A customer recently reached out to me with the issue below, while I hadn’t seen this issue before I thought I would check to see what I could dig up before they opened a ticket with Veeam support. “Error: Failed to call RPC function ‘StartAgent’: Timed out requesting agent port for client sessions.”

Veeam KB 1922 to the rescue, the cause of this issue is the ‘configuration of a Windows server within the Veeam console being set to have a limited number of ports to use‘ which thankfully can be resolved quite easily. To resolve simply go to the ‘Backup Infrastructure’ section in your VBR (Veeam Backup and Replication) console, go to the properties of any Windows servers that are being used by the job that is failing. So in this customers case, we can start with the backup proxy, then the backup repository, then if the problem still persists we can increase the port range on the VBR server as well. Once the port range is increased we simply click OK to apply the changes, I recommended we start with a relatively small number of ports (50) and increase if the problem still persists.

I haven’t figured out why in this customers case they encountered this port exhaustion issue, I find it curious as I’ve worked on much larger Veeam deployments before that didn’t encounter this issue. Ill need to perform some investigation and report back here once I learn more.

**UPDATE** Restarting the VBR server has resolved the issue without having to increase the port range. If it continues to happen we’ll look at increasing the port range but until then the default settings are good to stay.