Deploy vSphere Replication for virtual machine replication in Site Recovery Manager. Consider the requirements for the operation of the management components that are failed over.

Replication Technology

You have the following options for replication technology when using Site Recovery Manager:

  • Array-based Replication using Storage Replication Adapters (SRAs) with Site Recovery Manager
  • vSphere Replication with Site Recovery Manager.
Table 1. Design Decisions on Replication Technology

Decision ID

Design Decision

Design Justification

Design Implication

SDDC-OPS-DR-010

Use vSphere Replication in Site Recovery Manager as the protection method for virtual machine replication.

  • Allows for flexibility in storage usage and vendor selection between the two disaster recovery regions.

  • Minimizes administrative overhead required to maintain Storage Replication Adapter compatibility between two regions of disaster recovery.

  • All management components must be in the same cluster.

  • The total number of virtual machines configured for protection using vSphere Replication is reduced compared with the use of storage-based replication.

Networking Configuration of the vSphere Replication Appliances

vSphere Replication uses a VMkernel management interface on the ESXi host to send replication traffic to the vSphere Replication appliance in the recovery region. Within the VMware Validated Design, the vSphere Replication traffic has been isolated to its own dedicated port group and VLAN per region ensuring there is no impact other vSphere management traffic. For more information about the vSphere Replication traffic on the management ESXi hosts, see Virtualization Network Design.

vSphere Replication appliances and vSphere Replication servers are the target for the replication traffic that originates from the vSphere Replication VMkernel ports.

Table 2. Design Decisions on the Networking Design of vSphere Replication

Decision ID

Design Decision

Design Justification

Design Implication

SDDC-OPS-DR-011

Dedicate a distributed port group to vSphere Replication traffic.

Ensures that vSphere Replication traffic does not impact other vSphere management traffic. The vSphere Replication servers potentially receive large amounts of data from the VMkernel adapters on the ESXi hosts.

You must allocate a dedicated VLAN for vSphere Replication.

SDDC-OPS-DR-012

When using two availability zones, dedicate a distributed port group to vSphere Replication traffic per availability zone.

  • VLANs ensure traffic isolation

  • vSphere Replication traffic between availability zones is routed which means an additional stretched VLAN is not required.

  • Limits extraneous networking use across the inter-site link (ISL).

  • Static routes on the ESXi hosts are required.

  • Enough VLANs are available within each cluster that should be used for traffic separation.

  • Host Profiles must be managed on a per-host level.

SDDC-OPS-DR-013

Dedicate a VMkernel adapter on the management ESXi hosts.

Ensures that the ESXi server replication traffic is redirected to the dedicated vSphere Replication VLAN.

None.

SDDC-OPS-DR-014

Attach a virtual machine NIC of the vSphere Replication VMs to the vSphere Replication port group.

Ensures that the vSphere Replication VMs can communicate on the correct replication VLAN.

vSphere Replication VMs might require additional network adapters for communication on the management and replication VLANs.

SDDC-OPS-DR-015

When using two availability zones, deploy an additional virtual machine NIC on the vSphere Replication VM to the vSphere Replication port group for the second availability zone.

  • Ensures that in the event of a disaster in a single availability zone, replication traffic to and from Region B is not interrupted.

  • Because of the unique VLANs and port groups for vSphere Replication traffic per availability zone, a virtual adapter must be connected to each port group to receive data.

During a disaster recovery scenario, you must maintain the IP address of the incoming storage traffic according to the accessibility of the availability zones in Region A.

By default, this is Availability Zone 1.

Snapshot Space During Failover Tests

To perform failover tests, you must provide additional storage for the snapshots of the replicated VMs. This storage is minimal in the beginning, but expands as test VMs write to their disks. Replication from the protected region to the recovery region continues during this time. The snapshots that are created while testing are deleted after the failover test is complete.

Sizing Resources for vSphere Replication

Select a size for the vSphere Replication nodes to facilitate virtual machine replication of the SDDC management components according to the objectives of this design.

Table 3. Compute Resources for a vShere Replication Node with 4 vCPUs

Attribute

Specification

Number of vCPUs

4

Memory

4 GB

Disk Capacity

18

Environment

Up to 2000 replications between nodes

Sizing is done according to the IT organization requirements. However, this design uses calculations for a single region. The design then mirrors the calculations for the other region. You must protect a total of 15 virtual machines. For information about the node configuration of the management components per region that is used in the calculations, see SDDC Nodes with Failover Support.

Table 4. Design Decisions on vSphere Replication Deployment and Size

Decision ID

Design Decision

Design Justification

Design Implication

SDDC-OPS-DR-016

Deploy each vSphere Replication appliance in the management cluster.

All management components must be in the same cluster.

None

SDDC-OPS-DR-017

Deploy each vSphere Replication appliance using the 4 vCPU size.

Accommodates the replication of the expected number of virtual machines that are a part of the following components:

  • vRealize Automation

  • vRealize Operations Manager

  • vRealize Suite Lifecycle Manager

None.