Please do not run FreeNAS in production as a Virtual Machine!

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TXAG26

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My response was a little tongue in cheek. ;-). If people aren't going to follow the required steps to properly virtualize their setup and when they've been beat over the head by what could happen, even with a properly virtualized setup, when things go sideways, I just don't feel bad for those folks.

Let me state this again for the thousandth time - Always have a current backup of all of your data (especially if virtualizing).
 

jgreco

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Do you know how many people lost their data after they were also 100% sure the system was rock solid and safe to store the only copy of their data? Every. Single. One.

A bit exaggerated there, huh. I mean, you wanna say it's risky, fine, great, it is. But virtualization is not a guaranteed death sentence for your data.
 

anodos

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A bit exaggerated there, huh. I mean, you wanna say it's risky, fine, great, it is. But virtualization is not a guaranteed death sentence for your data.
What hyperbolic language from Cyberjock???!!! Never! :)

Seriously though he said:
(1) "all people who lost their data were sure they were safe" (all A's are B's)
not
(2) "all people who were sure they were safe lost their data" (all B's are A's).

Granted (1) is false. There have been times that I intentionally did stupid things knowing they were risky and lost data.
 
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jgreco

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Well, I read it as (2), but I can meet you halfway and agree that the sentence in question is dreadfully atrocious.
 

9C1 Newbee

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The guys nuts! Grab'em.
 

Ericloewe

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messerchmidt

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is the developer teaming working with vmware and/or M$ to try to get freenas working perfectly under their hypervisors?

or will we have to wait for Freenas 10.x?
 

jgreco

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FreeNAS works fine under a hypervisor. The problems are when users try stupid virtualization tricks. It becomes real easy to lose your data. Not a FreeNAS problem, not a VMware problem. Strictly a user expectations thing.
 

9C1 Newbee

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That sounds kinda bad.
Over the years, you are the first person to ever get it!

Another one nobody gets is my Lowes/Home Depot joke I like to play at the register.

Sir, did you find everything ok?
Yes, but I have a few questions about the blind cutting area.
What is your question?
Does moping up the blood suck?
What?
Do their dogs try to bite when you cut them?
Sir, I can have a blind cutting specialist come talk to you if you wish.
That won't be necessary. I will be paying with credit and using my military discount today. :(
 

messerchmidt

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FreeNAS works fine under a hypervisor. The problems are when users try stupid virtualization tricks. It becomes real easy to lose your data. Not a FreeNAS problem, not a VMware problem. Strictly a user expectations thing.

would it be possible for you to elaborate? what to do? not to do? etc - maybe a new sticky? I am not an IT admin, I just follow guides (bought hardware based on the guide,etc).

The new system I got is a 2130v3 with 32gb ecc ona supermicro board. Being able to run a windows 2012 server on the same machine in a safe manner would help me by not needing to add additional machines,etc
 

Tywin

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would it be possible for you to elaborate? what to do? not to do? etc - maybe a new sticky? I am not an IT admin, I just follow guides (bought hardware based on the guide,etc).

I don't feel bad about linking to @jgreco's existing post, because you would find it in 2 s if you tried to search for it. That said, based on your own self-description, I would think twice (or three times) about trying it. It is not complicated when you get down to it, but it is definitely one of those things where you need to have a solid grasp of everything that's going on. Blindly following guides is akin to using dead reckoning for navigation -- it's OK to get to your nearest Home Depot, but it's not going to help you fly an airliner across the globe.
 

messerchmidt

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I don't feel bad about linking to @jgreco's existing post, because you would find it in 2 s if you tried to search for it. That said, based on your own self-description, I would think twice (or three times) about trying it. It is not complicated when you get down to it, but it is definitely one of those things where you need to have a solid grasp of everything that's going on. Blindly following guides is akin to using dead reckoning for navigation -- it's OK to get to your nearest Home Depot, but it's not going to help you fly an airliner across the globe.

Not everyone here has a computer science, IT, etc background. We follow guides created by others who know a lot more than end users.

A guide of best practices, and a negative guide of what not to do (Specific "stupid virtualization tricks", pitfalls, etc) would be useful. Add a warning at the beginning and be done with it. In the Hardocp forum and other forums, quite a few people seem to be running it in VM without issue. By the picture posted of their hardware, the hardware used,etc - these are most likely sophisticated users. They know how to do it properly, much like, jgreco and others, while I do not. I depend on their shared know how. The parts I picked for my latest build were selected based on guides in this forum for same.
 

jgreco

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@Tywin said it well in #117. Guides don't really cut it. If you can read my existing post on the topic and you can say "well duh that makes complete sense", then you might be able to pull it off with minimal risk and I am certainly willing to give you my blessing to try, with the caveat that you're an adult and responsible for your own actions and a reminder that my blessing means nothing, heh. That post is general advice about obstacles to virtualization written for people who are experienced with virtualization. At first glance it is easy to say "oh just another VM" but a proper FreeNAS deployment has some significant divergence from being just a typical VM.

and a negative guide of what not to do (Specific "stupid virtualization tricks", pitfalls, etc) would be useful.

That would be the first message in this thread.

Look, the fundamental problem here is that there isn't really a safe way to teach magic to users. Early on, I spent some time trying to work with Cyberjock on virtualizing with some less-than-ideal hardware. It failed, or rather, it worked for a little bit, then failed, but the thing that was a saving factor was paranoia. We identified that the system wasn't stable and he was willing to accept and understand that and STOPPED TRYING. He then proceeded to do his thing by doing a deep dive into the topic and figuring out what he needed to do in order to make a workable system, and I believe he now has a virtualized FreeNAS system that he is happy with, on better hardware. Awesome. His willingness to sink his teeth into a topic and then not let go until he's beaten it is the sort of quality you need to have success.

But it is risky. As an example, I downed a virtualized filer here to do a network card swap and when it came back up, it had renumbered PCI ... silently invalidating the PCI passthru configuration. I got a very, very chilly feeling for a few moments when the FreeNAS VM refused to come up. Unexpected side effects are a sysadmin's nightmare. They can be benign, but they can also be way bad.

In the Hardocp forum and other forums, quite a few people seem to be running it in VM without issue. By the picture posted of their hardware, the hardware used,etc - these are most likely sophisticated users. They know how to do it properly, much like, jgreco and others, while I do not.

So there's a few possibilities there. Not all are happy.

1) It is completely possible that these people have followed my virtualization recipe, which Tywin already pointed you to.

2) It is completely possible that they've done something hacky, like using RDM. The experience we've had here in the forums is that this can go wrong very quickly, and then users don't know how to recover. So:

2A) Maybe things go wrong and they know how to recover. Great.
2B) Maybe things go wrong and they're owning the failure and loss. Sad but I respect that.
2C) Maybe nothing goes wrong. That's not what we've seen here but it may be related to clue level. Great.

3) It is completely possible that they're using FreeNAS as a VM serving data off an ESXi datastore, which comes with lots of possibly unexpected caveats but is expected to generally work.

3A) If the datastore is nonredundant, then a problem with the datastore (disk loss) is likely to hang the FreeNAS VM. Not great behaviour for a filer.
3B) The obvious configuration of making a single data disk is a bad idea; ZFS has no place to recover bitrot from. Two virtual data disks mirrored on a redundant datastore is ideal and I bless it with my stamp of approval. Of course, you're using a LOT of disk to provide that pool, but the VM is going to pick up the reliability characteristics of the underlying datastores and enhance them with bitrot detection too.
3C) The bad configuration is to configure a bunch of nonredundant datastores and then make a bunch of virtual data disks on them and run ZFS in RAIDZ on top. This will seem to work great but suffers 3A) and seems to have some other issues as well if recovering from failures.

Definitions of "properly" vary widely and there's no single correct route. These are not all the possibilities, even.
 

cyberjock

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I'm not virtualizing anymore. I stopped about 6 months ago because the risk wasn't worth the benefits. It got harder and harder to see everyone losing data and then go to sleep at night knowing that I'm using an almost identical setup. One person that lost their data was identical to mine except for the PSU and RAM.

That server was like what most people around here do. They have some important data backed up, but the largest part (my blu-ray rips that have taken years to rip, reencode, etc.) wasn't backed up. I was no longer willing to risk having to pull out those disks from my basement and do a re-rip "just because I wanted FreeNAS in a VM". Sorry, the benefit just didn't outweigh the risks for me.
 

9C1 Newbee

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I have a box for FreeNAS. I have a box for virtual machines. It would be really cool to have it all on one box but not at the expense of my data. I think I would be better off with a microsoft solution if I wanted to roll the dice.
 

anodos

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I have a box for FreeNAS. I have a box for virtual machines. It would be really cool to have it all on one box but not at the expense of my data. I think I would be better off with a microsoft solution if I wanted to roll the dice.
Honestly I don't like virtualization because it reduces the number of blinky lights - the real reason I got into computers.
 
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