Problems with the commercial Hyper-V backup client

client
1

Hey so I have two Hyper-V’s running, replicating each other using the Microsoft Hyper-V replication.

I’m using the commercial Hyper-V Urbackup Client.

I have three Urbackup servers running, one only backing up my first hyper-v, one only backing up my second hyper-v and one backing up both (first and second hyper-v) to a external drive.

When starting a Backup for a VM on the second Hyper-V via the Interface, it just says “Starten der Sicherung fehlgeschlagen” without any error code. The first hyper V backs up just fine.

Looking at my server_idents, there is one (of two) idents that is the same on Hyper-V 1 & 2, that seems to be my external drive urbackup server.

Because the VM’s are getting replicated, they also have the same hostname, maybe that is part of the problem?

Server logs (clean start with debug options, then started backup via Interace):

It also says this even tho that VM is running:

2026-04-20 11:52:07: Sending Identity to client “Hyper-V2025-2[PPCOBRA]” failed. Retrying soon…
2026-04-20 11:52:09: Forcing offline client “Hyper-V2025-2[PPCOBRA]”

Client logs from second hyperv (with debug options):

Thanks in Advance :slight_smile:

2

Sorry for the late answer.

Unfortunately could not download the debug log file anymore (link expired).

From the description and the server log file I’d guess it is just UrBackup - Frequently asked questions . You could confirm by enabling the “Status” column on the server where it does not work.

The fix would be to add the server identity to the file.

3

Hey, thanks alot for your answer.

The debug log doesn’t seem to be expired.

When activating the “Status” column, I can see that my Hyper-V says “ok” while the vm’s all say “Starting up client”. My server idents seem to be correctly set, I’ve also removed and readded them already.

Edit: when i look on my other urbackup servers, “Status” shwos “ok”, also for the vm’s

Greetings

4

Weird, downloading the log seems to work now.

But the message I see there is consistent with what I posted:

2026-04-20 14:24:23: ClientService cmd: #ImGDb3QDD5mRdUMbwGE9m#ADD IDENTITY
2026-04-20 14:24:23: Rejected server identity mGDb3QDD5mRdUMbwGE9m

The client rejects the server, because it is not listed in the server identity file.

5

I have three servers running, this is expected (and correct) from my understanding…

First server backing up my second Hyper V(OF0uXlUANbsAZssfFfq5)

Second server backing up my first hyper-v (ImGDb3QDD5mRdUMbwGE9m)

Third Server backing up both hyper-v’s to an external drive (4y6bi7PZJhhOO9hyLO35)

So that identity should be rejected, as it shouldnt back up to that server.

I’m experiencing my Problem on the third Server, the server identity is set correctly in the txt file (straight up copy paste from the interface)

6

Could you perhaps tell me the server identity of the server that does not work?

7

This one from the third urbackup server

8

Just looked into the webinterface - now the third server stopped doing backups altogether. It worked for my first hyper-v some time ago.

Logs from today:

https://privatebin.net/?e16091f7ff473d31#2CM8VrVxwjxJ1n4oHCo55HYjuSJpHcfooU4fkA1THSHG

9

Thanks! One theory I have is that the first and the second Hyper-V server have VMs with the same VM id.

If you send me your backup_server.db* files I can confirm this.

The third backup server would try and fail to rename the clients, because it assumes it is the same one. Logging in this area could be more verbose.

1 Like
10

Here’s a full copy of my server db. Thanks alot!

[link censored]

11

Can confirm. Seems changing the VM id in Hyper-V might be too hard, so this might not be a work-around.

Also I think it is a useful feature for if VMs are moved between Hyper-V servers.

So solution would be to add a (per-client) setting to disable client rename detection.

Also can confirm it is my ad-blocker blocking … questionable pop-ups… that made the link not work.

12

Thanks alot!

I work in an IT service provider business and we’re currently getting our customers to buy the Hyper-V client. We have multiple customers with the same constellation (two hyper’-v’s replicating each other and 3 urbackup servers).

Is there any deadline for this feature? We can’t really recommend the hyper-v client to our customers if the issue persists.

Sorry for the popups, I use an adblocker myself (uBlock Origin) and didnt see any ads/popups.

13

I added a setting in the advanced section to not detect the rename in 2.5.38: Index of /downloads/Server/2.5.38

After disabling the setting you’d need to either restart the server or take the client offline and online again.

14

Hey, just tested out the new release, works like a charm!

Thank you a lot for implementing this feature! We will start rolling out the update (and soon the hyper-v client) for our customers!

Grüße ausm Landkreis muc ;))