Looking to upgrade from FreeNAS 9.10.2-U6 to TrueNAS

[UncleFester]

Hello To You,

I am looking to upgrade from FreeNAS-9.10.2-U6 (561f0d7a1) to the lastest stable version of TrueNAS.
I've been trawling through the forums for advice on this and the information out there doesn't quite answer my questions and it's a bit fragmented, hence the post.
I've also noticed that people are getting into trouble trying to do this. So, before I do anything to my unsuspecting server, I was hoping for some good advice on how best to upgrade.

First some information. Hope this helps.

1. The pool looks to me to be unencrypted.
   • I determined this by using the zpool status command and the was no .eli exstension on the end of the guid.
2. My system specs are as follows:
   • OS = FreeNAS-9.10.2-U6 (561f0d7a1).
   • Processor = Intel Xeon E5-2620v3 1.
   • Motherboard = Supermicro X10SRH-CLN4 Single socket R3 (LGA 2011).
   • Memory = Samsung 8GB DDR4 2133MHz ECC Registered Server Memory -M393A1G40DB0.
   • OS HDD = 256GB Samsung 850 PRO 1.
   • Data HDDs = WD Red 4 TB x 8.
   • On board (no card) LSI 3008 flashed to IT mode.
   • UPS = Eaton 5SC 1000i 1.
3. I have no way to back-up the server at present.

Now to some of the questions I have.

1. Roughly how long would upgrading take?
   • The reason I ask is that I have limited time to complete this. A window of about 2 weeks. After that I must return to something I'm currently working on.
2. From what I can tell, the recommendation is to upgrade from FreeNAS-9.10.2-U6 (561f0d7a1) by switching trains within System>Update within the FreeNAS GUI to 11, performing the upgrade, then 11.2 and performing the upgrade, then 11.3 and performing the upgarde. At this point, it should be possible to upgrade to TrueNAS.
   • Have I got this correct?
   • Is there a better, safer way to upgrade to TrueNAS?
3. As I go through this process do I need to update the pool?
4. I vaguely remember having to update the LSI 3008 ROM each time I upgraded the FreeNAS OS, so that the FreeNAS OS version corresponded to the LSI ROM version. And that the version number of the LSI ROM was one below the FreeNAS OS version (e.g. FreeNAS version 10 requires LSI ROM version 9). If this was not done correctly, FreeNAS would warn the user with a red system alert light in the GUI and possible data corruption could occur. This was a long time ago now so it's all quite hazy.
   • Can anyone advise?
5. I am currently running one plugin within a jail. It's Transmission Ver2.93.
   • Should I turn off the plugin while I upgrade within the Plugins>Installed section of the FreeNAS GUI?
   • Do I need to upgrade the plugin after I perform each upgrade?
6. Is there anything else I need to do before or during the upgrade process to make the upgrade go smoothly?

That's all for now.
Thank you to anyone who takes the time to respond to my daft questions

Uncle Fester.