Disk failing

P

Pete999999

New Member
I've noticed jittery playback and diags reports the disk is failing - see attached.
I'm advised to go to disk diags which tells me there's a problem, but not how to fix it.
Any suggestions much appreciated
Thanks
Pete
humax1.JPG
 
These are symptoms of the hard drive being close to failure, and requiring replacing. Replacement is simple for somebody who knows one end of a screwdriver from the other, it is less simple to choose a new HDD. The WD (Western Digital) Purple range seem to be OK from reports (IIRC - I'm sure somebody will correct me if not), you need a 3.5" SATA drive, up to 2TB in capacity.

Meanwhile, you may be able to extend the existing drive's life temporarily by sorting out the file system. See Quick Guide to Disk Recovery (click)
 
Hi Black Hole and thanks for your reply.
I see Amazon have the 2TB WD purple disks for £66 - I'll leave it a while just to ensure no one says not to use the WD Purple, then order it this evening.
I'm not too bothered loosing all the stuff on the old disk - most of it has been there for years and never watched..
I'll post back in a few days to say how well it all went (hopefully)
Thanks again
Pete
 
Pete999999 said:
I'm not too bothered loosing all the stuff on the old disk - most of it has been there for years and never watched.
Click to expand...
That's a refreshing attitude. Most have top save it. It's only TV afterall. Repeats will be along in a minuite.:)
 
If you can get one, go for an AV drive.

The Red and Purple drives are designed for RAID use and so have TLER (an error recovery option) enabled which can cause problems if there are problems with reading or writing to a sector. AV drives usually have this parameter disabled so that a failed write is just ignored and recording moves on. It can also cause problems with dealing with any problem sectors in the future as it causes some problems to be hidden from the host (the Humax in this scenario). A quick web search shows up a fair number of warnings that say using a TLER/ERC-enabled drive without a RAID controller is advised against. Bear in mind that this doesn't really matter if the drive is completely healthy.

I would actually recommend avoiding the WD Purple drives. They have a surprisingly low workload rating (around 60TB/year) which I suppose is a consequence of their intended use in large surveillance arrays.

From the spec sheet:

1 million hours MTBF
Best-in-class reliability for mainstream
3.5-inch form-factor surveillance
storage.*

* Based on a surveillance usage of <60 TB/year transferred at 25°C
ambient environment with up to 16 cameras
Click to expand...

That's one hell of a footnote, in light grey too!

They also have a load of other specialised features in their firmware which may cause problems that we can't predict. If going for a WD disk which isn't an AV model, choose a Red. It still has TLER enabled but otherwise it's a good fit and has three times the workload rating.

With any non-AV WD disk, watch the disk stats to check if the load/unload count grows quickly and if so look for the wdidle3 utility to disable the head parking, which will involve connecting the drive to a SATA bus on a different computer somewhere. I think that's unlikely to be happening on a surveillance disk but you never know - it /is/ usually set to 8 seconds from the factory on the reds though.
 
Thank you all for your advice.
Glad I didn't jump in and get the WD.
I don't know of any particular AV disks but note the recommendation of a
Seagate ST2000VM003 - Pipeline HD (2TB) 3.5 inch Hard Drive (5900rpm) 6Gb/s SATA 64MB (Internal)
That Black Hole posted a link to.
Any reason not to go for that one?
Cheers
Pete
 
af123 said:
With any non-AV WD disk, watch the disk stats to check if the load/unload count grows quickly and if so look for the wdidle3 utility to disable the head parking, which will involve connecting the drive to a SATA bus on a different computer somewhere. I think that's unlikely to be happening on a surveillance disk but you never know - it /is/ usually set to 8 seconds from the factory on the reds though.
Click to expand...

WD has released a utility specifically for their Red drives. Personally, I would only start thinking about using the utility IF there is a significant problem.

http://support.wdc.com/product/download.asp?groupid=619&sid=201&lang=en
 
That's interesting! I contacted WD prior to ask them what drive they recommended for a PVR (as there is no longer a AV specific model) and they suggested the WD Purple. I decided to switch back to WD after different 3 Seagates failed on me recently. The Purple in my Hummy has been trouble free thus far, fingers crossed it stays that way :eek:
 
The current disk is a Seagate Pipline 1 TB - Seagate also sell a 2TB Pipeline disk - wouldn't it make sense to go for that?
 
As 'smartmontools' is installed as part of the CFW you should be able to check the status of your drive from the command line in Telnet (assumes your drive is mounted as 'sda'):
Code: 
smartctl -l scterc /dev/sda
The following should disable TSER if enabled:
Code: 
smartctl -l scterc,0,0 /dev/sda
I've not used the command to change the setting myself, so use at your own risk. There is an overview here.

EDIT. Reading around a bit more, not all drives support this function (seterc). I presume if the first command successfully lists the status, you should be able to change it using the second.
 
Last edited:
MontysEvilTwin said:
EDIT. Reading around a bit more, not all drives support this function (seterc). I presume if the first command successfully lists the status, you should be able to change it using the second.
Click to expand...
I read on the Tivo forums that WD disabled the ability to change this on later drive models but if it does work then it could easily be done at each boot.
 
sceptic said:
That's interesting! I contacted WD prior to ask them what drive they recommended for a PVR (as there is no longer a AV specific model) and they suggested the WD Purple.
Click to expand...

What about the ones at http://www.wdc.com/en/products/internal/av/ ?
The 2TB model seems readily available - for example at http://www.scan.co.uk/products/2tb-...am-sata-iii-6gb-s-intellipower-rpm-64mb-cache
or http://www.ebuyer.com/524859-2tb-wd-av-gp-video-and-surveillance-hard-drive-wd20eurx
 
MontysEvilTwin said:
As 'smartmontools' is installed as part of the CFW you should be able to check the status of your drive from the command line in Telnet (assumes your drive is mounted as 'sda'):
Code: 
smartctl -l scterc /dev/sda
The following should disable TSER if enabled:
Code: 
smartctl -l scterc,0,0 /dev/sda
I've not used the command to change the setting myself, so use at your own risk. There is an overview here.

EDIT. Reading around a bit more, not all drives support this function (seterc). I presume if the first command successfully lists the status, you should be able to change it using the second.
Click to expand...

That's very interesting, I hadn't realised that smartmontools could do that.

As I mentioned, I recently bought a WD Red 3TB for use in my HP Microserver (Ubuntu Server), but not in a RAID configuration**. I read a lot about Reds vs Greens for "stand-alone" drives (i.e. drives not in a RAID configuration) but some of the comments/advice might not be the most well informed (as always) - so I'm not at all sure I made the right decision (vs WD Green). Anyway, I tested "sudo smartctl -l scterc /dev/sda" on the Red and, as expected, it gave Read and Write as both 7 seconds. I *might* pluck up courage to see what happens if I try to set it to more suitable values for a standalone drive (then again I might not!).

Incidentally, the Red so far has had 10 Load/Unload Cycles in 97 Power On Hours, so it looks as though the head parking isn't a problem with it, at the moment anyway. This is much less than the 2TB WD Greens I have, which average around 9 Load/Unloads per hour with the Ubuntu Server OS.

** I have a second HP Microserver box, in a different part of the house, which I daily mirror my main box to.

Apologies for going off on a diversion.
 
Last edited:
Hmm, so the day after I browse to ebuyer looking at their hard disks, I get an email entitled "Hard Drive Offers" with the WD Red 2TB reduced to £69.99.. coincidence?
 
johnb said:
Anyway, I tested "sudo smartctl -l scterc /dev/sda" on the Red and, as expected, it gave Read and Write as both 7 seconds. I *might* pluck up courage to see what happens if I try to set it to more suitable values for a standalone drive (then again I might not!).
Click to expand...

For information - I did test using sudo smartctl -l scterc,0,0 /dev/sda on a WD Red 3TB drive. It worked fine but the new setting setting didn't survive a power down/power up, so if someone really wanted to use this the command would have to be set to run every start up.
 
You must log in or register to reply here.
Back
Top