Timke

Oh and they RIPPP holy smokes. I'm seeing 270MB/s peak write speeds PER READ/WRITE HEAD! That's 540MB/s per HDD! how nuts is that?? Early SSDs weren't this fast myyy goodnesssss! Sustained they're around 260-265 write per head, so still 520 per drive. what on earth is this beast 💀

Hi there, it's been a while but i have good news for everyone who found this thread or who will find this thread in the future. I got the drives working in UnRaid!!! Been quite busy with work and university over the last months so the frustration spread over quite a long period of time. I'll try my best to summarize everything into a couple of bullet points: PREREQUISITS: make sure your HBA or Raid controller is compatible or purchase one that is! here's a very helpful FAQ PDF from Seagate where you can find a table of HBAs & controllers that they have tested and verified to work: https://www.seagate.com/content/dam/seagate/migrated-assets/www-content/solutions/mach-2-multi-actuator-hard-drive/files/sc702.2-2101us-mach-2-faq.pdf make sure everything is on the latest firmware, especially your HBA if it is on the compatibility list. make sure that your controller card is set to the correct mode where it just passes through the drives if you want to run software raid ... like unraid hahahaha i personally purchased a Broadcom LSI 9500-8i NEW ISSUE: you will likely run into another issue where the drive will show up in unraid (or rather, two drives per drive as they get split up into two LUNs), however you can't format or mount them. this is due to it most likely having a 520 byte or other sector size if you bought it used. i don't know how they show up from factory. lukily, this can be fixed STEPS THAT WORKED FOR ME: i downloaded the latest SG3_utilz ".tgz" file (https://sg.danny.cz/sg/sg3_utils.html - gotta scroll aaaalll the way to the bottom) manually copied it (yes, the full zipped folder) to my UnRaid boot usb stick into a folder called "extra" and installed it in unraid via the following command in the terminal: installpkg /path/to/sg3_utils-1.48.tgz of course, make sure to insert YOUR path and YOUR file name to verify the install i wrote "which sg_scan" just to see whether it outputs a file path i then had it list all the drives in my system: sg_scan -i now, find the Mach2 drive that you would like to format (ideally it shows up in the list hahahha) if you want to, you can check the current sector size with sg_readcap -16 /dev/sdX swap out "sdX" for your drive's designation (for me it was sg__ not sd__), however if you get an error message that says sth about the drive not responding properly or not being ready like for me, that's okay you can still proceed, at least that's what i did and it worked format the drive to the correct sector size with sg_format --format --size=512 /dev/sdX again, change sdX to your drive. for the Mach2 drive, choose the first LUN. again, each drive will show up twice, each with half the drive's capacity due to its dual read/write head design. however, what i've found was that it still formats both as afterwards both LUNs showed up as formatted - no idea why tbh lol next, wait ... a looooong time. for my 14TB Mach2 drive it took roughly 24 hours to complete. it takes FOREVER because it's overwriting every single bit with 0s to create the new 512 byte sector size - at least that's how i could explain it after it's done, check the capacity with sg_readcap -16 /dev/sdX NOTES: if you shut down your client machine in the meantime (not the actual server, please don't do that) and the progress counter disappears you can get it back with watch -n 5 sg_requests /dev/sdX again, swap out sdX for your drive HELPFUL SOURCES https://forums.unraid.net/topic/71348-sas-drive-520-sector-size/ https://forums.servethehome.com/index.php?threads/how-to-reformat-hdd-ssd-to-512b-sector-size.4968/ https://www.reddit.com/r/unRAID/comments/rfwfb7/added_new_disks_but_they_show_size_zero/ and ChatGPT ... a loooooooooottt of ChatGPT. I rarely use it but when it comes to code stuff it can be an absolute life saver. I don't think i could've managed to get these drives running without it but i will post this summary of my journey for people who like a different type of guidance I will keep you updated on benchmark numbers once I have the other drive formatted as well and mounted into my array! Thanks again for all the help from you guys! you're awesome

Thanks for the very lengthy reply! Really appreciate all the info I'm gonna try to keep it short 😂 - I updated it controller through the BIOS of my editing PC. Somehow MaxView Storage Manager didn't want to run in OS but it worked through the BIOS. - Our settings are pretty much the same so I suspect it's the controller being too old. I was hoping to somehow get it to work regardless as LUNs are nothing specific to Seagate's Mach2 drives. As you mentioned, there's a FAQ by Seagate that lists tested HBAs and Raid controllers. I saw that one a little while ago but was hoping to get it working on my 8-series controller with the new firmware. Gonna try to get my hands on an Adaptec 1000-series HBA soon. - Regarding my backplane. It's just a "dumb" backplane however it still has a bunch of microcontrollers, pins and jumpers to play around with. I have two Mini-SAS cables breaking out into four SATA / SAS data connectors each that then plug into the backplane. The backplane also distributes power via two molex inputs. The Mini-SAS cables have an additional unlabled 8-pin plug on the SATA connector side that supposidley plugs into the backplane. What is this cable for and does it make a difference? It's unlabled so I'm not sure where to plug it in and the one spot that looked somewhat obvious didn't make a difference. I'm gonna look into the backplane I have a bit more just to learn how they work. Until now there wasn't a need to dive into that topic but it doesn't hurt to learn about it for furute use. Maybe it IS the backplane that is messing with my setup 😂

Okay so a quick update: I managed to update the firmware to 33556. Now we're onto a new issue. The drives don't even show up in the controller BIOS anymore which they did before. For context, I have five other drives connected to it as well. Three of which are SAS, the other two SATA and all of them work without any issues. Unplugging said drives does not yield any difference - the two Mach2 drives still don't show up. When I head into the third option of the menu (can't remember what it's called right now) I get the usual prompt "scanning topology" (or sth similar) and then "scanning for SAS drives ... " which is where it starts counting to 4 (so 5 drives) and then just shows all of the working drives. Question for you - what do your "controller settings" look like? What backplane mode are you running in? I mean, it shouldn't make a difference for being able to just SEE the drives in the controller BIOS but now I'm a little stunned that the drives just *disappeared* so to speak lol

maybe sth else to note is that my motherboard is quite old and only has PCIe2.0. The controller runs on PCIe3.0. However, the other drives on that controller work completely fine. No issues there.

Hi Simon, I can see the drives in the controller BIOS, however I can't format them. It spits out "SAS command error" after a couple minutes. So to answer your question: they aren't. But I can't change anything either. Gonna try to update the firmware, maybe that'll help

Hi Wody, thanks for the update! I finally have some time to look back into this issue. I'm still quite unexperienced when it comes to the deeper levels of software. Again, very much into hardware, but software (especially linux) is sth that I'm in the process of learning atm. So how do I update this controller with FreeDOS? Just flash a USB drive, boot from it ... and then?

Okay sounds like a plan. I'm currently rebuilding parity cause I added a 16TB drive as a parity drive so I won't be able to shut down the server or get ahold of the controller for at least another day but I'll post an update and if it worked when I get back from video shoot on tuesday.

Hi Wody, thanks for the suggestions. The controller definitely recognizes the drives. I can see them in the controller BIOS. I have other drives connected to this controller as well (including SAS drives) that show up in unraid without issues. The firmware aspect is a good point. I was hoping this wouldn't affect it as, at the end of the day, it's basically just two virtual SAS drives per HDD. To your point of adding them to an array - gave that a shot as well. However since the controller can't format them and spits out a "SAS command error", they won't show up as initialized drives in the raid array menu :/

Hello everyone, I'm mildly new to Unraid. Generally speaking, I'm quite good with hardware but struggle with software. I recently got my hands on some Seagate Mach2 drives, the ones that have two read/write heads. I'm expanding my server with a JBOD and got a SAS controller along with the drives. The Mach2 drives I have are the older ones (2X14 version) that only come in SAS and (normally) should just show up as two 7TB LUNs. Normally... In the Controller BIOS I can see them, however, I can't format them. That's not tooo big of an issue as I could just format them in Unraid - if they would show up there... The Controller Backplane mode is set to "RAID: expose RAW". I tried HBA mode as well but without any luck. The Log clearly shows that Unraid acknowledges the existence of said drives however that's where it ends. I've tried some scripts that I saw in a different thread, however the menu that opens just closes every time I press any of the buttons. How the HELL do I get these stupid (but amazing) HDDs to show up?? I'm kinda frustrated and out of hope as I've been battling this issue for the past two days. I attached the diagnostics. Thanks in advance for any help! - Timke thevault-diagnostics-20241016-2125.zip