PDA

View Full Version : Best and largest 2.5 inch HDD for 24/7 operation



JerryK132
08-05-23, 17:33
The last drive I attached (via USB i/f) to my stb died after a few months and I learned that not all drives cope very well with 24/7 operation! I gather that "surveillance" drives are the best in this respect and also that SMR recording might be a desirable feature - along with low-current operation generally. Unfortunately there is not much available in the 2.5 inch form factor needed for my VU+Duo4K-SE internal carriage.

The ST5000LM000 Seagate BarraCuda drive family seems to comply although the spec does not give MTBF figures nor is it explicitly surveillance rated. So my question is should I go for this drive or get a smaller drive like the WD AV-25 drives which are smaller and are made for the purpose. It would seem pointless to go for a larger drive if it will be likely to fail in a year or so!

Since my original drive failed I have been using a Synology NAS drive, but this has proved unreliable giving the occasional Drive R/O Disk Full messages from which the system (Vix?) recovers poorly leaving only 1 minute recorded but continuing to indicate recording unless I explicitly delete the timer. I also have lots of problems trying to record or use Timeshift. As I am using WiFi for the NAS I suspect the timeouts are just too short, so it's back to HDDs. Moreover the NAS seems to be accessed by the VU+ unit almost 24/7 even on standby... Does this apply to hdds I wonder? Wasteful if so...

Sorry about the lengthy question, but having spent hours searching the net and this Forum finding very little regarding hdd choices and related problems, I thought I would provide a bigger picture which might spark some useful responses. TIA...

birdman
08-05-23, 19:07
Moreover the NAS seems to be accessed by the VU+ unit almost 24/7 even on standby... Does this apply to hdds I wonder? Wasteful if so...That will be because you have Timeshift on (I think).

Joe_90
08-05-23, 19:08
- or logging set to the HDD (instead of internal flash).

JerryK132
08-05-23, 19:13
Thanks Birdman. I do, as I want to be able to record TS and rewind live. Is that not the purpose of the TS setting?
If no devices are using the stb (eg via Kodi) and it's in standby, should the drive not go to sleep?

cactikid
08-05-23, 21:04
I would ask if the hdd with usb is also powered externally or not.

JerryK132
08-05-23, 22:25
No it wasn't.
It was a 2.5" portable backup unit.

birdman
08-05-23, 22:37
Thanks Birdman. I do, as I want to be able to record TS and rewind live. Is that not the purpose of the TS setting?
If no devices are using the stb (eg via Kodi) and it's in standby, should the drive not go to sleep?Don't use TS, but my understanding is that if you wake it up and are "interested" in what is on, you might wish to rewind it - so it has to have been recording it. Which means it has to write to storage.

JerryK132
08-05-23, 22:59
I was under the impression that TS recording only started when a service was being watched via the vu+ or remote Kodis. I suppose that implies several simultaneous TS recordings? Is there an automated purge of the TS files? I seem to have many of these on NAS in the Timeshift folder.

Looks like the debug logs are directed to the flash memory in home/root/logs/ after all. But I've switched the debugging off now.

adm
09-05-23, 10:59
Don't use TS, but my understanding is that if you wake it up and are "interested" in what is on, you might wish to rewind it - so it has to have been recording it. Which means it has to write to storage.

My understanding (which may be flawed) is if you want to be able to rewind live at any abitary point then the timeshift setting must be to have the disk continually spinning. The other mode is having the disk go to sleep and timeshift only starts, and the disk wakes up, when you press pause. In this latter mode you can only go forward and then back again to where pause was pressed. In the former mode the background timeshift recording starts 5/10 seconds (configurable) after you change channels.

Joe_90
09-05-23, 11:23
That's right @adm - if you have "Permanent Timshift" PTS set, then the disk is continually in use (after the initial 5/10 second delay) whenever a channel is tuned. Only when you go into standby does disk activity cease. If you don't have PTS set, then timeshift will start if you press play/pause to allow you to stop the programme while making a cup of tea, etc. In that instance you can move forwards or backward in the timeline to when you press play/pause.

JerryK132
09-05-23, 18:44
Thanks both. I'm on Image 6.3.007
I'm a bit confused here. I think that even in standby, my NAS is being accessed. That was the main suspicion. So I'm quite happy if it's being accessed for TS whenever I'm using a service, in case I want to rewind a bit.

However... It seems to me to make sense to save timeshift in flash (2.8GB free) and keep PTS on. That way hdd would only be running when recording. Would this harm flash which is presumably some kind of SSD? Presumably temporary/spent TS files are purged?

Also where is PTS setting - I can't seem to locate it?

JerryK132
09-05-23, 20:55
deleted.....

adm
09-05-23, 22:02
However... It seems to me to make sense to save timeshift in flash (2.8GB free) and keep PTS on.

Very unwise, 1 hour of a HD broadcast is around 2GB and timeshift can be much more than 1 hour if you don't change channels. You are very likely to run out of flash and have problems.



Would this harm flash which is presumably some kind of SSD? Presumably temporary/spent TS files are purged?


Flash is not SSD. It's non-volitile memory - Electrically Erasable Read Only Memory (EEPROM).




Also where is PTS setting - I can't seem to locate it?

Recording and timeshift. It's more to do with having the disk running all the time and how soon the TS kicks in after you change channels. There is no setting limiting the TS buffer space.

JerryK132
11-05-23, 15:19
Thanks adm, that's very helpful. I was getting my TBs and GBs muddled in my mind (I grew up with 4K RAM boards in the late '70s!).

So I've installed my new hdd and set TS to live there whilst leaving everything else (movie, backup, etc) on the nas. Apart from a bit of a waste of 5TB, is that an optimal solution or should I move everything to the hdd? The key point of my nas (apart from sharing) was to avoid what happens when the hdd fails, which is what started me on this adventure when I lost the whole drive, backups, recordings, etc!

I found the "PTS" setting in Recording and Timeshift - there is a (TS) disable setting alongside the "how soon..." setting which I hadn't spotted. Tks for that.