Odd Hotadd Proxy behavior

[ChuckS42]

I have noticed some odd behavior with my VA proxy servers (using Hotadd).

Scenario:
Veeam B&R version 8, latest update.
A vSphere 5.0U3 cluster with 8 hosts. Latest vCenter 5.0 build. All fully updated.
Dell/Compellent storage backend, iSCSI-connected.
Each host has its own Veeam Proxy server (to distribute the I/O load), built to Veeam specs (e.g., automount=diabled).
Each proxy server is configured to be in Virtual Appliance mode, with Network mode fallback.

Take a VM that has, say, 12 virtual hard disks. It's in a backup job that's configured to auto-select proxy servers. The job runs, proxy servers are assigned to virtual disks. Veeam sends the commands to vCenter to attach the disks to the proxies. All normal so far. However, what actually happens with the proxies is that *all* the VM's virtual disks are mounted to *all* the proxies, rather than just the disk the proxy is assigned to back up. I verify this by hitting Edit Settings on each of the proxies in vCenter and noting all the extra disks. Now, the backup job runs fine, but after the data has all been copied to the repository, it takes a very long time for each proxy to have the disks removed, around 5 minutes for each "reconfigure virtual machine" task, and they run one at a time.

I have verified the same behavior exists for Replication jobs.

Now, I have a separate environment, configured very similarly, but running vSphere 5.5U2 instead. Over there I see none of this oddness. Over there the proxies only mount the disks they've been assigned, not all the disks.

I don't know when this behavior started; I only recently noticed it, but I'm fairly certain it hasn't been happening the entire time I've been using Veeam (going on two years now).

Has anyone else seen this?

[alanbolte]

This is explained in release notes for VDDK 5.5.
"Rather than HotAdding all disks at connect time, as in earlier VDDK releases, in VDDK 5.5 each disk is HotAdded at VixDiskLib_Open() time, followed by reconfiguration for the disk."

Veeam B&R will use VDDK 5.0 for older vSphere environments, and VDDK 5.5 for vSphere 5.5.

Although Veeam B&R v8 no longer uses VDDK for actual read and write of hotadded disks (as in previous versions), we still use it for beginning and ending the backup.

[ChuckS42]

Ah, good. Expected behavior = no more troubleshooting. Thanks!