Using SUSE Automation to Deploy an SAP HANA Cluster on AWS #

This document will walk you through the deployment of a simple two-node SAP HANA HA Cluster using the SUSE Automation Project for SAP Solutions Project and operating on AWS.

This project uses Terraform and Salt to deploy and configure the operating system (SUSE Linux Enterprise Server for SAP Applications), SAP software (SAP HANA), and a SUSE Linux Enterprise High Availability (HA) cluster. If extensive configuration and customization are required, refer to the project documentation at https://github.com/SUSE/ha-sap-terraform-deployments.

For simplicity, this guide uses the Cloud Shell to perform the deployment, as it provides easy access to most of the required tooling.

It is possible to use a local Linux or macOS computer, but some commands may need modification or omission.

The architecture for the deployment is similar to the one shown below:

Figure 1: AWS Automation Architecture #

 

The project will perform the following actions:

Start an AWS Cloud Shell from the AWS Services menu.

When the shell has launched, the next step is to configure the CLI and provide API access keys to allow the creation of AWS resources and infrastructure. The API Keys are created from the AWS console. For more details, refer to https://docs.aws.amazon.com/cli/latest/userguide/cli-configure-quickstart.html

The quickest way to configure the AWS CLI is by running the command:

aws configure

This is described in the documentation linked above.

The command generates a file in $HOME/.aws/credentials which is referenced later.

Important

The user specified in this step needs certain AWS permissions to ensure the deployment is successful.

Terraform is not currently deployed as part of the AWS Cloud Shell, in this step Terraform is downloaded and installed to the ~/bin directory. Update the command below with the latest version of Terraform as needed. As Terraform is updated on a regular basis, it may be necessary to update after installation, or specify a different version to download.

From the ~ directory, run:

mkdir ~/bin
cd ~/bin
wget https://releases.hashicorp.com/terraform/0.14.7/terraform_0.14.7_linux_amd64.zip
unzip terraform_0.14.7_linux_amd64.zip
cd ~

Check Terraform is working by running:

terraform --version

With the correct entitlement, SAP HANA media can be downloaded from the SAP Web site at https://support.sap.com/en/my-support/software-downloads.html. The SAP Media needs to be made available so it can be accessed during the deployment.

The SUSE Automation for SAP Applications project allows for three methods for presenting the SAP media:

The different formats come with some benefits and drawbacks:

In the example at hand, we use the compressed archives for the install (exe/RAR) as it is the easiest way to download and upload to the cloud share.

This guide uses the most recent SAP HANA media, SAP HANA 2.0 SPS05. The SAP HANA media file name downloaded at the time of creating this guide is 51054623. Follow the SAP instructions to download the SAP HANA media.

Tip

It is a good practice to have the SAP Media versioned on the cloud share to build a library for automatic installs and (re)deployments. Thus you should think about your SAP media structure first.

As an example, see below how a full SAP Application media tree (in a compressed format) for a S/4HANA version 1809 install would look like:

<FS>/s4hana1809
       ├SWPM_CD
       │  ├SWPM20SP07_5-80003424.SAR
       │  └SAPCAR_721-20010450.EXE
       │
       ├EXP_CD
       │  ├S4CORE104_INST_EXPORT_1.zip
       │  ├S4CORE104_INST_EXPORT_2.zip
       │  └...
       ├DBCLIENT_CD
       │  └IMDB_CLIENT20_005_111-80002082.SAR
       ├BASKET_CD
       │   ├SAPHOSTAGENT24_24-20009394.SAR
       │   ├igshelper_4-10010245.sar
       │   ├igsexe_1-80001746.sar
       │   ├SAPEXEDB_400-80000698.SAR
       │   └SAPEXE_400-80000699.SAR
       └HANA
          ├51053061_part1.exe
          ├51053061_part2.rar
          ├51053061_part3.rar
          └51053061_part4.rar


 HANA       : contains the HANA Database install
 BASKET_ CD : contains SAP kernel, patch + more like hostagent.
 DBCLIENT_CD: contains the package corresponding to DB CLIENT, e.g HANA
 EXP_CD     : contains the package corresponding to EXPORT files
 SWPM_CD    : must contain the .exe file corresponding to SAPCAR and the
              .sar file corresponding to SWPM.
              The file suffix must be .exe and .sar.

In the next steps, we use a simple HANA install download.

For AWS, an S3 bucket is used.

Using the AWS Console, perform the following actions:

The SUSE SAP Automation code is published in GitHub.

The following command will clone the project to the Cloud Shell ready for configuration:

$ git clone --depth 1 --branch 7.2.0 https://github.com/SUSE/ha-sap-terraform-deployments.git

Note

If the following SSH keys already exist, the next step can be skipped.

Then, generate SSH key pairs to allow for accessing the SAP HANA instances:

#optional if ssh-keys already exist
$ cd ~
$ ssh-keygen -q -t rsa -N '' -f  ~/.ssh/id_rsa

5.1 Configuring the deployment options and modifying the Terraform variables #

 

The files that need to be configured are contained in a subdirectory of the project. Use that as the working directory:

cd ~/ha-sap-terraform-deployments/aws

A Terraform example template is provided. For a demo environment consisting of a simple HANA cluster, only a handful of parameters will need changing.

Copy the Terraform example file to terraform.tfvars:

$ cp terraform.tfvars.example terraform.tfvars

Edit the terraform.tfvars file and modify it as explained below. If you are duplicating the lines before modification, ensure the original is commented out, or the deployment will fail.

With this parameter, Terraform will use the AWS credentials file created above. It is the simplest way to provide credentials for the deployment.

aws_credentials = "~/.aws/credentials"

If not used, ensure the following lines are commented out or the deployment will fail.

#aws_access_key_id = my-access-key-id
#aws_secret_access_key = my-secret-access-key

Choose the region for the deployment, for example:

# Region where to deploy the configuration
aws_region = "eu-central-1"

The following parameters select the version of SUSE Linux Enterprise Server for SAP Applications to deploy:

Note

The values shown equal the default values. All defaults point to PAYG images for an easy start. Thus you only need to enable or change the variables if you want to work with different values.

 // this is also the default
For simplicity, the 'os_owner' is set to use PAYG instances from the AWS Marketplace. If an existing SUSE subscription needs to be used, this section can be changed to use BYOS images. Refer to the project documentation.

#os_image = "suse-sles-sap-15-sp2"
#os_owner = "679593333241"

Next, enter the path for the public and private SSH keys that were generated earlier. Below is an example using the default created SSH keys:

# SSH Public key location to configure access to the remote instances
public_key  = "~/.ssh/id_rsa.pub"

# Private SSH Key location
private_key = "~/.ssh/id_rsa"

To keep the cluster architecture and deployment simple and to provide additional packages needed to deploy, uncomment and set the following parameters:

ha_sap_deployment_repo = "https://download.opensuse.org/repositories/network:/ha-clustering:/sap-deployments:/v7/"

Then, enable the pre_deployment parameter:

pre_deployment = true

Next, set which SAP HANA instance machine type should be selected: The default is set to some standard types, and you only need to enable and change the variable if you want other sizes.

#hana_instancetype = "r3.xlarge"

Next set the hostname for the instances, without the domain part

name = "hana"

Modify the following parameter to point to SAP media that was uploaded to the storage location:

hana_inst_master = "s3://mysapmedia/s4hana1809/HANA"

hana_archive_file = "{hana_archive_version}.exe"

To create the cluster, we need to set this parameter to true, otherwise only a single system is created.

# Enable system replication and HA cluster
hana_ha_enabled = true

Finally, to ensure a fully automated deployment, it is possible to set passwords within the terraform.tfvars file. Uncomment and set the following parameters to your own value:

hana_master_password = "SAP_Pass123"

Note

If the parameters are not set in the terraform.tfvars file, they must be entered when running the deployment.

Important

All passwords must conform to SAP password policies or the deployment will fail.

Optional: If a monitoring instance should be as part of the deployment, find and uncomment the following:

monitoring_enabled = true

If the deployment is being run from the root user of the AWS account, or if the user specified when configuring the AWS CLI has Admin privileges in your AWS account, you can skip this step.

If using an IAM user with limited permissions, additional IAM rights may be required as IAM policies are created and attached during deployment, for example to access and manage EC2 instances, S3 buckets, IAM (to create roles and policies) and EFS storage.

There are two options available to achieve this:

Tip

Depending on your own IAM rights, you may need to reach out to an AWS administrator for your account to set this up for you.

Create the following policy and attach it to the IAM user running the deployment:

{
    "Version": "2012-10-17",
    "Statement": [
        {
            "Effect": "Allow",
            "Action": [
                "iam:CreateServiceLinkedRole",
                "iam:PassRole",
                "iam:CreateRole",
                "iam:TagRole",
                "iam:GetRole",
                "iam:DeleteRole",
                "iam:GetRolePolicy",
                "iam:PutRolePolicy",
                "iam:DeleteRolePolicy",
                "iam:ListInstanceProfilesForRole",
                "iam:CreateInstanceProfile",
                "iam:GetInstanceProfile",
                "iam:RemoveRoleFromInstanceProfile",
                "iam:DeleteInstanceProfile",
                "iam:AddRoleToInstanceProfile"
            ],
            "Resource": "*"
        }
    ]
}

Terraform will create and name resources when running the deployment based on the "workspace" in use. It is highly recommended to create a unique workspace from which to run the deployment.

$ terraform init
$ terraform workspace new demo
$ terraform workspace select demo
$ terraform plan
$ terraform apply

Tip

The Cloud Shell has a timeout of around 20 minutes and the shell will close if left unattended, resulting in a failed deployment. It is strongly advised to retain focus on the Cloud Shell window to ensure the timeout does not occur.

If successful, the output will be the public IP addresses for the cluster nodes similar to the output below.

module.hana_node.module.hana_provision.null_resource.provision[1] (remote-exec):               ----------
module.hana_node.module.hana_provision.null_resource.provision[1] (remote-exec):               method:
module.hana_node.module.hana_provision.null_resource.provision[1] (remote-exec):                   update
module.hana_node.module.hana_provision.null_resource.provision[1] (remote-exec):               url:
module.hana_node.module.hana_provision.null_resource.provision[1] (remote-exec):                   /tmp/cluster.config
module.hana_node.module.hana_provision.null_resource.provision[1] (remote-exec):
module.hana_node.module.hana_provision.null_resource.provision[1] (remote-exec): Summary for local
module.hana_node.module.hana_provision.null_resource.provision[1] (remote-exec): -------------
module.hana_node.module.hana_provision.null_resource.provision[1] (remote-exec): Succeeded: 34 (changed=26)
module.hana_node.module.hana_provision.null_resource.provision[1] (remote-exec): Failed:     0
module.hana_node.module.hana_provision.null_resource.provision[1] (remote-exec): -------------
module.hana_node.module.hana_provision.null_resource.provision[1] (remote-exec): Total states run:     34
module.hana_node.module.hana_provision.null_resource.provision[1] (remote-exec): Total run time: 1384.111 s
module.hana_node.module.hana_provision.null_resource.provision[1] (remote-exec): Thu Aug 26 11:18:58 UTC 2021::hana02::[INFO] deployment done
module.hana_node.module.hana_provision.null_resource.provision[1]: Creation complete after 43m28s [id=xxxxxxxxxxxxxx]

Apply complete! Resources: 33 added, 0 changed, 0 destroyed.

Outputs:

cluster_nodes_ip = [
  "10.0.1.10",
  "10.0.2.11",
]
cluster_nodes_name = [
  "i-0a553e68e157ed667",
  "i-00887a206e454b0ab",
]
cluster_nodes_public_ip = [
  "18.192.212.32",
  "3.66.190.173",
]
cluster_nodes_public_name = [
  "ec2-18-192-212-32.eu-central-1.compute.amazonaws.com",
  "ec2-3-66-190-173.eu-central-1.compute.amazonaws.com",
]
drbd_ip = []
drbd_name = []
drbd_public_ip = []
drbd_public_name = []
iscsisrv_ip = ""
iscsisrv_name = ""
iscsisrv_public_ip = ""
iscsisrv_public_name = ""
monitoring_ip = ""
monitoring_name = ""
monitoring_public_ip = ""
monitoring_public_name = ""
netweaver_ip = []
netweaver_name = []
netweaver_public_ip = []
netweaver_public_name = []

When finished with the deployment, or even if the deployment has failed, ensure that Terraform is used to tear down the environment.

$ terraform destroy

This method will ensure all AWS resource, such as instances, volumes, VPCs, and IAM roles, are cleaned up.

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