VMware Consolidated Backup (VCB) was a first attempt by VMware to address the backup challenges of backing up VMs. However, it has significant limitations and has already been replaced by VMware. If you’re already using it, fine. But why would you move to it NOW?
VCB is short for VMware Consolidated Backup and the idea behind it was simple. Solve the I/O problem of VM backup by moving the I/O out of the ESX server and into a proxy server that can see the ESX’s server’s storage. However, a number of things happened along the way.
- If you perform the image-level backup (the only method that can be used to fully recover a VM), you have to copy the entire VMDK file from the ESX server’s storage to the proxy server’s staging disk every time — and then you have to copy it from the staging disk to your backup system. That’s a two-step backup every time.
- If you perform an image-level restore, it has to be restored to the VCB proxy and then imported into the ESX server. That’s a two step restore.
- If you try to perform an incremental backup of the image-level backup then you have to copy the entire VMDK from the ESX server to the staging disk and then do your incremental backup from there.
I ask in every TechTarget Backup & Dedupe School how many people have implemented VCB, and usually about 5% of the VMware users raise their hands. Then I ask how many of them say it solved the problem they wanted it to solve, and very few of them ever raise their hands.
The good news is that VMware has acknowledged this and completely re-architected the backup infrastructure for vSphere. VCB is still there, but only as a legacy way for backup software products that use VCB to connect to vSphere. But it is no longer how you backup vSphere. The new method does not have the limitations mentioned above.
But here’s the bad news. None — and I mean none — of the usual suspects (NBU, NW, TSM, CV, AS, DP, etc.) have ported to the new backup API in vSphere yet. Only the point products (ESXpress & Veeam) have actually ported to it. The bigger companies will be coming out with their versions in several months.
So here’s my question: Why would you bother installing VCB right now if you’re going to have to uninstall it and replace it in a few months? I don’t think you should. And I think you need to call your backup software representative every week and ask him or her when they’re going to fully port to vSphere’s backup API. Limp along until then as best as you can — or you can look at one of the point products that already fully support vSphere.
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Written by W. Curtis Preston (@wcpreston). For those of you unfamiliar with my work, I've specialized in backup & recovery since 1993. I've written the O'Reilly books on backup and have worked with a number of native and commercial tools. I am now Chief Technical Architect at Druva, the leading provider of cloud-based data protection and data management tools for endpoints, infrastructure, and cloud applications. These posts reflect my own opinion and are not necessarily the opinion of my employer.