This is the continuing story of me trying to watch some movies…
So here’s my setup: I have two RAID machines.
The old one has two fanless 4x disk cabinets. It was perfect — I’ve used it for half a decade, but the RAID card died, and the BIOS on the new card doesn’t allow me to spin down the disks, which started this journey.
The new RAID machine is more traditional — it has fans and stuff, but doesn’t make that much noise. Especially since I’m going to place it in the home office, so I don’t have to listen to it.
The new one is a mirror of the old one. I’m using the RAID to store movies I rip from Blurays/DVDs I buy, and I watch the movies from there.
Given that more than 95% of the time I’m not watching movies, I really prefer to spin down the disks and let them rest. Presumably they’ll last longer that way. (Indeed, the ones in the old RAID setup have survived more than half a decade without a hitch.)
So I can play movies from either of these machines, and the other one can be semi-permanently off (unless I’m running a backup). Get the setup?
OK.
But which one to use for watching movies? And how to spin things down?
Well, on the old machine, there’s only one option now: Suspend the entire machine, and use Wake-on-LAN. (Side note — I love the Archlinux wiki — it has such detailed information on all Linuxey things I’m wondering about. And I don’t even use Arch.)
The old machine has an LSI card, and it’s so enterprisey that it takes five minutes to boot. Which makes experimenting with the machine a bit tiresome.
Especially since I had to get into the BIOS several times to experiment with things, but it turns out that if you set “PCIE Devices Power On” to “Enabled”, then Wake-on-LAN works.
That is, if I send a Wake-on-LAN package to it, it switches the screen on immediately and answers ping. But it takes about two and a half minutes for userland to wake up, and the machine to be usable.
Do I want to wait two and a half minutes before watching a movie? Hm.
OK, let’s look at the new RAID machine. On that one, I could theoretically just spin the disks down, and then accessing via NFS would wake them up, and I wouldn’t have to do any explicit waking.
But the machine has fans, and that’s not optimal.
And the fans can’t be spun down manually.
So let’s try to suspend (S3) the machine… and that works fine. Except for this:
The fans keep going. And waking up from suspend takes 30 seconds before userland is available. (It seems to spend this time spinning up the disks.)
30 seconds isn’t bad, but the fans…?
And there doesn’t seem to be anything in the BIOS of this X13SCL-IF motherboard to control the fans, as far as I can tell.
So what about hibernate? If I hibernate instead of suspending the machine, then the fans stop after a couple minutes. But it uses 2 minutes to wake up from hibernation, because it basically has to do a full boot (and Supermicro motherboard are really, really slow to boot).
*sigh*
To sum up:
- Old RAID suspend: 150 seconds.
- New RAID suspend: 30 seconds, but fans run continuously.
- New RAID hibernate: 120 seconds.
There really doesn’t seem to be any perfect solution here. Well, I had the perfect solution, but that stopped working and there seems to be no way to get that back.
Hardware sure is frustrating.
But considering I did have the perfect solution (i.e., disks spin down automatically, and I don’t have to futz with wake-on-LAN, and there’s no fans), can I recreate that with a new RAID/SATA card, perhaps?
A modern SAS card (for eight disks) uses Mini SAS SFF-8644 connectors. My disk cabinets don’t:
That connector is an SFF-8470, which is also called Infiniband/SAS. There are SFF-8644 to SFF-8470 cables, but this is the only one I could find:
And it’s no longer being produced.
Amazon lists the same cable — must be from the same producer going by the image — and says “usually ships within 6 to 7 months”. So I don’t think this actually exists (any more).
So… could I just swap out the backplate on the RAID cabinet to a SFF-8644 backplate? (Are those things called “backplates”?) Like…
But how would I mount this? Use a Dremel on the thing to get it to fit? Hm.
As far as I can tell, these various Mini SAS connectors are all electrically compatible — it’s just a form factor issue? (I’m not at all sure, though.)
The cable I have today looks like this:
Does an adapter from Mini SAS SFF-8088 (that’s the one on the right) to SFF-8644 exist?
Yes!!
But… I’d need two of those since there are two cables, and there’s only room for one of those?
OK, they don’t actually need to be installed anywhere, I guess, but just letting them bop around would be kinda sloppy…. er…
Oh oh oh! I’m thinking extra super stupidly here. I don’t need an external Mini SATA card if I’m going to use the SFF-8088 cable anyway — I need an internal Mini SATA card (which I already bought while testing stuff out on the new RAID machine) and then a converter. Does that exist?
So I just need two of those and everything should, like, work! And there’s room for that in the old machine.
And this is cheap, too — these two gadgets are the only things I have to buy to test this out.
*orders gadgets*
So now I just have to wait for Genuine Modules to deliver… *drums fingers*
Oh, I should have gotten this instead — but I guess it doesn’t really matter.
[To be continued.]