How to Isolate Problem with External RAID0

[koberulz]

My video captures are dropping frames, a problem I've isolated to my external USB3 RAID0 array as I can capture just fine to my C:\ drive (which is obviously only feasible as a troubleshooting method).

I have no idea whether it's one of the two 2TB 3.5" drives, or both of them, or the enclosure, or all three, and I'd like to avoid replacing any gear that doesn't need replacing as I've already bought a new laptop thinking that was the issue.

Is there any way I can isolate the problem? I do have important data on the array.

[jagabo]

Use an internal drive for capture. Copy to the RAID drive when you're done.

[lingyi]

If you haven't done so already, backup everything on your RAID array immediately before doing anymore troubleshooting.

[koberulz]

I have the RAID because the internal drive isn't up to capturing.

It was working previously, so it can be done. This may or may not be related to me dropping the RAID some months back, although it did work afterward (after I replaced one of the drives).

[jagabo]

Make sure you are connected to a USB3 port. Your laptop may have a mux of USB2 and USB3 ports. Check the device's write speed. Make sure you get over 30 MB/s sustained (more like 60 to 200 MB/s). Remove the drives from the device and check them individually.

In my opinion it's a mistake to use RAID0 for capture. It just adds another layer of complexity. If you can't capture to your internal drive use a single USB3 external 3.5" drive with its own power supply. RAID0 is not an effective backup solution. It's an uptime solution.

[JVRaines]

First, back up your important data. Then apply standard isolation technique: switch out one item at a time until you find the bad component. Items include each drive, the enclosure, your USB cable, USB port, and USB hub controller.

[koberulz]

Make sure you are connected to a USB3 port. Your laptop may have a mux of USB2 and USB3 ports. Check the device's write speed. Make sure you get over 30 MB/s sustained (more like 60 to 200 MB/s). Remove the drives from the device and check them individually.

I've only got USB3 and USBC. When I tested on the old laptop I was getting around 180MB/s, I think? Haven't tested the new laptop but not sure if this issue will affect results (or if I have the speed test software installed...the BlackMagic setup SD card died on me). I'll look into it though.

Check them how? Just throw them in an enclosure and do a speed test? I assume I can't do that without losing the data that's on them?

In my opinion it's a mistake to use RAID0 for capture. It just adds another layer of complexity. If you can't capture to your internal drive use a single USB3 external 3.5" drive with its own power supply. RAID0 is not an effective backup solution. It's an uptime solution.

It's a speed thing. It's literally only for capture, ideally, I've just filled my storage drives up and there's a bit of a holdup getting new ones. It's not meant to be for backup or whatever, just an uptick in write speed over a standard one-drive setup.

First, back up your important data. Then apply standard isolation technique: switch out one item at a time until you find the bad component. Items include each drive, the enclosure, your USB cable, USB port, and USB hub controller.

I'm not sure what a "USB hub controller" is. The problem has occurred on two different laptops though.

As for switching items out, if I have to buy a new enclosure and two new drives why bother testing? I'm hoping for something that can narrow down what needs replacing.

EDIT: Ugh, just booted up and the drive shows, but no information about what's on it and I can't access it. Delightful.

[jagabo]

Check them how? Just throw them in an enclosure and do a speed test?

Check SMART reports (the vendor of the RAID box may give you utilities to do this), surface scans, speed tests...

I assume I can't do that without losing the data that's on them?

Depends on the tests you run, file system, etc.

Ugh, just booted up and the drive shows, but no information about what's on it and I can't access it. Delightful.

I guess the data loss issue when testing is no longer of concern.

In my opinion it's a mistake to use RAID0 for capture. It just adds another layer of complexity. If you can't capture to your internal drive use a single USB3 external 3.5" drive with its own power supply. RAID0 is not an effective backup solution. It's an uptime solution.

It's a speed thing.

Sorry. The backup comment was because I was thinking of RAID1 (mirroring). Are you capturing SD or HD? Compressed or not? Any single modern drive should be good enough for SD capture with a lossless codec. HD requires more bandwidth with uncompressed or lossless compresssion. HD with lossy compression can usually be done with a single drive.

Also keep in mind that hard drive speed varies depending on whether you're reading/writing the inner cylinders (slowest) or outer cylinders (fastest). A full drive is generally slower as drives tend to fill from the outside edge (unlike DVD/CD which fills from the inside).

[koberulz]

I tried rebooting to see if I could get the RAID to at least be readable again. Pressed 'restart' before coming in and posting on here.

It's still rebooting. Almost four hours later.

I'm capturing in both HD and SD.

[koberulz]

After rebooting, attempting to access it throws a "drive is corrupted and unreadable" error.

Fantastic.

[koberulz]

Pulled the drives out and put them in an enclosure. Neither show up under "This PC". One shows up in Disk Management but I can't figure out how to format it or initialise it or whatever I need to do. The other doesn't even show under Disk Management.

I did previously have to replace one of the drives, but I can't remember which it was. Would there be a potential concern with a specific drive slot in the enclosure constantly causing that drive to fail?

EDIT: Okay, after posting the above it's finally shown up, as "Unallocated", and it'll let me initialise it. The first disk I tried showed up as "GPT" or something similar, from memory, and had a different right-click menu with no "Initialise" or "Format" options.

[Cornucopia]

Sorry to be blunt, but if you do not even know what those terms are or how they do or do not relate to your issues, you shouldn't be dealing with RAID at all to begin with.
If you need faster disc speeds, try an SSD. Then use those leftover HDDs as longer term/archival storage.

Scott

[koberulz]

Very helpful.

[lingyi]

It's unclear from your posts exactly what you're trying to do, but it sounds like you've given up on recovering the data on the drives (which is unlikely to succeed anyway) and just trying to test your drives. If so, see if you can mount and format the drives with Linux (you boot from a live distro like Ubuntu on a flash drive). Once the drives are formatted and recognized in Windows, run Crystaldiskinfo and if anything is yellow or red, the drive is failing and needs to be replaced.

As for hardware troubleshooting, your USB port and controller are working (since one drive is recognized), but yes, a bad interface on your RAID box can corrupt your drives. That's one of the dangers of RAID 0, if anything happens to one drive, the entire array fails and the data is likely gone.

[lingyi]

Use an internal drive for capture. Copy to the RAID drive when you're done.

Based on the OP's previous posts, he's probably using a laptop and limited to a single drive.

[Nelson37]

You state that you have two laptops, and that the external drive DID work, though no specifics as to which laptop.

Kudos for actually mentioning that you dropped it, and broke at least one drive. Most folks neglect to mention such critical information.

Now, clarify if it EVER failed BEFORE you dropped it, and also if it EVER worked AFTER you dropped it, and that will likely answer your question.

External RAID0 USB enclosure is just not, at ALL, something I would ever recommend or use. Finicky, flaky, prone to unrecoverable failure.