs.conf
   

Set up (A)SCS

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

Create a Pacemaker cluster

Follow the steps in Set up Pacemaker on Red Hat Enterprise Linux in Azure to create a basic Pacemaker cluster for this (A)SCS server.

Prepare for the SAP NetWeaver installation

The following items are prefixed with either:

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

1. [A] Set up hostname resolution.

   You can either use a DNS server or modify the /etc/hosts file 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 cluster node 1
   192.168.14.5    anftstsapcl1
   # IP address of cluster node 2
   192.168.14.6     anftstsapcl2
   # IP address of the load balancer frontend configuration for SAP Netweaver ASCS
   192.168.14.9    anftstsapvh
   # IP address of the load balancer frontend configuration for SAP Netweaver ERS
   192.168.14.10    anftstsapers
   

2. [1] Create SAP directories in the Azure NetApp Files volume. Mount the Azure NetApp Files volume temporarily on one of the VMs and create the SAP directories (file paths).

   # mount temporarily the volume
   sudo mkdir -p /saptmp
   
   # If using NFSv3
   sudo mount -t nfs -o rw,hard,rsize=65536,wsize=65536,nfsvers=3,tcp 192.168.24.5:/sapQAS /saptmp
   
   # If using NFSv4.1
   sudo mount -t nfs -o rw,hard,rsize=65536,wsize=65536,nfsvers=4.1,sec=sys,tcp 192.168.24.5:/sapQAS /saptmp
   
   # create the SAP directories
   sudo cd /saptmp
   sudo mkdir -p sapmntQAS
   sudo mkdir -p usrsapQASascs
   sudo mkdir -p usrsapQASers
   sudo mkdir -p usrsapQASsys
   sudo mkdir -p usrsapQASpas
   sudo mkdir -p usrsapQASaas
   
   # unmount the volume and delete the temporary directory
   sudo cd ..
   sudo umount /saptmp
   sudo rmdir /saptmp
   

3. [A] Create the shared directories.

   sudo mkdir -p /sapmnt/QAS
   sudo mkdir -p /usr/sap/trans
   sudo mkdir -p /usr/sap/QAS/SYS
   sudo mkdir -p /usr/sap/QAS/ASCS00
   sudo mkdir -p /usr/sap/QAS/ERS01
   
   sudo chattr +i /sapmnt/QAS
   sudo chattr +i /usr/sap/trans
   sudo chattr +i /usr/sap/QAS/SYS
   sudo chattr +i /usr/sap/QAS/ASCS00
   sudo chattr +i /usr/sap/QAS/ERS01
   

4. [A] Install the NFS client and other requirements.

   sudo yum -y install nfs-utils resource-agents resource-agents-sap
   

5. [A] Check the version of resource-agents-sap.

   Make sure that the version of the installed resource-agents-sap package is at least 3.9.5-124.el7.

   sudo yum info resource-agents-sap
   
   # Loaded plugins: langpacks, product-id, search-disabled-repos
   # Repodata is over 2 weeks old. Install yum-cron? Or run: yum makecache fast
   # Installed Packages
   # Name        : resource-agents-sap
   # Arch        : x86_64
   # Version     : 3.9.5
   # Release     : 124.el7
   # Size        : 100 k
   # Repo        : installed
   # From repo   : rhel-sap-for-rhel-7-server-rpms
   # Summary     : SAP cluster resource agents and connector script
   # URL         : https://github.com/ClusterLabs/resource-agents
   # License     : GPLv2+
   # Description : The SAP resource agents and connector script interface with
   #          : Pacemaker to allow SAP instances to be managed in a cluster
   #          : environment.
   

6. [A] Add mount entries.

   If you use NFSv3:

   sudo vi /etc/fstab
   
   # Add the following lines to fstab, save and exit
   192.168.24.5:/sapQAS/sapmntQAS /sapmnt/QAS nfs rw,hard,rsize=65536,wsize=65536,nfsvers=3
   192.168.24.5:/sapQAS/usrsapQASsys /usr/sap/QAS/SYS nfs rw,hard,rsize=65536,wsize=65536,nfsvers=3
   192.168.24.4:/transSAP /usr/sap/trans nfs rw,hard,rsize=65536,wsize=65536,nfsvers=3
   

   If you use NFSv4.1:

   sudo vi /etc/fstab
   
   # Add the following lines to fstab, save and exit
   192.168.24.5:/sapQAS/sapmntQAS /sapmnt/QAS nfs rw,hard,rsize=65536,wsize=65536,nfsvers=4.1,sec=sys
   192.168.24.5:/sapQAS/usrsapQASsys /usr/sap/QAS/SYS nfs rw,hard,rsize=65536,wsize=65536,nfsvers=4.1,sec=sys
   192.168.24.4:/transSAP /usr/sap/trans nfs rw,hard,rsize=65536,wsize=65536,nfsvers=4.1,sec=sys
   

   Note

   Make sure to match the NFS protocol version of the Azure NetApp Files volumes when you mount the volumes. If the Azure NetApp Files volumes are created as NFSv3 volumes, use the corresponding NFSv3 configuration. If the Azure NetApp Files volumes are created as NFSv4.1 volumes, follow the instructions to disable ID mapping and make sure to use the corresponding NFSv4.1 configuration. In this example, the Azure NetApp Files volumes were created as NFSv3 volumes.

   Mount the new shares.

   sudo mount -a  
   

7. [A] Configure the 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 VM 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
   

8. [A] Perform RHEL OS configuration.

   Based on the RHEL version, perform the configuration mentioned in SAP Note 2002167, 2772999, or 3108316.

Install SAP NetWeaver ASCS/ERS

1. [1] Configure cluster default properties.

   pcs resource defaults resource-stickiness=1
   pcs resource defaults migration-threshold=3
   

2. [1] Create a virtual IP resource and health probe for the ASCS instance.

   sudo pcs node standby anftstsapcl2
   
   # If using NFSv3
   sudo pcs resource create fs_QAS_ASCS Filesystem device='192.168.24.5:/sapQAS/usrsapQASascs' \
     directory='/usr/sap/QAS/ASCS00' 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-QAS_ASCS
   
   # If using NFSv4.1
   sudo pcs resource create fs_QAS_ASCS Filesystem device='192.168.24.5:/sapQAS/usrsapQASascs' \
     directory='/usr/sap/QAS/ASCS00' fstype='nfs' force_unmount=safe options='sec=sys,nfsvers=4.1' \
     op start interval=0 timeout=60 op stop interval=0 timeout=120 op monitor interval=200 timeout=105 \
     --group g-QAS_ASCS
   
   sudo pcs resource create vip_QAS_ASCS IPaddr2 \
     ip=192.168.14.9 \
     --group g-QAS_ASCS
   
   sudo pcs resource create nc_QAS_ASCS azure-lb port=62000 \
     --group g-QAS_ASCS
   

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

   sudo pcs status
   
   # Node anftstsapcl2: standby
   # Online: [ anftstsapcl1 ]
   #
   # Full list of resources:
   #
   # rsc_st_azure    (stonith:fence_azure_arm):      Started anftstsapcl1
   #  Resource Group: g-QAS_ASCS
   #      fs_QAS_ASCS        (ocf::heartbeat:Filesystem):    Started anftstsapcl1
   #      nc_QAS_ASCS        (ocf::heartbeat:azure-lb):      Started anftstsapcl1
   #      vip_QAS_ASCS       (ocf::heartbeat:IPaddr2):       Started anftstsapcl1
   

3. [1] Install SAP NetWeaver ASCS.

   Install SAP NetWeaver ASCS as the root on the first node by using a virtual hostname that maps to the IP address of the load balancer front-end configuration for the ASCS, for example, anftstsapvh, 192.168.14.9, 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 nonroot user to connect to sapinst.

   # 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/QAS/ASCS00, try setting the owner and group of the ASCS00 folder and retry.

   sudo chown qasadm /usr/sap/QAS/ASCS00
   sudo chgrp sapsys /usr/sap/QAS/ASCS00
   

4. [1] Create a virtual IP resource and health probe for the ERS instance.

   sudo pcs node unstandby anftstsapcl2
   sudo pcs node standby anftstsapcl1
   
   # If using NFSv3
   sudo pcs resource create fs_QAS_AERS Filesystem device='192.168.24.5:/sapQAS/usrsapQASers' \
     directory='/usr/sap/QAS/ERS01' 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-QAS_AERS
   
   # If using NFSv4.1
   sudo pcs resource create fs_QAS_AERS Filesystem device='192.168.24.5:/sapQAS/usrsapQASers' \
     directory='/usr/sap/QAS/ERS01' fstype='nfs' force_unmount=safe options='sec=sys,nfsvers=4.1' \
     op start interval=0 timeout=60 op stop interval=0 timeout=120 op monitor interval=200 timeout=105 \
    --group g-QAS_AERS
   
   sudo pcs resource create vip_QAS_AERS IPaddr2 \
     ip=192.168.14.10 \
    --group g-QAS_AERS
   
   sudo pcs resource create nc_QAS_AERS azure-lb port=62101 \
    --group g-QAS_AERS
   

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

   sudo pcs status
   
   # Node anftstsapcl1: standby
   # Online: [ anftstsapcl2 ]
   #
   # Full list of resources:
   #
   # rsc_st_azure    (stonith:fence_azure_arm):      Started anftstsapcl2
   #  Resource Group: g-QAS_ASCS
   #      fs_QAS_ASCS        (ocf::heartbeat:Filesystem):    Started anftstsapcl2
   #      nc_QAS_ASCS        (ocf::heartbeat:azure-lb):      Started anftstsapcl2<
   #      vip_QAS_ASCS       (ocf::heartbeat:IPaddr2):       Started anftstsapcl2
   #  Resource Group: g-QAS_AERS
   #      fs_QAS_AERS        (ocf::heartbeat:Filesystem):    Started anftstsapcl2
   #      nc_QAS_AERS        (ocf::heartbeat:azure-lb):      Started anftstsapcl2
   #      vip_QAS_AERS       (ocf::heartbeat:IPaddr2):       Started anftstsapcl2
   

5. [2] Install SAP NetWeaver ERS.

   Install SAP NetWeaver ERS as the root on the second node by using a virtual hostname that maps to the IP address of the load balancer front-end configuration for the ERS, for example, anftstsapers, 192.168.14.10, and the instance number that you used for the probe of the load balancer, for example, 01.

   You can use the sapinst parameter SAPINST_REMOTE_ACCESS_USER to allow a nonroot user to connect to sapinst.

   # 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/QAS/ERS01, try setting the owner and group of the ERS01 folder and retry.

   sudo chown qaadm /usr/sap/QAS/ERS01
   sudo chgrp sapsys /usr/sap/QAS/ERS01
   

6. [1] Adapt the ASCS/SCS and ERS instance profiles.

   • ASCS/SCS profile

     sudo vi /sapmnt/QAS/profile/QAS_ASCS00_anftstsapvh
     
     # 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/QAS/profile/QAS_ERS01_anftstsapers
     
     # 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
     

7. [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 action, set a parameter in the SAP NetWeaver ASCS/SCS profile, if you use ENSA1, and change the Linux system keepalive settings on all SAP servers for both ENSA1/ENSA2. For more information, see SAP Note 1410736.

   # Change the Linux system configuration
   sudo sysctl net.ipv4.tcp_keepalive_time=300
   

8. [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 the /usr/sap/sapservices file.

   sudo vi /usr/sap/sapservices
   
   # Depending on whether the SAP Startup framework is integrated with systemd, you will observe one of the two entries on the ASCS node. You should comment out the line(s). 
   # LD_LIBRARY_PATH=/usr/sap/QAS/ASCS00/exe:$LD_LIBRARY_PATH; export LD_LIBRARY_PATH; /usr/sap/QAS/ASCS00/exe/sapstartsrv pf=/usr/sap/QAS/SYS/profile/QAS_ASCS00_anftstsapvh -D -u qasadm
   # systemctl --no-ask-password start SAPQAS_00 # sapstartsrv pf=/usr/sap/QAS/SYS/profile/QAS_ASCS00_anftstsapvh
   
   # Depending on whether the SAP Startup framework is integrated with systemd, you will observe one of the two entries on the ASCS node. You should comment out the line(s). 
   # LD_LIBRARY_PATH=/usr/sap/QAS/ERS01/exe:$LD_LIBRARY_PATH; export LD_LIBRARY_PATH; /usr/sap/QAS/ERS01/exe/sapstartsrv pf=/usr/sap/QAS/ERS01/profile/QAS_ERS01_anftstsapers -D -u qasadm
   # systemctl --no-ask-password start SAPQAS_01 # sapstartsrv pf=/usr/sap/QAS/ERS01/profile/QAS_ERS01_anftstsapers
   

   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.

9. [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 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 as shown here:

   ENSA1

   sudo pcs property set maintenance-mode=true
   
   # If using NFSv3
   sudo pcs resource create rsc_sap_QAS_ASCS00 SAPInstance \
   InstanceName=QAS_ASCS00_anftstsapvh START_PROFILE="/sapmnt/QAS/profile/QAS_ASCS00_anftstsapvh" \
   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-QAS_ASCS
   
   # If using NFSv4.1
   sudo pcs resource create rsc_sap_QAS_ASCS00 SAPInstance \
   InstanceName=QAS_ASCS00_anftstsapvh START_PROFILE="/sapmnt/QAS/profile/QAS_ASCS00_anftstsapvh" \
   AUTOMATIC_RECOVER=false \
   meta resource-stickiness=5000 migration-threshold=1 failure-timeout=60 \
   op monitor interval=20 on-fail=restart timeout=105 \
   op start interval=0 timeout=600 op stop interval=0 timeout=600 \
   --group g-QAS_ASCS
   
   sudo pcs resource meta g-QAS_ASCS resource-stickiness=3000
   
   # If using NFSv3
   sudo pcs resource create rsc_sap_QAS_ERS01 SAPInstance \
   InstanceName=QAS_ERS01_anftstsapers START_PROFILE="/sapmnt/QAS/profile/QAS_ERS01_anftstsapers" \
   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-QAS_AERS
   
   # If using NFSv4.1
   sudo pcs resource create rsc_sap_QAS_ERS01 SAPInstance \
   InstanceName=QAS_ERS01_anftstsapers START_PROFILE="/sapmnt/QAS/profile/QAS_ERS01_anftstsapers" \
   AUTOMATIC_RECOVER=false IS_ERS=true \
   op monitor interval=20 on-fail=restart timeout=105 op start interval=0 timeout=600 op stop interval=0 timeout=600 \
   --group g-QAS_AERS
   
   sudo pcs constraint colocation add g-QAS_AERS with g-QAS_ASCS -5000
   sudo pcs constraint location rsc_sap_QAS_ASCS00 rule score=2000 runs_ers_QAS eq 1
   sudo pcs constraint order start g-QAS_ASCS then stop g-QAS_AERS kind=Optional symmetrical=false
   
   sudo pcs node unstandby anftstsapcl1
   sudo pcs property set maintenance-mode=false
   

   ENSA2

   sudo pcs property set maintenance-mode=true
   
   # If using NFSv3
   sudo pcs resource create rsc_sap_QAS_ASCS00 SAPInstance \
   InstanceName=QAS_ASCS00_anftstsapvh START_PROFILE="/sapmnt/QAS/profile/QAS_ASCS00_anftstsapvh" \
   AUTOMATIC_RECOVER=false \
   meta resource-stickiness=5000 \
   op monitor interval=20 on-fail=restart timeout=60 \
   op start interval=0 timeout=600 op stop interval=0 timeout=600 \
   --group g-QAS_ASCS
   
   # If using NFSv4.1
   sudo pcs resource create rsc_sap_QAS_ASCS00 SAPInstance \
   InstanceName=QAS_ASCS00_anftstsapvh START_PROFILE="/sapmnt/QAS/profile/QAS_ASCS00_anftstsapvh" \
   AUTOMATIC_RECOVER=false \
   meta resource-stickiness=5000 \
   op monitor interval=20 on-fail=restart timeout=105 \
   op start interval=0 timeout=600 op stop interval=0 timeout=600 \
   --group g-QAS_ASCS
   
   sudo pcs resource meta g-QAS_ASCS resource-stickiness=3000
   
   # If using NFSv3
   sudo pcs resource create rsc_sap_QAS_ERS01 SAPInstance \
   InstanceName=QAS_ERS01_anftstsapers START_PROFILE="/sapmnt/QAS/profile/QAS_ERS01_anftstsapers" \
   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-QAS_AERS
   
   # If using NFSv4.1
   sudo pcs resource create rsc_sap_QAS_ERS01 SAPInstance \
   InstanceName=QAS_ERS01_anftstsapers START_PROFILE="/sapmnt/QAS/profile/QAS_ERS01_anftstsapers" \
   AUTOMATIC_RECOVER=false IS_ERS=true \
   op monitor interval=20 on-fail=restart timeout=105 op start interval=0 timeout=600 op stop interval=0 timeout=600 \
   --group g-QAS_AERS
   
   sudo pcs resource meta rsc_sap_QAS_ERS01  resource-stickiness=3000
   
   sudo pcs constraint colocation add g-QAS_AERS with g-QAS_ASCS -5000
   sudo pcs constraint order start g-QAS_ASCS then start g-QAS_AERS kind=Optional symmetrical=false
   sudo pcs constraint order start g-QAS_ASCS then stop g-QAS_AERS kind=Optional symmetrical=false
   
   sudo pcs node unstandby anftstsapcl1
   sudo pcs property set maintenance-mode=false
   

   If you're upgrading from an older version and switching to enqueue server 2, see SAP Note 2641322.

   Note

   The higher timeouts that are suggested when you use NFSv4.1 are necessary owing to protocol-specific pause, which is related to NFSv4.1 lease renewals. For more information, see NFS in NetApp best practice. The timeouts in the preceding configuration are only examples and might need to be adapted to the specific SAP setup.

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

   sudo pcs status
   
   # Online: [ anftstsapcl1 anftstsapcl2 ]
   #
   # Full list of resources:
   #
   # rsc_st_azure    (stonith:fence_azure_arm):      Started anftstsapcl2
   #  Resource Group: g-QAS_ASCS
   #      fs_QAS_ASCS        (ocf::heartbeat:Filesystem):    Started anftstsapcl2
   #      nc_QAS_ASCS        (ocf::heartbeat:azure-lb):      Started anftstsapcl2
   #      vip_QAS_ASCS       (ocf::heartbeat:IPaddr2):       Started anftstsapcl2
   #      rsc_sap_QAS_ASCS00 (ocf::heartbeat:SAPInstance):   Started anftstsapcl2
   #  Resource Group: g-QAS_AERS
   #      fs_QAS_AERS        (ocf::heartbeat:Filesystem):    Started anftstsapcl1
   #      nc_QAS_AERS        (ocf::heartbeat:azure-lb):      Started anftstsapcl1
   #      vip_QAS_AERS       (ocf::heartbeat:IPaddr2):       Started anftstsapcl1
   #      rsc_sap_QAS_ERS01  (ocf::heartbeat:SAPInstance):   Started anftstsapcl1
   

10. [1] Run the following step to configure priority-fencing-delay (applicable only as of pacemaker-2.0.4-6.el8 or higher).

    Note

    If you have a two-node cluster, you have the option to configure the priority-fencing-delay cluster property. This property introduces more delay in fencing a node that has higher total resource priority when a split-brain scenario occurs. For more information, see Can Pacemaker fence the cluster node with the fewest running resources?.

    The property priority-fencing-delay is applicable for pacemaker-2.0.4-6.el8 version or higher. If you're setting up priority-fencing-delay on an existing cluster, make sure to clear the pcmk_delay_max setting in the fencing device.

    sudo pcs resource defaults update priority=1
    sudo pcs resource update rsc_sap_QAS_ASCS00 meta priority=10
    
    sudo pcs property set priority-fencing-delay=15s
    

11. [A] Add firewall rules for ASCS and ERS on both nodes.

    # Probe Port of ASCS
    sudo firewall-cmd --zone=public --add-port={62000,3200,3600,3900,8100,50013,50014,50016}/tcp --permanent
    sudo firewall-cmd --zone=public --add-port={62000,3200,3600,3900,8100,50013,50014,50016}/tcp
    # Probe Port of ERS
    sudo firewall-cmd --zone=public --add-port={62101,3201,3301,50113,50114,50116}/tcp --permanent
    sudo firewall-cmd --zone=public --add-port={62101,3201,3301,50113,50114,50116}/tcp
    

SAP NetWeaver application server preparation

Some databases require that the database instance installation runs on an application server. Prepare the application server VMs to be able to use them in these cases.

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

The following items are prefixed with either:

• [A]: Applicable to both PAS and AAS
• [P]: Only applicable to PAS
• [S]: Only applicable to AAS

1. [A] Set up hostname resolution.

   You can either use a DNS server or modify the /etc/hosts file 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 SAP NetWeaver ASCS
   192.168.14.9 anftstsapvh
   # IP address of the load balancer frontend configuration for SAP NetWeaver ASCS ERS
   192.168.14.10 anftstsapers
   192.168.14.7 anftstsapa01
   192.168.14.8 anftstsapa02
   

2. [A] Create the sapmnt directory.

   sudo mkdir -p /sapmnt/QAS
   sudo mkdir -p /usr/sap/trans
   
   sudo chattr +i /sapmnt/QAS
   sudo chattr +i /usr/sap/trans
   

3. [A] Install the NFS client and other requirements.

   sudo yum -y install nfs-utils uuidd
   

4. [A] Add mount entries.

   If you use NFSv3:

   sudo vi /etc/fstab
   
   # Add the following lines to fstab, save and exit
   192.168.24.5:/sapQAS/sapmntQAS /sapmnt/QAS nfs rw,hard,rsize=65536,wsize=65536,nfsvers=3
   192.168.24.4:/transSAP /usr/sap/trans nfs rw,hard,rsize=65536,wsize=65536,nfsvers=3
   

   If you use NFSv4.1:

   sudo vi /etc/fstab
   
   # Add the following lines to fstab, save and exit
   192.168.24.5:/sapQAS/sapmntQAS /sapmnt/QAS nfs rw,hard,rsize=65536,wsize=65536,nfsvers=4.1,sec=sys
   192.168.24.4:/transSAP /usr/sap/trans nfs rw,hard,rsize=65536,wsize=65536,nfsvers=4.1,sec=sys
   

   Mount the new shares.

   sudo mount -a
   

5. [P] Create and mount the PAS directory.

   If you use NFSv3:

   sudo mkdir -p /usr/sap/QAS/D02
   sudo chattr +i /usr/sap/QAS/D02
   
   sudo vi /etc/fstab
   # Add the following line to fstab
   92.168.24.5:/sapQAS/usrsapQASpas /usr/sap/QAS/D02 nfs rw,hard,rsize=65536,wsize=65536,nfsvers=3
   
   # Mount
   sudo mount -a
   

   If you use NFSv4.1:

   sudo mkdir -p /usr/sap/QAS/D02
   sudo chattr +i /usr/sap/QAS/D02
   
   sudo vi /etc/fstab
   # Add the following line to fstab
   92.168.24.5:/sapQAS/usrsapQASpas /usr/sap/QAS/D02 nfs rw,hard,rsize=65536,wsize=65536,nfsvers=4.1,sec=sys
   
   # Mount
   sudo mount -a
   

6. [S] Create and mount the AAS directory.

   If you use NFSv3:

   sudo mkdir -p /usr/sap/QAS/D03
   sudo chattr +i /usr/sap/QAS/D03
   
   sudo vi /etc/fstab
   # Add the following line to fstab
   92.168.24.5:/sapQAS/usrsapQASaas /usr/sap/QAS/D03 nfs rw,hard,rsize=65536,wsize=65536,nfsvers=3
   
   # Mount
   sudo mount -a
   

   If you use NFSv4.1:

   sudo mkdir -p /usr/sap/QAS/D03
   sudo chattr +i /usr/sap/QAS/D03
   
   sudo vi /etc/fstab
   # Add the following line to fstab
   92.168.24.5:/sapQAS/usrsapQASaas /usr/sap/QAS/D03 nfs rw,hard,rsize=65536,wsize=65536,nfsvers=4.1,sec=sys
   
   # Mount
   sudo mount -a
   

7. [A] Configure the 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 VM 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 the 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 VMs on Red Hat Enterprise Linux. For a list of supported databases, see SAP Note 1928533.

• Run the SAP database instance installation.

  Install the SAP NetWeaver database instance as the root by using a virtual hostname that maps to the IP address of the load balancer front-end configuration for the database.

  You can use the sapinst parameter SAPINST_REMOTE_ACCESS_USER to allow a nonroot user to connect to sapinst.

  sudo <swpm>/sapinst SAPINST_REMOTE_ACCESS_USER=sapadmin
  

SAP NetWeaver application server installation

Follow these steps to install an SAP application server.

1. Prepare the application server.

   Follow the steps in the previous section SAP NetWeaver application server preparation to prepare the application server.

2. Install the 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 nonroot user to connect to sapinst.

   sudo <swpm>/sapinst SAPINST_REMOTE_ACCESS_USER=sapadmin
   

3. Update the 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 as <sapsid>adm.

   hdbuserstore List
   

   All entries should be listed and look similar to:

   DATA FILE       : /home/qasadm/.hdb/anftstsapa01/SSFS_HDB.DAT
   KEY FILE        : /home/qasadm/.hdb/anftstsapa01/SSFS_HDB.KEY
   
   KEY DEFAULT
     ENV : 192.168.14.4:30313
     USER: SAPABAP1
     DATABASE: QAS
   

   The output shows that the IP address of the default entry is pointing to the VM and not to the load balancer's IP address. You need to change this entry to point to the virtual hostname of the load balancer. Make sure to use the same port (30313 in the preceding output) and database name (QAS in the preceding output).

   su - qasadm
   hdbuserstore SET DEFAULT qasdb:30313@QAS SAPABAP1 <password of ABAP schema>
   

Test the cluster setup

Thoroughly test your Pacemaker cluster. For more information, see Execute the typical failover tests.

Next steps

• To deploy a cost-optimization scenario where the PAS and AAS instances are deployed with the SAP NetWeaver HA cluster on RHEL, see Install SAP dialog instance with SAP ASCS/SCS high availability VMs on RHEL.
• See HA for SAP NW on Azure VMs on RHEL for SAP applications multi-SID guide.
• See Azure Virtual Machines planning and implementation for SAP.
• See Azure Virtual Machines deployment for SAP.
• See Azure Virtual Machines DBMS deployment for SAP.
• To learn how to establish HA and plan for disaster recovery of SAP HANA on Azure (large instances), see SAP HANA (large instances) high availability and disaster recovery on Azure.
• To learn how to establish HA and plan for disaster recovery of SAP HANA on Azure Virtual Machines, see High availability of SAP HANA on Azure Virtual Machines.