Your architecture planning can include the VMs you want to migrate, the networks used for virtual machine traffic, and the networks you want to extend. This topic summarizes some maximum and minimum values for the deployment components.

The Hybrid Cloud Manager appliance must be installed on the vCenter that requires hybrid services. There can be only one Hybrid Cloud Manager deployment per vCenter. This restriction applies to linked mode: the Hybrid Cloud Manager management appliance is only installed in the primary vCenter. The Hybrid Cloud Manager supports up to five registered vCenters (in linked mode).

The maximum number of cloud endpoints is ten. To find the number of endpoints, Hybrid Cloud Manager tracks vCenter connections to the cloud.

Maximum Number of Migration and Network Extension Processes lists the number of processes you can run concurrently, through the UI or with scripts.

Maximum Number of Migration and Network Extension Processes

On Premises



Max concurrent low downtime migration tasks


Total migration tasks (forward and reverse combined) per Hybrid Cloud Manager deployment.

Max concurrent standard Layer 2 stretching tasks


Simultaneous stretch operations. Applies to the extend network "Select source port groups" wizard page.

Max concurrent HT L2C stretching tasks


Max concurrent vMotion migration tasks


Hybrid Cloud Manager is an add-on to the vCloud Air service. Hybrid Cloud Manager Performance Estimates estimates the performance for each option and each Layer 2 Concentrator appliance.

High throughput L2 extension performance numbers are based on jumbo frames and Direct Connect private line connectivity. Results over Internet paths or private lines with 1500 byte MTU can degrade performance by 15% to 20%. However, the LAN side still supports jumbo frames.

Hybrid Cloud Manager Performance Estimates

Hybrid Cloud Manager


Standard L2C



TCP/SSL Internet or Direct Connect

Licensed for up to 100 Mbps



~600–700 Mbps at 10–15 ms latency




3–4 Gbps@ 100 fps per network

When you decide which networks to stretch, consider the workloads on the network, and determine whether a high throughput stretched network is required. Your architecture can include both standard and high throughput Layer 2 Concentrators.

The standard L2C stretches vLANs and VXLANs. You can use trunking to maximize a single appliance for low throughput cases (500 Mbps or below).

The HT L2C stretches a single VLAN. If you are using a Direct Connect line, an HT L2C appliance makes the best use of the bandwidth. An HT L2C is required if you need zero-downtime migration (vMotion).

Layer 2 Stretched Network Limits

On Premises



Max standard L2 stretched networks


200 is the number of stretched networks tested, not a true limit.

Max HT L2C


One stretched network per HT L2C appliance.


When you must connect more than ten stretched networks to vCloud Air, you need Advanced Networking Services Premium with the sub interface feature enabled.