I needed to backup the complete server because of an SAN firmware upgrade. This just to be save and to prevent data loss. You could do a running backup but most backups are still better and smaller when the VM is powered off.

But after the powering off of the servers the Vmware Data Recovery stopped working. Every backup failed with the error: "error -3948 ( vcb api exception)".

I feared that something like this would happen because all our DNS servers are virtualised and so they were off. Basicly VDR needs to resolve the esxi servers name to an ip.

Solution:

1. Have a running dns server!
2. Edit the /etc/hosts files on the VDR.

1. Have a dns server running.

You could use a spare pc to run a temporary dns server. Or just keep your dns server running.

2. Edit the /etc/hosts files on the VDR.

Connect using ssh(*) to the VDR or use vsphere console.

Log in as "root". Default VDR password is "vmw@re".

Type the following command:

vi /etc/hosts

Add all your Esxi servers and infrastructure servers. So the file looks a lot like this:

127.0.0.1  DATA-RECOVERY localhost
192.168.1.1     esxi1.mydomain.local esxi1

Replace mydomain.local by your domain and esxi1 by your Esxi hostname.

Test if it resolves by giving the following command:

ping esxi1

If it pings then you did everything correct else your hosts file is not correct.

A good ssh program is putty