Linux – How to monitor RAID status when using an external eSATA RAID5 SATA port multiplier

esatalinuxmonitoringraid

I am using an external eSATA device which takes 5 SATA drives and presents them as one large HW RAID5 to linux (ubuntu).

It uses a SiI3726 chipset.

Linux sees and handles the sata device just fine, but I'm wondering if there's any way to query/monitor the RAID5 status that's hiding behind this HW RAID.

(from dmesg — I swear I don't have a 16T single drive…)

[   16.409678] sd 4:0:0:0: [sde] 31255691264 512-byte logical blocks: (16.0 TB/14.5 TiB)
[   16.409727] sd 4:0:0:0: [sde] Write Protect is off
[   16.409730] sd 4:0:0:0: [sde] Mode Sense: 00 3a 00 00
[   16.409752] sd 4:0:0:0: [sde] Write cache: disabled, read cache: enabled, doesn't support DPO or FUA
[   16.463573]  sde: sde1
[   16.463785] sd 4:0:0:0: [sde] Attached SCSI disk

(from lshw)

   *-disk:4
        description: ATA Disk
        product: SATA H/W RAID5
        physical id: 4
        bus info: scsi@4:0.0.0
        logical name: /dev/sde

Any guidance on peering at the system underneath would be appreciated.

RAID status is my big concern, but actual drive models would be helpful too.

I looked at some libatasmart tools, but couldn't find anything regarding SATA port multipliers in general.

There are utilities to check/set the RAID settings in OSX/Windows, so it is apparently possible. I'm looking for a way to do this in Linux and then potentially add to Nagios, etc.

Here's what the HW looks like:
card in chassis

Best Answer

You may be one of the only people who have run into this issue :)

Well, possibly... The use of SATA multipliers is a no-no in server-class systems. Heck, using SATA is a bit risky these days, with ever-increasing drive capacities.

It's not surprising that you've had a difficult time finding information about the SATA port multiplier and monitoring under Linux. Using a SAS expander is the preferred and more supportable approach. Expanders are the norm for server backplanes and external storage JBOD enclosures. As a result, port multipliers are somewhat rare and don't have much mindshare. Adding a layer of abstraction through eSATA almost eliminates any chance of your drives being exposed to the OS, unless the card you're using in the host has OS-lever driver support.

What type of eSATA host card are you using?

At this point, I would rely on the enclosure and visual LED status checks to determine array health. Provide more information about the device, and there's a slim chance status can be communicated to the host (if using the right card), but I wouldn't expect it otherwise.

Edit:

The enclosure being used here does not have LED indicators for drive health. You won't have any way of visually determining drive array status or doing this via your host.

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Edit

I reached out to the manufacturer for support:

The OP post a wrong part that is why no one can help :-) See: https://serverfault.com/a/644247/13325

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