Uncovering the Truth about HBAs and SMART data

[@livewiretechnicalservices8307]

Excellent info! Thank you for clearly articulating the problem. Finding good content like this is so refreshing. I uncovered this same info when I was trying to figure out why I couldn't get SMART data in FreeNAS on my non-IT mode H310. Once I figured out how to flash it to IT mode and read through the pages describing the process I found the info about the driver. I'm looking forward to more content from you! Thanks again!

[@ArtofServer]

Thank you!

[@edbouhl3100]

SO glad to get this straightened out! I have a R320 server with an H200 raid card and I was seriously considering flashing to IT mode.

[@ArtofServer]

An H200 in a R320 seems like a non-factory configuration. For R320, you should consider using one of the mini monolithic cards. If you don't need RAID, there is still an advantage of using the LSI IT mode firmware on the Dell PERC H200/H310 cards, they increase the queue depth as Dell's firmware cripples it, probably to prevent these products from cannibalizing the higher end H700 since these cards can actually perform really well. Just food for thought.

[@edbouhl3100]

@@ArtofServer Thanks for the detailed comments - I learned quite a bit. I also realized that I was thinking of my T110, not my R320 (which has an integrated raid board). Sorry for the mixup.

[@sahlind]

Very informative. Such a world of difference when you have the time to rtfm and know what you're doing :) Thanks for sharing.

[@giornikitop5373]

very informative. so, freenas devel team instead of fixing the bug and updating their drivers/utils/os etc, they just went with the "modern" solution, "don't use raid controllers" when this is clearly not a hardware problem. ok god to know. just wait till ppl start using nvme for their storage and then wonder why the performance is so so bad. freebsd is very behind in supporting new drivers, new schedulers and bleeding edge hardware. i think amazon aws had their first series problems with nvme performance. this will be fun!!!!

[@NdxtremePro]

All right, the smart data isn't why you don't use zfs with raid. For example, most drives use either 512 or 4096 sector sizes, while raid will expose an emulated sector size. (My Perc 6/i in single drive raid 0 defaults to a 64k size, and I have to change it to the lowest of 8k sector sizes. I then need to pass this info to zfs, which isn't really optimized for that size. ) This is one example of the issues associated with doing this.

[@jamesklinger1039]

This was SUPER HELPFUL! I have a H700 with all my drives in a raid 0 vitual disk for each physical disk. I had tried the normal smartctl commands in TrueNas as well as the gui with negative results. Now i know i have to use the proper commands to get that smart info and ill be fine. Only question i have to ask. With this setup do i have to worry about rebuilding a failed drive when that happens. I mean will i beable to pop in a new drive make sure its initialized on the raid controller and import it into the data pool to replace the failed drive without issue?

[@ArtofServer]

If using single-drive-raid0 setup, you may have to run some MegaCli commands to setup the replacement driver as single-drive-raid0 again. I don't know about FreeBSD/TrueNAS, but with Linux, that should be automatically detected and able to import to ZFS pool or add a replacement drive to resilver. With FreeBSD/TrueNAS, it might not work the same way.

[@arindambanerjee1662]

Nice to know 👍

[@ArtofServer]

Thanks for the visit

[@ralphm6901]

Never mind accessing SMART data, I have an R420 with an H710p Mini and it wouldn't access 8Tb drives. I flashed it to IT mode last night and it works with 8Tb just fine now.

[@ArtofServer]

Actually, the only thing you really needed to do was update the Dell firmware and it would have worked fine. But if you wanted IT mode, then yes of course that would be the way to go.

[@ralphm6901]

@@ArtofServer that's good to know. However, I just flashed back to 21.3.5-0002_A09, which Dell says is the latest version, and I have 3 x 8Tb drives showing "blocked" in the RAID configuration utility. If you can point me to a newer version, I'd be happy to try it.

[@Magnus_E]

Most awesome ebay seller indeed. I want to buy a server so I can buy a card from you! :D:D:D *** I can buy without even using a server but let's not be excessive... ahhaah

[@ArtofServer]

Ha ha ha... thank you. You humble me. I appreciate your support! :-)

[@dorinxtg]

Great video! I'm using M1015 megaraid card without changing it to IT mode and without defining any disk - it simply shows in the boot the disks as "JBOD disks" On FreeNAS latest it is indeed using the MFI driver and smartctl shows everything. One thing that I didn't see in your video: in IT mode, does FreeBSD and Linux shows the full output of smartctl for the drives?

[@ArtofServer]

In IT mode, yes SMART data is accessible, it's just not the only way. Thanks for watching!

[@arubial1229]

Always run ZFS in IT mode, you'll thank me later. Running FreeNAS in hardware RAID mode will work until it doesn't and then all your data is gone.

[@ArtofServer]

@@arubial1229 I'm actually planning a video about that topic. coming soon...

[@johngrabner]

Lots of people say truenas scale not stable in jbod mode. Can you do a video on jbod mode vs hba it mode. To sounds the same.

[@ArtofServer]

Often times, the term "jbod mode" is the same as "IT mode." And for the most part, it works the same. Some HW RAID controllers have a "JBOD mode" that you can enable. I've even used Hardware RAID controller in "single disk raid-0" to do ZFS. Checkout the "Forbidden Arts of ZFS" series on my channel.

[@0ChAnTi]

Another lesson learned

[@artlessknave]

/dev/bus/0 would be the mask I think, and does obfuscate the way to get the smart data. that...quote very much looks like its from the freenas forum, and they ...definitely tend to just simplify things. for example, instead of explaining the correct ways that you *could* use SAS1 controllers, they would just say "do not use sas1 controllers", or "do not virtualize freenas unless you already know what you are doing". same thing with RAID controllers + zfs; there are cases where, if configured correctly you could use them, but so many ppl kill their pools, and then go to the forums in desparation because they don't know what they are doing, that it is safer to just blanket exclude them and avoid the hassle entirely, particularly because some raid controllers add extra stuff to the disk in "jbod or raid0" modes, that mangles the data on those disks if used with other controllers (hp). zfs does not care that you lost your mothers pictures because you didn't have a proper back, or were using IR instead of IT, and looks on indifferently as you struggle to learn what you did wrong.

[@marjanzupan8017]

Is there a way to get S.M.A.R.T data in freenas for SAS HDD?

[@ArtofServer]

yes, more or less the same way as SATA HDDs. but you should know that SAS and SATA have different types of SMART data; it's not going to be the same.

[@AhmedMohamed-xs5ij]

Amazing

[@ArtofServer]

Thanks