I have had a Phone conversation with the support engineer today.
we looked at quiet a few things
1) config of veeam
2) Proxy config ( no hotadd option at the moment)
3) connection between host and veeam sever
4) jumbo frames off on network adapter.
5) added 1 host as a stand alone host within Veeam ( still didnt work)
6) migrated the guest vm to a different data store.
7) from server a we were able to download the VMWare log, from the UTM we were unable to download the log file, even though both servers reside on the same datastore.
The engineer was very helpful and knowledgable however this issue looks like a new issue.
"normally we dont see an error message that long "10041633552057.NBD_ERR_NETWORK_CONNECT" so perhaps its a new issue idk.
However we are not giving up on this one ive mailed my results to the engineer and will see whats next.
I begining to think ( but am not sure) that there may be an issue on the underlying storage, is it possible that the folder on the Lun for server A has different rights to the folder for server B. ( just clutching at straws now :lol)
Ill have a look at the underlying storage to see if i can find anything,