Based upon the information provided it appears the issue is not with the vm itself so it maybe an issue with the host in regards to the overall host performance. It could be a load issue on the host which i'm sure has been checked but if there is another 4.1 host it maybe worthwhile moving the vm to that host to test it. Identifying any performance differences between when the vm is running on a 4.0.1 host and a 4.1 host might help shed some light on what is the difference between the two host is. It could possibly network related to that host and maybe introducing unnecessary latency. I hope this maybe of some help, probably not but thought I'd try.
What version of virtual hardware and tools are these VMs using? Does upgrading the tools when they are on the 4.1 host help? Keep in mind though, you should then downgrade them again if you are moving back to the U1 host.
Problem is I believe it is something to do with the host level mainly the build of ESX itself. This issue happens even if nothing else is on the host but the Citrix server. Tried both dual quad / 26GB ram and dual dual / 30GB ram hosts and a 2vCPU / 2GB VM is having issues running alone on the host.
Also the VM hardware is v7 but we don't upgrade the tools on the VM's until all of the hosts are at the highest level to avoid issues when you upgrade then have to revert host to earlier versions.
When the vm experiences the performance issues does the host as well ? I assume that the host backend is the same as the other esx hosts, storage, network, etc. Have other VMs on those host had similar performance issues? Are the performance metrics relatively the same for the Citrix VMs when they are on the 4.1 host as compared to the 4.0.1 host?
Nope to my knowledge all other VM's running on 4.1 hosts run just fine, its just the Citrix VM's
I am having 4 hosts x3950 IBM servers with SAN LUNS shared for each one. Hosts having ESX 3.5 U5.
We have been told to migrate to esxi 4.1. Also, this going to be fresh installation of ESXi 4.1 and will be migrating VMs runnning on ESX 3.5 back to it.
1 Install Windows OS on the physical server agreed to use for vcenter
2 Install Vcenter server 4.1 on new physical host with update manager
3 Create a new Datacentre on newly installed Vcenter server
4 Assign a new tempoarary IP to server
1 Login to old vcenter 2.5 and check the ESX & vm running properly
2 Vmotion all VM from ESX03 to ESX04 ( Shut down some of VM if not required )
3 Check all vm with respect to its functionality
4 Take details of all datastore and network interfaces attached to the ESX03 server
5 Take the backup of ESX server config
6 Remove the ESX03 from the datacenter
7 Perform a fresh installation of esx4.1 on the free host (i.e ESX03 )
8 Add in the Datacenter of VC 4.1
9 Configure the Datastore and Network Interfaces on newly installed ESX server ( Keep the existing old IP of the esx system )
10 Remove the ESX04 form the datacenter of VC 2.5
11 Add the ESX04 in the Datacenter of VC 4.1
12 Vmotion all vm from the ESX04 to ESX03 ( Newly installed ESX 4.1 )
13 Check all VM with respect to its functionality
so, I would like to know from you guys that is it OK? Also, do I have to do any HBA disconnections before proceeding the ESXi 4.1 installation? if yes, how to do that?
also, how abt the communication and vmotion on the new ESXi server, if I am ahving all the configuration working with 3.5 and on the same we going to migrate it. then will it work as the same if we providing the same ip for ESXi 4.1. IF NOT, what all things I have to do for doing VMotion after pulling back all the servers in the Vcenter4? Please help me with this. this activity I am supposed to do ASAP.
any help will be highly appreciated.
Thanks in advance.
I'm sure a new post should have been started but here are my thoughts. Looking through it everything looks good to me, in regards to the HBA disconnection i'm not %100 certain on that but would assume that once the host is powered off the connection will eventually drop on the storage side. If both hosts are in the same VC datacenter then vmotion should work just fine even if the ip address changed as long as the networking configuration has stayed the same.
The absolute first step is to verify that ALL your hardware is on the Hardware Compatibility List http://vmware.com/go/hcl including add in NICs, controllers, storage, HBAs etc.
You should also consider installing ESXi rather than ESX since 4.1 is the last version of ESX.