vCenter Converter Standalone – Slow conversion rates and SSL

I thought I’d quickly write about this as it was something I was not previously aware of, mostly due to the fact that I have not performed many P2V migrations using the Converter tool and when I have it’s mostly been with the old offline converter.

Anyway, I was doing some bench-marking of the conversion process on a Windows 2003 R2 server and I couldn’t understand why I seemed to be hitting a network throughput ceiling of around 10MB/s. At first I though it must have been a routing issue as in this particular environment I was using had multiple VLANs and the source machine was in a different VLAN to the ESXi host. The router in this case only had a routing throughput of 100Mb/s so the 10MB/s made me think that this was the case.

However, when I moved the host into the same VLAN as the source machine I got the same speeds…now I was really confused. Everything else in between seemed fine and I could not work out what was making the conversion so slow.

So I jumped on Twitter to see if anyone else had come across this before (admittedly Google probably would have told me :-P) and a couple of smart guys i know @vStorage and @dmanconi suggested I turn off SSL.

I immediately went back to Converter and was clicking around like crazy and thought “where the hell do I turn that off!!??!!??”. Thankfully Google stepped in here and lead me to this VMware KB article:

Aha! So as of vCenter Converter 5.0 it enables SSL by default…I’m not sure why to be honest, in my opinion security of the traffic during a P2V would be the last thing on my mind, but that’s just me 🙂

Anyway, I followed the instructions and set the <useSsl> parameter to False, restarted the Worker service and kicked off my conversion again.

WOW, now I was getting around 50MB/s throughput on my conversion, around five times faster than before! This now meant that my upcoming P2V jobs were going to complete in way less time than I first though.

So a word of advice if you are thinking about doing some P2V’s or are not blown away by how slow they are running, apply this tweak and you will be away laughing.

Oh, while we are on the topic, for those of you using HP Proliant servers, Guillermo Musumeci has written a handy tool for automating the removal of the HP Proliant Support Pack drivers and software after you’ve done your P2V: …unfortunately at this moment the website won’t let me register, but I’m sure it will be working again soon. The tool has been around for some time but is one of those really hand tools to have and saves manually removing the HP drivers and services.