Nearline SAS on SATA controllers

I know that SAS drives cannot operate on a SATA controller.
I know that SATA drives can operate on a SAS controller.

But can Near-Line SAS drives, being SATA drives with a SAS controller, be used on
A) only SAS controllers
B) both SATA and SAS controllers
?

Note that the nearline SAS drives feature "dual port", but I'm unsure if this means "has a SATA and a SAS port" or "has 2 SAS ports". Especially since I seem to read that the connnectors and cables themselves seem to be interchangeable, which, if they are, would make the dual port conundrum moot.

Answer

"I know that SATA drives can operate on a SAS controller" - you may know many popular SAS controllers than can run SATA disks but don't make this assumption, there's nothing in the SAS specs that state they should also run SATA disks, they just share a lot of common features (connectors/cabling etc.). Manufacturers can pick and choose to do as they wish.

Now your question - no this won't work, it's the SAS signalling that's different, so no SATA-only controllers won't be able to work with any SAS disks at all. Also again it's an assumption of yours that all near-line drives are SATA with a SAS controller - that's not the case, it's the controller that defines the protocol used. Near-line SAS disks are just disks, there's nothing inherently SATA-oriented about them, they then have a SAS controller attached to them.

Dual-porting is a SAS feature that allows a single disk to have two physical SAS links out of its controller, this is usually used to allow for diverse electrical paths but can be used to connect a single disk to two controllers to better handle hardware failure. It's got nothing to do with SATA at all.

Comments

linux - iDRAC6 Virtual Media native library cannot be loaded

When attempting to mount Virtual Media on a iDRAC6 IP KVM session I get the following error: I'm using Ubuntu 9.04 and: $ javaws -version Java(TM) Web Start 1.6.0_16 $ uname -a Linux aud22419-linux 2.6.28-15-generic #51-Ubuntu SMP Mon Aug 31 13:39:06 UTC 2009 x86_64 GNU/Linux $ firefox -version Mozilla Firefox 3.0.14, Copyright (c) 1998 - 2009 mozilla.org On Windows + IE it (unsurprisingly) works. I've just gotten off the phone with the Dell tech support and I was told it is known to work on Linux + Firefox, albeit Ubuntu is not supported (by Dell, that is). Has anyone out there managed to mount virtual media in the same scenario?

ubuntu - Monitoring CPU, Mem, disk, on a single server

I've been looking for a simple starter solution for monitoring my [currently] single server hosted solution. Other than Nagios and similar, are there other good (simple) solutions people are using? Answer Everything depends on what you want. For example Munin is very simple, you can install and configure it in less then 10 minutes (on one server), it can sends alarms, make graphs from monitoring cpu, mem. apache connections, eaccellerator, disk io and many many more (it has many plugins). But if you are planning in future get some more machines, munin may not be enough. For example in munin you cant monitor state of individual processes, can't monitor changes in files (for security purpose). So if you wanna only see what is the utilization of basics parameters on your server and don't plan to buy some more servers Munin is what you are looking for, but if you wanna be alarmed when some of your service is down, take more control on what is happeninig on...

hp proliant - Smart Array P822 with HBA Mode?

We get an HP DL360 G8 with an Smart Array P822 controller. On that controller will come a HP StorageWorks D2700 . Does anybody know, that it is possible to run the Smart Array P822 in HBA mode? I found only information about the P410i, who can run HBA. If this is not supported, what you think about the LSI 9207-8e controller? Will this fit good in that setup? The Hardware we get is used but all original from HP. The StorageWorks has 25 x 900 GB SAS 10K disks. Because the disks are not new I would like to use only 22 for raid6, and the rest for spare (I need to see if the disk count is optimal or not for zfs). It would be nice if I'm not stick to SAS in future. As OS I would like to install debian stretch with zfs 0.71 as file system and software raid. I have see that hp has an page for debian to. I would like to use hba mode because it is recommend, that zfs know at most as possible about the disk, and I'm independent from the raid controller. For us zfs have many benefits, ...

Blog

Search This Blog