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I've got an SQL database on an azure VM (non domain) that i'd like to backup to our internal DPM 2012 server. I've installed the DPM agent on the Azure VM, setup DCOM to use only the ports 5000 to 5025 on both the VM and the DPM server, created the 135, 5000-5025, 5718 5719 endpoints on azure and on the VM's firewall.

When trying to add this agent to the DPM server, I end up with an error, "Unable to contact the protection Agent on server .cloudapp.net"

I know there is some sort of connection between them, as using a wrong password gives me an Invalid Credentials error.

The error seems to be DCOM related : When trying to connect to the Azure VM from the DPM server using VBEMTest, i get an Error "0x800706ba The RPC server is unavailable", but access is deneid when using wrong credentials )

What am i missing ? Has someone been able to achieve this kind of setup ?

Thanks for your help !

Florent Courtay
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1 Answers1

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RPC also uses ephemeral port ranges. On Server 2008 and later, that range is 49152 to 65535. In Server 2003 and earlier, it is 1025-5000.

If you wish to limit the RPC port range, so that it's easier to control what goes in and out of your firewall, you should check out this article, which coincidently covers DPM.

The reason you're seeing sporadic errors that hint at connectivity is that you can connect to the RPC endpoint mapper (135) which will return an available ephemeral port for RPC communication, but your firewall doesn't allow further communication on that assigned port.

MDMarra
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  • Tha's what i did, using the 5000-5025 port range – Florent Courtay Aug 23 '13 at 14:25
  • That isn't the port range for RPC on modern versions of Windows. You should consider specifying a port range that is valid to avoid conflicts with other services that might be using 5000-5025. Also, are you sure 25 dynamic ports is enough? – MDMarra Aug 23 '13 at 14:26
  • I'll try to change it for 50000->50100, adding endpoints in azure is horribly slow sadly... – Florent Courtay Aug 23 '13 at 14:31