Need much more details here as nothing given in your post can help.
What version of Veeam are you using? What operation are you doing - backup? Backup of VMs? Agent backups?
Did you check the logs for further information - C:\ProgramData\Veeam\Backup\Jobname
Hello, thank you for your answer, I am on Veeam version 12.3.0.310
I have the error in two cases, the first to make a backup on a VM where it was already in place but where there was a vps migration
The second is a new VM in public cloud
the error in the job log of the first:
A connection attempt failed because the connected party did not respond properly beyond a certain duration or an established connection failed because the connecting host did not respond ********** (System.Net.Sockets.SocketException)
[05.12.2024 20:39:05.087] <15> Warning (3) at System.Net.Sockets.Socket.InternalEndConnect(IAsyncResult asyncResult)
[05.12.2024 20:39:05.087] <15> Warning (3) at System.Net.Sockets.Socket.EndConnect(IAsyncResult asyncResult)
[05.12.2024 20:39:05.087] <15> Warning (3) at System.Net.Sockets.TcpClient.EndConnect(IAsyncResult asyncResult)
[05.12.2024 20:39:05.087] <15> Warning (3) at Veeam.Backup.Core.CForeignConnectionPool.OnConnected(IAsyncResult result)
I would suggest opening a support ticket to have them help with your issue. I cannot tell from the errors what might be happening. Also this is just community not technical support so we can help only as best we can with suggestions.