RPC Error adding Hyper-V Server

[MIDAC]

We are trying to test Veeam Backup & Replication 6.0 in our lab but having issues adding our Hyper-V server.

At the Credentials step we enter the username & password and click next. It says "Enumerating installed components" for a while, then get the following error...

Unable to connect via WMI. Hostname: XXX.ABC.local
Server 'XXX.ABC.local' does not exist or access denied. Check firewall settings.
The RPC server is unavailable. (Exception from HRESULT: 0x800706BA)

Our Hyper-V server is a standalone Windows 2008 R2 server with the Hyper-V role (so not a core install). The firewall is turned on, turning it off is not really an option, however we can add exceptions. Veeam is installed on a Windows 7 PC which also has the firewall turned on.

Any ideas and suggested firewall settings would be appreciated.. thanks!

[Gostev]

I can say that clean Windows server install (built-in firewall enabled) can be added to Veeam without any changes required. This is how we test the product. Looks like this install is not "clean". May be antivirus, or some custom security/firewall settings are blocking RPC.

Try disabling the firewall and antivirus, adding the server, and enabling the stuff back.

If it does not help, contact our support and do a webex with them - may be they will be able to spot something.

[msullivan@csa1.com]

Hello

Were you able to determine a solution for this error?
We have Veeam 6 installed on a host server running 3 vm's.
Firewall is off and Antivirus disabled, and we recieve the same error.

[Vitaliy S.]

Matt, if OP doesn't respond, please reach our technical team, as it is hard to troubleshoot technical issues via forums without seeing full log files. Thanks!

[collinp]

Does anyone know if it is possible to backup a Hyper-v 2008 R2 cluster that resides in a different domain than the domain that the Veeam Backup server resides in? I am not sure if my isssue is a firewall issue or a cross-domain issue. The situation is as follows. Our Veeam server is in our internal network on an internal domain. The Hyper-v cluster is on a separate domain on a separate network. We have allowed ports through the firewall for the VMM and Hyper-v hosts to communicate to the Veeam backup server based on the Hyper-v User guide (22, 135, 137-139, 445, 2500-5000, 6160-6190, 8100).

I was able to create a Veeam Backup job pointing to the VMM Server and I was able to add all vm's to the backup job. When I try to perform a backup on any of the vm's, I get the following error on each vm backup: "Task failed Error: The RPC server is unavailable. (Exception from HRESULT: 0x800706BA)".

Instead of trying to add the vmm server to the job, just for testing purposes, I tried to add a single hyper-v host to the job and went through the backup wizard for a standalone Hyper-v server. Here is the error message I got this time "Unable to connect via WMI. Hostname: [testserver] Server 'testserver.xx.lcl' does not exists or access denied. Check firewall settings. The RPC server is unavailable. (Exception from HRESULT: 0x800706BA). So I wasn't even able to create a job when trying to create a standalone backup job whereas I was able to create a job when pointing to the vmm host and was able to enumerate the vm's. I have tried to create the jobs with both the local administrator account of the vmm and hyper-v hosts and with a admin domain account in the hyper-v domain.

I then ran wbemtest from the Veeam backup server and tried connecting to the hyper-v host \\testserver.xx.lcl\root\cimv2, and I get the same error as when I try to add the standalone hyper-v server to a job "Number: 0x800706ba Facility: Win32 Description: The RPC server is unavailable.

I am now thinking that the veeam backup job requires wmi and that wmi can't query machines across domains. Anyhow, I know that I can just install a Veeam backup server or vm in each network and be done with it, but am still curious what is causing these issues. One other thing. The windows firewall has been turned off on the hyper-v hosts and the vmm server.

[foggy]

Collin, answering to your main question - yes, VBR can backup VMs running on hosts belonging to different domains. You're right, VBR requires WMI connection to the host to backup VMs that reside on it and it seems that your environment does not allow this connection for some reason.

VMM is used for getting the cluster configuration only, that's why you could successfully add it to the UI and create a job. But to actually backup VMs, VBR requires direct connection to the host (which name is discovered through VMM) to get VM properties, etc.

[collinp]

So this may not be a Veeam issue as much as it is a wmi issue across domains but perhaps there are some people in this forum that have experience troubleshooting issues like this. What would be the best tool to use to watch the traffic between the Veeam backup server and the Hyper-v Host to determine what would be blocking wmi from querying the hyper-v host. Would I use a sniffer? I know netstat can show the firewall port activity. I am not sure what other factors come into play when querying across domains. In my tests I have tried using local accounts that are common to each server and a domain account that is an administrator on the hyper-v host. I can map to c$ on the hyper-v host, rdp, ping, etc across domains.

[collinp]

One thing that I am seeing from performing netstat on the hyper-v host is that the Hyper-v hosts have a dedicated nic for CSV traffic. This nic is on a private network. Since CSV traffic is on a private network, the Veeam backup server does not have access to this network. I don't think this matters, but I am still investigating.

[collinp]

When backing up through a Checkpoint firewall, a portion of the Hyper-v Veeam backup traffic is seen as a threat, particular relating to RPC. See checkpoint knowledgebase article SK-454561 for the solution.

[foggy]

Colin, could you please share the direct link as I cannot find the article you are referring to (they have 5-digit article numbers on their support site). Thanks!

[collinp]

I asked the person who manages our firewall the reference id to the correct checkpoint firewall kb and he isn't able to find the original kb that he found when troubleshooting this issue. The bottom line is that our firewall was blocking some RPC traffic and that was the reason for these errors - not only Veeam RPC traffic but other RPC traffic as well.

When we were having problems, I ran netmon while running wbemtest. Wbemtest was pointing to \\RemoteServerIP\root\cimv. When the RemoteServerIP was within the firewall, wbemtest connected successfully and netmon showed both a 'syn' and 'ack' under the wbemtest.exe process. When the RemoteServerIP was outside of the firewall in question, wbemtest did not connect successfully and netmon showed a 'syn' but not an 'ack'.

[Ultra_Cool]

When I try to add a Hyper-V host, I receive the error "Unable to connect via WMI. My another hyper-v server is in workgroup and on different network. How can I make this working without vpn? My firewall is off and i still can't add my hyper-v.

[allixotech]

We found a fix for our particular version of this problem - it was a time issue. Make sure the time on all servers involved in your backup process (not guests) have their time synced with a DC or internet source.

[amaclellan]

Just want to reply to this thread for future users.

It's DNS.

It's always DNS with cross domain stuff like this. Either update your internal DNS servers with a static entry to the remote host and IP, or edit your local hosts file on your backup server.

[Nikolay]

Hello,

After upgrading two our standalone Hyper-V Windows 2012 (not R2!) hosts from B&R 6.5 to B&R patch 3 replica jobs end up with warning : "Failed to connect restored VM to the network Details: The RPC server is unavailable. (Exception from HRESULT: 0x800706BA)"
Firewalls are disabled on both hosts. No other changes were made before, during or after the upgrade. Backup jobs still run without any notifications.
Please help.

Thanks,
Nikolay

[Vitaliy S.]

Nikolay, I'm not sure your error is related to OP issue, so it's hard to say what is wrong without reviewing full log files. Please contact our technical team directly to troubleshoot it, as it is advised by our forum rules.

[D.Sargent]

Hello,

After upgrading two our standalone Hyper-V Windows 2012 (not R2!) hosts from B&R 6.5 to B&R patch 3 replica jobs end up with warning : "Failed to connect restored VM to the network Details: The RPC server is unavailable. (Exception from HRESULT: 0x800706BA)"
Firewalls are disabled on both hosts. No other changes were made before, during or after the upgrade. Backup jobs still run without any notifications.
Please help.

Thanks,
Nikolay

Nikolay,

Were you ever able to get this resolved? I have had the same issue since upgrading to V&R 7.

Thanks!
Darren

[veremin]

Since Nikolay has never come to update the topic with support ticket number, we cannot track the case and provide the found resolution. So, please open your own ticket with support team and let them investigate it directly. Thanks.

[wilsonchua]

We too have the same issues. Even with or without Windows 2012 R2 firewall turned or off, the VEEAM server fails to add the hyperV in another IP block.
I looked at the pfirewall.log and the syslogs and there are no entries there. Not even a "DROP" or "ACCEPT" message from the said IP address of the VEEAM.

It looks more like a VEEAM issue than a Windows 2012 R2 issue.

[veremin]

Hi Wilson, what is your support ticket number? Thanks.

[wilsonchua]

I haven't gotten a support ticket. We are running the FREE edition and may not be entitled to support.

[veremin]

According to our policy , customers even with Free version (let alone evaluation period) are eligible for support. So, feel free to contact them. Thanks.

[wilsonchua]

Hi v.eremin, I have gone and created a ticket 00621496 for this.
Also, both servers have the same time zone, and time settings.

[wilsonchua]

Thanks for the help, support. The solution was to create a VPN tunnel between the two servers. Then add the server using the PRIVATE IP address. I can now add the hyperv in one subnet to the VEEAM in another subnet

[veremin]

Thank you for coming back and updating the topic with the found resolution. We do appreciate it.