Operational Limits for SRM and vSphere Replication (2034768)

Details

Different limits apply to the numbers of virtual machines that you can protect using SRM, depending on whether you use array-based replication, vSphere Replication, or a combination of both. Limits also apply if you use vSphere Replication independently of SRM.

• The limits in this article apply to SRM 5.1 and 5.5 and to vSphere Replication 5.1 and 5.5. For the operational limits of SRM 5.0.x, see the Site Recovery Manager 5.0 Administration Guide.
• The limits in this article apply to SRM and vSphere Replication in a standard 1:1 configuration. For information about the limits of using SRM in a shared recovery site configuration, also known as an N:1 configuration, see Understanding Site Recovery Manager protection and recovery limits in a shared recovery-site (N:1) configuration (2008061).

Solution

• SRM Protection Limits for Array-Based Replication
• SRM Protection Limits for vSphere Replication Protection
• Combined Array-Based and vSphere Replication Protection Limits with SRM
• Deployment Limits for vSphere Replication with SRM
• Limits for Using vSphere Replication Independently of SRM

SRM Protection Limits for Array-Based Replication

If you establish bidirectional protection, in which site B serves as the recovery site for site A and at the same time site A serves as the recovery site for site B, these limits apply across both sites, and not per site. For example, if you are using array-based replication for bidirectional protection, you can protect a total of 1000 virtual machines across both sites. In a bidirectional implementation, you can protect a different number of virtual machines on each site, but the total number of protected virtual machines across both sites cannot exceed 1000. For example, you can protect 400 virtual machines from site B to site A and 600 virtual machines from site A to site B.

SRM Protection Limits for Array-Based Replication:

Item	Maximum
Protected virtual machines per protection group	500
Total number of protected virtual machines	1000 *
Protection groups per recovery plan	250 *
Recovery plans	250
Datastore groups	255 *
Concurrent recovery plans	10

* Refer to Limitations to Using SRM with Array-Based Replication in Large-Scale Environments (2059498).

SRM Protection Limits for vSphere Replication Protection

If you establish bidirectional protection, in which site B serves as the recovery site for site A and at the same time site A serves as the recovery site for site B, these limits apply across both sites, and not per site. For example, if you are using vSphere Replication for bidirectional protection, you can protect a total of 500 virtual machines across both sites. In a bidirectional implementation, you can protect a different number of virtual machines on each site, but the total number of protected virtual machines across both sites cannot exceed 500. For example, you can protect 200 virtual machines from site B to site A and 300 virtual machines from site A to site B.

SRM Protection Limits for vSphere Replication Protection:

Item	Maximum
Protected virtual machines per protection group	500
Total number of protected virtual machines	500
Protection groups per recovery plan	250
Recovery plans	250
Concurrent recovery plans	10

Combined Array-Based and vSphere Replication Protection Limits with SRM

With SRM, you can run array-based protection groups alongside vSphere Replication protection groups in the same SRM Server. However, the total number of protection groups cannot exceed 250. For example, you cannot create 150 array-based protection groups and then create 250 vSphere Replication protection groups, as this creates 400 protection groups in total. If you have 150 array-based protection groups, you can create an additional 100 vSphere Replication protection groups, to make a total of 250 protection groups.

Similarly, in a combined array-based and vSphere Replication setup, you can protect a maximum of 1000 virtual machines in total per SRM Server. If you establish bidirectional protection, in which site B serves as the recovery site for site A and at the same time site A serves as the recovery site for site B, this limit applies across both sites, and not per site.

You must remember that each replication type has a different maximum limit. The protection limit for array-based replication is 1000 virtual machines. The protection limit for vSphere Replication is 500 virtual machines. Because the maximum protection limit is 1000 virtual machines per SRM Server or per pair of SRM servers if you are using bidirectional protection, you cannot protect 1000 virtual machines with array-based replication and an also protect an additional 500 virtual machines with vSphere Replication. This results in a total of 1500 protected virtual machines, which exceeds the maximum limit.

As an example of a supported implementation, you could use array-based replication to protect 500 virtual machines and vSphere Replication to protect 500 virtual machines. Alternatively, you could use array-based replication to protect 900 virtual machines and vSphere Replication to protect 100 virtual machines. The combined total of virtual machines that you protect using array-based replication and vSphere Replication must not exceed 1000.

Combined Array-Based and vSphere Replication Protection Limits with SRM:

Item	Maximum
Protected virtual machines per protection group	500
Number of virtual machines protected by array-based replication	1000
Number of virtual machines protected by vSphere Replication	500
Total number of protected virtual machines (array-based replication + vSphere Replication)	1000
Protection groups per recovery plan	250
Recovery plans	250
Concurrent recovery plans	10

Deployment Limits for vSphere Replication with SRM

SRM 5.0.x included vSphere Replication 1.0.x. In vSphere Replication 1.0.x, you deployed a vSphere Replication management server and one or more vSphere Replication servers separately. The vSphere Replication management server manages the vSphere Replication infrastructure and the vSphere Replication servers handle the replication of virtual machines. In SRM 5.1 and later, you deploy vSphere Replication as a single combined appliance that contains a vSphere Replication management server and a vSphere Replication server that is automatically registered with the vSphere Replication management server. With SRM 5.1 and later, you can deploy and register additional vSphere Replication servers to balance the replication load across your virtual infrastructure. You can deploy up to 9 additional vSphere Replication servers per vSphere Replication appliance, to make a total of 10 vSphere Replication servers per vSphere Replication appliance. For more information, see Deploy an Additional vSphere Replication Server in Site Recovery Manager Installation and Configuration.

If you use vSphere Replication independently of SRM, you cannot deploy additional vSphere Replication servers. If you use vSphere Replication independently of SRM, the vSphere Replication appliance, with its single vSphere Replication server, supports a maximum of 500 replication schedules. When using vSphere Replication with SRM, the maximum number of replication schedules per vSphere Replication appliance is also 500. However, when using vSphere Replication with SRM, you should not exceed 100 replication schedules per vSphere Replication server. This limit applies to the vSphere Replication server that is embedded in the vSphere Replication appliance as well as to any additional vSphere Replication servers that you deploy. So, if you want to use vSphere Replication with SRM to replicate more than 100 virtual machines, you must deploy additional vSphere Replication servers. How you distribute the replication schedules across the vSphere Replication servers is unimportant, as long as no single vSphere Replication server has more than 100 replication schedules and the total number of replication schedules for the vSphere Replication appliance does not exceed 500.

For example, with SRM you can deploy 4 additional vSphere Replication servers, to make a total of 5 vSphere Replication servers registered with a vSphere Replication appliance. Each vSphere Replication server can handle 100 replication schedules, to make a total of 500 replication schedules. As another example, you can deploy 9 additional vSphere Replication servers, to make a total of 10 vSphere Replication servers (the maximum). One vSphere Replication server can handle 100 replication schedules (the maximum), 8 vSphere Replication servers can each handle 45 replication schedules, and one vSphere Replication server can handle 40 replication schedules.

Deployment Limits for vSphere Replication with SRM:

Item	Maximum
vSphere Replication servers registered to a vSphere Replication appliance, including the embedded vSphere Replication server	10
Virtual machine replication schedules per vSphere Replication server	100
Maximum number of virtual machines protected by vSphere Replication	500

Limits for Using vSphere Replication Independently of SRM

If you use vSphere Replication independently of SRM, you cannot deploy additional vSphere Replication servers. The maximum number of virtual machines that you can protect using vSphere Replication without SRM is 500 per appliance. If you establish bidirectional protection, in which site A serves as the recovery site for site B and at the same time site B serves as the recovery site for site A, these limits apply across both sites. If you are using vSphere Replication for bidirectional protection, you can protect a total of 500 virtual machines across both sites.

However, it is possible to create a vSphere Replication setup with more than two sites, in which each site has a vCenter Server instance and a vSphere Replication appliance. If you have more than two sites, you can protect more than 500 virtual machines. For example, you can create a setup with three sites, Site A, Site B, and Site C:

• Site A replicates 250 virtual machines to Site B
• Site A replicates 250 virtual machines to Site C
• Site B replicates 250 virtual machines to Site C

In this example, the total number of replicated virtual machines is 750, but each site only handles 500 replications:

• Site A has no incoming replications and 500 outgoing replications
• Site B has 250 incoming replications and 250 outgoing replications
• Site C has 500 incoming replications and no outgoing replications

By setting up more than two vSphere Replication sites, in which no individual site exceeds 500 replications, the total number of replications can be greater than 500.

Limits for Using vSphere Replication Independently of SRM:

Item	Maximum
vSphere Replication appliances per vCenter Server instance	1
Maximum number of protected virtual machines per vSphere Replication appliance	500