Businesses increasingly demand cost savings and efficiency in the use of IT resources, yet the rate of storage growth continues to increase year on year which is becoming a big challenge for IT departments. Production storage is typically one of the largest cost items in any data center and utilizing the storage for what it was bought for and being able to buy most cost efficient storage required is key for any IT department to meeting the needs of the business.
Yet because of the requirement for SAN replication for enterprise-class BC/DR; the exact same storage vendor make and model needs to be matched in both the source and target sites often requiring organizations to purchase 2 of every storage array for each new project, upgrade or refresh. This removes flexibility, choice and therefore increases cost. Worse still, the actual storage space used by configuring SAN replication requires significant reserve space which wastes space in both storage arrays by consuming often 30%+ in addition to the utilized storage for Virtual Machines (VMs).
Zerto Virtual Replication replicates within the hypervisor and making it storage-agnostic so users can replicate from any type of storage to any type of storage. This allows the ability to:
- Leverage existing, underutilized storage as the replication target
- Leverage lower-cost storage at the replication site
- Mix and match storage technologies based on cost, performance and SLAs rather than technical limitations
By replicating in the hypervisor flexibility is increased, costs reduced and disaster recovery simplified. Because Zerto protects specific VMs and not entire LUNs, it enables reductions of overall storage and network requirements by:
- Utilize less people or skillsets as all of the replication is managed in the hypervisor by the virtualization team
- Reducing the overall number of LUNs required by utilizing same LUNs for multiple applications
- Reduce complexity by not having to match LUN configurations between sites
- Reduce network costs and bandwidth requirements by replicating just the VMs selected
- Remove the need for configuring snapshot and replica reserves in the storage array
Analyzing SAN replication space wastage
With SAN replication the replication is configured on a LUN basis. This typically requires a snapshot and replication reserve to be pre-committed in both the source and target storage which can be anything from 30% +, sometimes 100%, of additional storage usage above the replicated VM data.
Protecting 30TB of VM data with SAN replication can result in at least 39TB of data usage in the recovery site and an additional 9TB in the production storage with replication reserves taken into account. This totals an additional 18TB of storage usage just for configured SAN replication.
As environments scale the storage wastage becomes an even larger problem as production storage is expensive, wasting it for configuring snapshot based SAN replication and the ability to recover to previous points in time is not using the storage efficiently as it is wasting more and more space on snapshot and replica reserves.
With Zerto Virtual Replication all of the replication is managed in the hypervisor, removing any reliance on the underlying storage, so there is no need for configuring any snapshots or replica reserves at the storage array level. By utilizing journal based protection for point in time recovery, which uses a thin virtual disk on a per-VM basis stored in the recovery site, this significantly reduces the storage usage of the replication as it typically uses 7-10% of additional space. This enables an immediate disk space saving of at least 20%+ over any storage based replication solution which is a significant cost saving that allows for future storage growth with existing storage capacity.
Protecting 30TB of VM data with Zerto Virtual Replication would consume 33TB in the recovery site and uses no production storage at all, saving up to 18TB total storage requirements in comparison to SAN replication. The benefits don’t end there;
- Zerto journaling allows point in time recovery to increments every few seconds up to 14 days in the past
- Journals automatically re-claim space after large amounts of data change enabling further storage savings
- Recovery to any point in time has no impact on the Recovery Time Objective (RTO) of minutes
- Journals can be placed on separate storage to the replica VM
- Maximum size and warning limits can be configured to limit the space allocated for journaling
Only Zerto Virtual Replication allows the flexibility and space savings of replicating from any storage to any storage without the overheads of configuring snapshot and replication reserves significantly reducing storage requirements while simultaneously reducing complexity.