Messaging Broker HA Live / Backup Pairs - Shared Store on EBS: setup fails

Scenario:

This scenario is inspired by High Availability - Shared Store and is an attempt to replicate that setup on AWS using AWS EBS as storage:

• we have 2 EC2 instances created from Red Hat AMI (RHEL-7-JBEAP-7.4.0_HVM_GA-20210909-x86_64-0-Access2-GP2); both EC2 instance type must support multi attach (e.g. t3.medium)
• the first instance is configured as Live node (LIVE.standalone-ec2-full-ha.xml)
• the second instance is configured as Backup node (BACKUP.standalone-ec2-full-ha.xml)
• both instances use shares storage on an external AWS EBS File system which is attached on both EC2 instances

This scenario presents two main flaws:

• setup fails
• limitation: EBS Multi-Attach only with EC2 instances in the same Availability Zone

setup fails

According to AWS (see https://aws.amazon.com/blogs/storage/clustered-storage-simplified-gfs2-on-amazon-ebs-multi-attach-enabled-volumes/) EBS works in multi attached configuration (= shared storage) only in conjunction with some cluster aware filesystem like GFS2;

Following the procedure depicted in https://aws.amazon.com/blogs/storage/clustered-storage-simplified-gfs2-on-amazon-ebs-multi-attach-enabled-volumes/ on one of our Red Hat AMI (RHEL-7-JBEAP-7.4.0_HVM_GA-20210909-x86_64-0-Access2-GP2) you get an error on the firts step in "Installing the cluster software":

$ yum install pcs pacemaker fence-agents-aws -y
...
Error: Package: fence-agents-aws-4.0.11-86.el7.x86_64 (rhel-7-server-rhui-rpms)
           Requires: python-boto3
 You could try using --skip-broken to work around the problem
 You could try running: rpm -Va --nofiles --nodigest

limitation: EBS Multi-Attach only with EC2 instances in the same Availability Zone

According to https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/ebs-volumes-multi.html: "Amazon EBS Multi-Attach enables you to attach a single Provisioned IOPS SSD (io1 or io2) volume to multiple instances that are in the same Availability Zone."

questions

Is it worth to fix the setup issue on our AMI and provide support for this scenario on AWS?