Docker is a great solution to create Microservices to reduce the footprint about deployment, management and security. The logic around the container is that I can create a new image in a couple of seconds and this could mean no backup. More or less is correct but without a backup, in case of failure from Container Host you should reinstall everything.
So the backup is important in any case! As you probably know, Docker is also available in Windows Server 2016 (more details here) but if you plan to protect these machines with Veeam Backup & Replication, keep in mind that you could have issues. In particular, the indexing take too much time to analyze the guest machine.
As you can see from figure 1, the process was active for over 9 hours.
Figure 1 – Index Process
This is not the only problem because I discovered a grow of guest vhdx to over 95GB – figure 2.
Figure 2 – VHDX Disk
With the great tool WinDirStat, I found some files into ProgramData/Veeam/Backup folder dedicated to VeeamGuestIndexer and the dimension was not normal – figure 3.
Figure 3 – Guest Disk Analysis
I don’t know what is the reason but I suspect a redundancy because into the Container Host there’s another folder with Windows Server 2016 (is called Docker Image).
To resolve this issue, I had removed these files from guest machine and I disabled the indexing into Backup & Replication, as showed in figure 4.
Figure 4 – Workaround
I cannot confirm if is a known issue but I found this problem into two different machine protected with Backup & Replication v9.5 (with and without Update 1).