9.1.1 Can you have iSCSI device and SMB same ZFZ vol

[berrick]

FreeNAS-9.1.1-RELEASE-x64 (a752d35)

I moved an iSCSI target which was using a mirrored pair on there on controller to part of a zvol which also had a dataset used for CIFS. This all appeared to work OK time I did a large data transfer then I got lots of errors

istgt_lu_disk.c:4130:istgt_lu_disk_lbwrite: ***ERROR*** lu_disk_write() failed

What I was trying to achieve is both shares and iSCSI having part of the 4TB vol.

So is this config legal or is there a better way to do this?

Many thanks

 

[cyberjock]

No clue. Please read the forum rules and provide the information that you are supposed to provide when creating a thread.

Thanks.

 

[berrick]

Sorry cyberjock, the first post does, imo provide all the information required according to the rules as this is not meant to be a failure posting :). It was written in hast and perhaps isn't very clear what I'm asking. I am not after help currently, for the error I received, it was included for information. I was trying to ask a general question about Freenas (regardless of hardware) in case I was attempting something which just isn't possible. The question being;

Can (I hope I get this right, I dont want another spanking from cyberjock ;) ) an iSCSI target, folder base extent and a ZFS data set exist on the same ZFS raid and work without error. In this case the raid consists of three 2TB Seagate disks?

If the answer is NO not possible I wont continue.

If the answer is YES but hardware and Freenas version dependant or I wouldn't do it even though you can because..... then explanation and/or links to relevant information would be gratefully recieved. If the answer is in your great ppt "FreeNAS Guide 9.2.1" let me know where? as I haven't finished reading it yet.

FYI,
The way I was trying to achieve this was as follows /mnt/NAS 3 disk 4T raid. /mnt/NAS/Media being a dataset 3.5T in size. The remaing space I allocated to an iSCSI extent here /mnt/NAS

I did read another post about the this issue using an earlier version of Freenas but the question I ask here wasn't answered on that post.

AMD Athlon(tm) 64 X2 Dual Core Processor 5200+
Memory4075MB

 

[jgreco]

AMD Athlon(tm) 64 X2 Dual Core Processor 5200+
Memory4075MB

You need a bare minimum of 16GB for iSCSI to have any reasonable chance of success.

RAIDZ and iSCSI are not good bedfellows.

You have a 4TB pool and 3.5TB is used, the way I'm reading what you've said. You then tried to give the remaining 500GB to iSCSI. This doesn't work. Your pool is already full; a ZFS pool should not be pushed past 80% capacity. A pool with iSCSI on it should not be pushed past 60% capacity, generally speaking.

Your posts don't provide much insight or clarity into what you've got and what you're trying to do; when you come someplace asking for help, follow the forum rules regardless of whether or not "imo" you've provided enough information.

 

[berrick]

RAIDZ and iSCSI are not good bedfellows.

Fantastic, thanks for the reply jgreco this is what I wanted to know :) So I wont attempt do it that way, I will create a seperate volume for iSCSI. I will keep in mind the min 16GB ram recommendation.

Your understanding of what I tried is pretty much correct. I wasn't aware of the 80% capacity of ZFS pools though. Great info. What happens if you go ever the 80% capacity??

Your posts don't provide much insight or clarity into what you've got and what you're trying to do

Please dont take this the wrong way I appreciate your time in replying but I deliberately didn't post the spec of the current freenas box, the spec isn't relevant to the question. What I was trying to do (one raid volume with both iSCSI and data set used for CIFS) isn't relvant either now as you have pointed out its not a good idea :)

This freenas box is a test rig whilst I get to grips with this great product and work out want I want to do. I threw it together out of stuff I had lying around, i know its way underspec'ed but it works and works well for my use.

Thanks again for the reply

 

[Bidule0hm]

"What happens if you go ever the 80% capacity??" The whole universe implodes... :P

More seriously: ZFS use CoW (copy on write) who needs some free space to avoid fragmentation. The more you fill the pool the slower it'll get ;)

 

[zambanini]

berrick, after 80÷ your freenas appliance will hire a killer for the former owner of it.

 

[jgreco]

Fantastic, thanks for the reply jgreco this is what I wanted to know :) So I wont attempt do it that way, I will create a seperate volume for iSCSI. I will keep in mind the min 16GB ram recommendation.

Actually we'd recommend more than that. Block storage on a CoW filesystem is stressful.

Your understanding of what I tried is pretty much correct. I wasn't aware of the 80% capacity of ZFS pools though. Great info. What happens if you go ever the 80% capacity??

Fragmentation. And that's for normal file storage. For iSCSI, that number is lower. See https://forums.freenas.org/index.ph...res-more-resources-for-the-same-result.28178/

Please dont take this the wrong way I appreciate your time in replying but I deliberately didn't post the spec of the current freenas box, the spec isn't relevant to the question. What I was trying to do (one raid volume with both iSCSI and data set used for CIFS) isn't relvant either now as you have pointed out its not a good idea :)

And that's your error; it really IS relevant. Just because you think it shouldn't matter doesn't mean it actually doesn't matter. First off, you run a fairly good chance of being ignored by those who could offer you insight, because you've not followed the posted rules that we wrote after the 999 people before you who felt just the same way about the relevance of their hardware specs not mattering to the question actually resulted in lots of extra work for us, dragging the information out of the user, only to find out, oh, yeah, well, it does actually matter.

We're volunteers, we're not paid by iXsystems to support users on the forum. Make it easier for us to help you by doing what's requested and expected.

 

[cyberjock]

Please dont take this the wrong way I appreciate your time in replying but I deliberately didn't post the spec of the current freenas box, the spec isn't relevant to the question. What I was trying to do (one raid volume with both iSCSI and data set used for CIFS) isn't relvant either now as you have pointed out its not a good idea :)

Sorry, but you are totally, 100%,incorrect. In fact, your specs *are* the problem. You don't even have the minimum!

You cannot test a product using hardware that isn't meeting the minimum spec and expect things to work right. PERIOD.

And again, when asking for help it is NOT for you to decide what you should or shouldn't share. That's the fast way to the ignore list for the 5-10 volunteers that help people here.

 

[jgreco]

Couldn't resist, huh.

 

[berrick]

Thanks for all the replies

The question I asked "can an iSCSI target be part of a zvol which also had a dataset used for CIFS" has been answered.

The answer is "RAIDZ and iSCSI are not good bedfellows".

There is no elaboration on the answer which implies this is the answer reqardless of the hardware spec you are running and was all I wanted to understand.

Yes my spec is less than the recommended 8GB minimum but the way I read the manual you can run with less but have to except that good performance and stability may suffer. I except these facts

You cannot test a product using hardware that isn't meeting the minimum spec and expect things to work right

I agree BUT i never said I expected it to work right.

You learn more about a product when things go wrong than when the just work and regardless of whether my spec are less than the recommendations so far it has just worked and that I hold as testiment to the hardwork of all involved.

I think you volunteers do a fantastic job and am grateful for your advice.