At CERN, we run OpenStack and ceph across two data centres to address some of our needs for resilience.

Some background on the approach is at https://inspirehep.net/files/18ee7c0191e1d04bc99e068c44967b49 and https://indico.cern.ch/event/1338689/contributions/6010769/ (presentation and paper at the bottom).

We’ve set up two OpenStack independent regions and have investigated various approaches such as rbd mirroring and multi-site S3 to provide redundancy. We continue working with upstream in areas such as CephFS replication/snapshotting.

It may be worth getting in touch with the OpenStack VMWare migration working group (https://www.openstack.org/vmware-migration-to-openstack/) to see how others are investigating achieving similar goals.

Tim

On 23 Apr 2025, at 09:27, KK CHN <kkchn.in@gmail.com> wrote:

Folks ,

I am exploring the possibility of OpenStack  to    set up  an On Prem DC and  Near line DR using OpenStack .  I have exposure to OpenStack from the Ussuri version onwards but am not a master of  OpenStack. 

Objective is  to  achieve near zero data loss of the growing VMs  at the DC   replicated in real time to the Near Line DR.  At times of a DC crash or for scheduled maintenance activity to ensure business continuity (RPO near zero and RTO 30 minutes - 1 Hour) to operate from the DR site. 


Heard about  similar solutions exists for  VMWare  or any proprietary OEM  like vSphere replication,vSAN and SRM to orchestrate  failover and fallback with   RPO near zero and RTO 30 minutes to 1 Hr. But not an option due to budget constraints at the moment.

What ways do folks at OpenStack achieve  this kind of requirement?   The underlying tools and techniques I have chosen to deploy and the best possible design of DC  and DR to achieve the objectives.

Any  hints and guidance to start, much appreciated.

Thank you,
Krishane