We are purchasing two new dedicated servers. I originally had planned to purchase the XenServer 6.0 Advanced add-on which gives you the following features:
Specifically these features
- Distributed virtual switching
- Heterogeneous Pools
- High Availability
The standard (free) version includes VM disk snapshot and revert and XenMotion Live Migration.
We plan to have one server in one of SoftLayer's Dallas data center's and one in their Washington D.C. data centers. They will be able to talk to each other over the private network that is setup once we allow the two vlan's to "bridge".
Thinking about it more now, just a few days before the order is placed. I wonder if we will actually get any use out of the Advanced features which seem to be geared towards having two XenServer's in the same V-LAN.
We will only have a few VM's on each server and they don't need to be immediately moved from one to the other. If something happens to one we will take it down and manually move the VM to the other machine.
Between the two servers having the Advanced feature will cost $100 additional per month.
Simple answer: No, they are not and you should know it.
This is not about "xen features" but about this thing called "real world".
Machine M fails from Location A to B. Suddenly all the heavy traffic goes from A over the slow pipe. Have fun. If M is your main database server, real world physics just introduces a serious bottleneck, unlesss you have a nice 1gibt or a LOT higher connection. And even then latency will turn visible.
Ever tried to sync all changes on the discs of a heavy duty database server over a WAN? Have fun.
Same here. Virtual switching only works flawless if your connectivity is "enough" and "equal". Introduce a damn slow WAN link into the game and you better start planning your network boundaries WELL.
I would go for the Advance edition! You also get a more feturerich performance monitoring. And then you get StorageMotion. See more her http://www.citrix.com/products/xenserver/features/editions.html