vsphere on nutanix, CBT .vnfs-*ctk*.vmdk hidden files

[ichi-ed]

Hi Everyone,
we have a strange situation with Veeam b&r on Nutanix&vSphere environment, Nutanix=NFSv3 datastore for vsphere. With each full backup, additional new hidden .vnfs*ctk.vmdk file are created for each vmdk file and are kept as long as the VM is powered on. We could live with this if it weren't for the fact that the number of files grows, since each full active backup means another new .vnfs*ctk file. Now we have thousands of these files. As far as I know CBT mechanism does not require the creation of additional ctk files for vmdk. Do you know where these files come from? Are they needed for anything?

Thank you for help!

[Gostev]

Hi, seems very strange indeed that you get new CTK files created each time CBT is reset but old ones are not removed. However, please be aware that Veeam does not control the technical details of CBT implementation (we're just issuing high-level VMware API calls and it's ESXi that creates and manages those files).

May be VMware has bugs with cleaning up some files, may be it's due to Nutanix. I recommend you open a support case with VMware, then if they find this behavior to be some Nutanix artifact then open a case with them as well.

As a workaround, you can try disabling CBT reset at active full in Veeam backup job settings. It's a nice precautionary measure for possible yet-unknown CBT bugs similar to ones VMware had previously, but it's not strictly required.

Thanks

[nathaniel.vignes]

hello,

any update on this issue ?
Same here, I'm contacting Nutanix for now, and keep you posted if something rise from this...

[Andreas Neufert]

This is a VMware issue not a Nutanix issue, please reach out to VMware.