Setting up HARDWARE RAID with QUAD SATA-HAT (jms561 controller)
Hi,
In the case of a fault disk, how I will receive the alert or see the warning?
Hi, led indicators in front of sata-hat case are still useful for several kinds of hdd hardware errors. Also, raid-manager have DC C{N} and SR C{N} command that will return controller and raid states. You can use awk parsing and a bit of bash scripting to get this field from raid-manager in automatic manner. And i think thats all you can use to register raid errors in hardware setup. Of-course, MDAMD is more verbose and more user friendly in this case.
And what about a SATA HAT hardware faluire?
I think I have to buy a new SATA HAT to access my data.
Yep, like with any other hardware raid solution failure.
i will probably weigh in that in order to revive data in the event of hardware failure (ie, piNAS dies), you can only retrieve your data with another JMS561 controller…
the benefits of software raid is compatibility… hardware dies, you can plug the disks into another linux system and retrieve your data…
so if ur using this as a longer term backup option, go with software raid… performance is not critical… if you use it as an active network disk, then hardware raid might be better…
Umm, why would the data be not retrievable? RAID 1 is easy, just connect one of the disks to a normal SATA adapter. With RAID 0 you’d need the striping parameters, then you can tell mdadm to assemble the disk in software.
So the hardware RAID1 just doing similar like a simple EXT4 partition HDD?
Just doing every modification on the both HDD?
Nothing hardware specific related thing?
I haven’t done this before (hardware RAID1).
Somebody should try it out.
Create a hardware RAID1, copy some files to the HDDs, and connect one of the HDD to eg. a PC and check what we can see.
RAID 1 is by definition mirroring identical data to two disks.
Some controllers shift the whole data to the end so they can write their own special header, block sync state and whatnot to it, but a better idea is to do that kind of thing at the end of the disk.
That is really good information!
For my understanding:
To switch from software RAID to Hardware RAID, the software RAID must first be deleted. Then i can create the first RAID0 with CR C0 D0,1 R0 and with CR C1 D1,1 R0 the second RAID0. Is it still possible to create a RAID10 from both RAID0?
You can create RAID1 software from your two RAID0 hardware arrays. This will be close enougth to software RAID10 logic.
Sorry, I ask again:
With raidmgr_static I can only create RAID0 or RAID1?
To get a RAID10, I need to create a software RAID10 with mdadm out of 2 hardware RAID0?
Exactly. Only RAID1, RAID0 and JBOD are supported by this controller.
Hardware RAID and software RAID (mdadm) usually aren’t compatible with each other, you’ll probably need to get a replacement hardware RAID controller of the exact same make/model to reassemble your array.
RAID 1 is still ok because its just mirroring the data, so using it as individual disks is not much of a problem… RAID 0 is going to be a big issue because you cannot retrieve the data using mdadm if u used JMS hardware raid… you will need to buy another raid controller to retrieve the data…
thats why for longer term storage where performance may not be that critical, its best to go for software raid because you can quickly and easily move your disks from system to system and rebuild…
@user12345 thanks for the guide. I tried the same setup, with only two drives and whenever I try to make the ext4 partition for the raid0 dev the command crashes
and dmseg has the following errors:
I power the rpi with a 12v 4pin from a PC psu and only have 2 drives connected.
What is wattage on Your 12V line? Are You connecting ssd or older hdd? 3.5?
Radxa recommends 12V 4A power supply. If there is too less power then disks die on spin up.
Hey @dominik, the psu is a Corsair TX650 and i use the 4pin floppy disk connector on the hat. I don’t use any other supply to power the pri or the hat (should I ?) The drives are 2 (out of 4 i want to use) 3.5 hdds that are powered through the hat.
Also noticed that the raid manager does not find the controller anymore:
Update to my issue and future stupid me.
As it seems I had a leftover sw raid0 and on top of that I was trying to make a hw raid 0, which worked but failed during the partition making. I removed the sw raid and created a hw one and now it works. The new issue is the very slow speeds which I will try to troubleshoot based on the other threads.
You should see both controllers if they are connected and have enough power to operate. I don’t know if that corsair produce needed power on that particular line, but it’s easy to measure with multimeter.
Software RAID relay on higher layer so this should not be the case here. Check out lsusb - You should get two controllers via blue-usb bridge and therefore jmb manager communication. Hardware RAID will cover pysical devices on system.