Limitations on VMware ESX/ESXi
This section describes the deployment and feature options that the ESX SteelHead-c does not support.
Deployment limitations
• Automatic peering - ESX SteelHead-c virtual appliances deployed with Web Cache Communication Protocol (WCCP) or Policy-Based Routing (PBR) support automatic peering. ESX SteelHead-c virtual appliances deployed with the Discovery Agent do not support automatic peering.
• Simplified routing - ESX SteelHead-c virtual appliances deployed in-path with the Discovery Agent support simplified routing. ESX SteelHead-c virtual appliances deployed with WCCP or PBR do not support simplified routing.
Feature limitations
• RSP - RSP enables virtualization in physical SteelHead appliances. SteelHead-c is a virtual SteelHead CX appliance running on a virtual machine. There is no need for additional layers of virtualization.
• PFS - It is easier to run a separate file server instance in the cloud and not use the SteelHead-c for Proxy File Service (PFS).
• WAN visibility mode - ESX SteelHead-c virtual appliances deployed with WCCP or PBR support WAN visibility mode. When deployed with the Discovery Agent, however, WAN visibility mode is not supported.
• CIFS prepopulation - ESX SteelHead-c virtual appliances deployed with WCCP or PBR support CIFS prepopulation. When deployed with the Discovery Agent, however, CIFS prepopulation is not supported.
Reduced data store feature
Note: This feature is only supported on ESX-based SteelHead-c virtual appliances.
In SteelHead-c versions before 1.2, you must allocate a data store volume of exactly 440 GB for the virtual appliance; otherwise, the SteelHead-c does not function correctly.
The reduced data store support feature in SteelHead-c 1.2 first checks if 440 GB of disk space is allocated for the data store. If less than 440 GB of disk space has been provisioned, the SteelHead-c software creates a 30-GB data store. This allows you to create SteelHead-c that require less disk space but still provide WAN optimization. The optimization performance is impacted when you do not use a 440-GB disk for the data store. Performance depends on the size of your working data set.
The SteelHead-c uses either 440 GB or 30 GB. If you allocate a disk space that is less than 440 GB, but later than 30 GB (such as 250 GB), the SteelHead-c uses only 30 GB; it disregards 220 GB. If you allocate less than 30 GB, the SteelHead-c does not function correctly.
After you create a disk, if you resize it to 440 GB, the SteelHead-c still uses only 30 GB. To increase the data store size to 440 GB, you must delete the original disk and create a new 440 GB disk. Doing this reverts the data store to a “cold” state; performance improves as the SteelHead executes subsequent data transfers over the WAN.