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vCloud Air® Hybrid Cloud Manager™ Installation and Administration Guide
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Table 1: Virtual Machine Installation Resource Requirements
VM vCPUs RAM Installation
Hybrid Cloud Manager 4 12 GB Required.
Hybrid Cloud Gateway 2 2 GB Required.
Layer 2 Concentrator (L2C) 6 8GB Optional for migration, required for stretched Layer 2, or migration over stretched Layer 2.
WAN Optimizer 8 14 GB Optional.
During the installation process you can choose the Cluster/Host that will host the VMs for the Hybrid Cloud Manager,
the Hybrid Cloud Gateway, and the Layer 2 Concentrator (L2C). The WAN Optimizer is automatically deployed to a host
that best meets its requirements (as determined by vSphere at the time of the installation).
Hybrid Cloud Manager
The Hybrid Cloud Manager virtual appliance is Installed on-premises only and contains all other virtual appliance on-
board, simplifying the download and the installation process.
Hybrid Cloud Gateway
The Cloud Gateway maintains a secure channel between vSphere and a vCloud Air. The channel secures access for
vSphere protocols that are not tenant-aware, and provides intelligent routing capabilities to avoid networking "middle
mile" security problems. Since the Cloud Gateway uses strong encryption, no corporate VPN changes are required for
Hybrid Cloud Manager functionality.
The Cloud Gateway also incorporates vSphere replication technology to perform bidirectional migration. For more about
vSphere Replication usage and virtual machine migration, please see “Understanding Replication-Based Migration,” on
page 30.
Layer 2 Concentrator
The Network Extension Service extends a network from a vSphere Distributed Switch (vDS) to a vCloud Air.
The Layer 2 Concentrator (L2C) service appliance functions as a translation bridge to extend VLANs to VXLAN in vCloud
Air or as a transparent bridge when VXLAN and NSX-vSphere Edition is used on-premises. It has two interfaces:
• Internal Trunk interface: handles virtual machine traffic on-premises for the extended networks.
• Uplink interface: encapsulated overlay traffic is sent via this interface to and from vCloud Air.
When the virtual appliance is configured, you can masquerade the L2C behind the Cloud Gateway and share its IP
address. This allows ease of install in that the Cloud Gateway, L2C, and WAN Optimization appliance only require one IP
address. This is possible when selecting the deployment option where Extended Network traffic is routed via Hybrid
Transport (via Cloud Gateway). It is also possible to use a unique IP address for the L2C, thereby separating the
migration path and the stretched network data path. The latter approach is used in conjunction with scale out
deployment for multiple L2Cs and when using Direct Connect private lines where strong encryption may not be required
for extended networks.
WAN Optimization
The WAN Optimization appliance is an optional, yet highly recommended, component that performs WAN conditioning
to reduce effects of latency, Forward Error Correction to negate packet loss scenarios, deduplication of redundant traffic