How Can I Move My HVR Hub Installation From EBS to AWS EFS Storage?

Question

How can I move my HVR Hub installation (HVR_HOME, HVR_CONFIG) from an Amazon Elastic Book Store (EBS) volume to Amazon Elastic File System (EFS)?

Environment

HVR Hub
Linux
AWS EC2
Amazon EFS
Amazon EBS

Answer

Test this process on a non-production environment before applying it to production.

To migrate your HVR Hub installation from EBS to EFS:

Prepare the EFS mount:
i. Create or identify an EFS file system in the same VPC as your HVR EC2 instance.
ii. Install the NFS client on all Hub nodes. For RHEL, CentOS, or Amazon Linux, run:
```
yum -y install nfs-utils
```
iii. Create the EFS target directory, for example /mnt/efs/hvr, and mount the EFS file system to verify permissions.
iv. Confirm that the HVR operating system user can read from and write to the mount. For example:
```
chown -R hvruser:hvruser /mnt/efs/hvr
```
Stop HVR processes:
i. Stop all relevant HVR services:
```
systemctl stop hvrhubserver
```
ii. Confirm that no HVR-related processes are still running:
```
ps -ef | grep hvr
```
Back up HVR_HOME and HVR_CONFIG using tar -czf or another preferred method.
Use rsync to copy the directories to the EFS mount while preserving file permissions and ownership:
```
rsync -a /home/hvruser/hvr_home/ /mnt/efs/hvr/hvr_home/
rsync -a /home/hvruser/hvr_config/ /mnt/efs/hvr/hvr_config/
```
You can use mv and a symlink instead, but most prefer to keep the original files for rollback.
Update environment variables:
i. Update HVR_HOME and HVR_CONFIG in all user profiles, such as .bash_profile, and update the system PATH.
ii. If HVR is managed by systemd, update /etc/systemd/system/hvrhubserver.service so ExecStart points to the new locations.
iii. Reload systemd:
```
systemctl daemon-reload
```

Mount EFS persistently:

i. Add the EFS mount to /etc/fstab on every node. For example:

fs-<id>.efs.<region>.amazonaws.com:/ /mnt/efs/hvr nfs4 nfsvers=4.1,rsize=1048576,wsize=1048576,hard,timeo=600,retrans=2,noresvport,_netdev 0 0

ii. Test the entry:

sudo umount /mnt/efs/hvr && sudo mount -a

For high availability (HA) deployments, configure the EFS mount and HVR Hub service consistently across all Hub nodes. If you use Pacemaker and Corosync, add the EFS mount as a cluster-managed filesystem resource so only the active node writes to the shared storage.

For multi-AZ deployments, configure the appropriate load balancer, virtual IP, or service endpoint. For more information, see HVR High Availability and the AWS EFS documentation.