I was recently tasked with creating an isolated DR environment for the purpose of testing. The isolated environment in this instance was a single ESXi host with a virtual switch with no attached uplinks.
The objective of the DR test was to fail over to replicated virtual machines (using vRanger Pro) which existed in DMZ and internal networks and to be able to route traffic between hosts on those networks.
In order to achieve this I downloaded the virtual appliance Vyatta VC 6.0 (Final) from the Virtual Appliance (VA) marketplace (https://solutionexchange.vmware.com/store/category_groups/19).
Once the VA had been downloaded and imported to vCenter, I then configured the appliance as per my environment, excellent videos may be found here to help you along;
http://www.youtube.com/watch?v=ru6xwEg5Tlw
Once installed and configured, I was able to communicate with hosts in the DMZ and Internal networks. However, I did seem to experience issues with network performance with virtual machines configured with the VMXNET3 virtual adapter. This is where I found the following article which explains an issue with Large Receive Offload (LRO) and the version of VMware Tools intergrated with the appliance.
There is a solution to this and a version of the VA available with integrates the latest version of VMware Tools with VA to resolve this issue. The updated VA and further information are available from;
http://roggyblog.blogspot.com/2010/07/vyatta-final-60-with-updated-vmtools.html
I can confirm that the above resolved all my issues with network performance when using VMNEXT3 apadter within a virtual machine.
More information on LRO can be found at:
http://en.wikipedia.org/wiki/Large_receive_offload
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