Unbackupable file

This file inside this zip cannot be backed up as part of a “file backup”. The live log shows it at “54% finished 1.5 MB/2.75244 MB at 17.352 KBit/s” forever.
MicroXP.vdi.zip (366.8 KB)
It was originally a 2.5GB vdi, but I used process monitor to locate the exact section that it gets stuck on and extracted it. This 2.75MB chunk alone still triggers the issue.
Confirmed to occur on multiple (Windows) clients.
Additionally, the server “Stop” command has no effect when the client is stuck in this state.

Cannot reproduce the issue with your file. You’ll have to provide more details. See this post Having problems with UrBackup? Please read before posting

Another option is to send me a memory dump of a stuck client (like this: https://kb.sitecore.net/articles/758511 )

Ack, I was afraid of that. Must be environmental or configuration then. I’ll set up some VMs to isolate the condition.

Sorry to bump this 3 years later, but I didn’t want to leave this as an xkcd 979 moment, and I don’t see a way to edit posts. The issue turned out to be a buggy network switch, of all things.

I isolated a specific chunk of data that when sent over the network would simply not arrive at the destination. The TCP connection would get stuck in an endless loop of retransmission of this one packet, causing the entire backup to stall. And since the backups were neither compressed nor encrypted, this specific packet was guaranteed to show up in every backup attempt, specifically in that file. It only worked if I connected that PC directly to my server rack switch thus bypassing most of my network.

I swapped out one of my switches and updated the firmware on all the others and the issue disappeared.


Thanks for the update! That is a good story! And glad you managed to systematically track down the issue and find the cause :slight_smile: