Syslog stops drive standby

[OJ2k]

I was trying to figure out why my drives were not spinning down.

The 'Reporting' graphs indicated a tiny bit of disk activity every 5 minutes, so I started systematically switching off services until it stopped and the drives could spin down. In the end I found that it's the 'syslog' setting (checkbox at Settings -> SystemDataset -> Syslog). There is a 'System dataset pool' dropdown box which only lists my single volume.

Feel like I'm missing something. Presumably syslog is something I should leave switched on (?), but then my drives will never spin down. Any advice?

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Update:
FreeNas version 9.2.1.7

 

[danb35]

Yes, this is working as designed. If it's important to you that your disks spin down, you'll need to set up a separate pool, perhaps on an SSD, for your .system dataset.

 

[OJ2k]

Ahh, I hadn't planned for that. Wonder if I can use a small USB memory stick. If not then I'll get an SSD and also put jails and common plex media on it.

 

[cyberjock]

You can, but don't expect the USB stick to last long.

SSD is the better option. Of course, it's not recommended you spin down disks anyway. They seem to last far longer when you never spin them down. But to each their own.

 

[pschatz100]

Ahh, I hadn't planned for that. Wonder if I can use a small USB memory stick. If not then I'll get an SSD and also put jails and common plex media on it.

When I first configured my system, I put all my jails on a small USB memory stick precisely so I could spin down my drives. I have since reconfigured my system and eliminated the second memory stick (I still boot from a memory stick.) Here is why:

I no longer spin down my drives. There are lots of posts in the forum that discuss this issue, so I won't go into that here. However, once I decided to stop spinning down my drives, the main reason for putting jails on a USB memory stick went away.

The latest versions of FreeNAS use Samba4, which requires constant access to a .syslog directory. This creates lots of "reads and writes", and memory sticks are notorious for write problems. I had used a well known memory stick and it began to show problems after a few months. For this reason, I would never put the the .syslog directory on a memory stick - so this means keeping at least one disk running all the time, or using an SSD.

You mentioned Plex. The Plex database is where Plex keeps all its meta data about your media (not the media, itself.) Furthermore, the default plugin update process as run from the FreeNAS GUI creates a backup copy of everything, including the database. So, if you do decide to use a USB memory stick, plan on buying one that is at least 4 times as large as you expect your Plex database to grow into. In my case, the Plex database is about 3Gb, so if you decide to use a memory stick I would not recommend anything less than 16Gb.

 

[OJ2k]

Appreciate the balanced explanations. Am going to avoid the USB sticks. I still have a mental barrier to overcome on the environmental/power consumption front, but I'm getting there:

• Measurements indicate I save 13 watts by spinning down my embarrassingly small 3-way mirror. Maybe I'll move to a simple 2-way mirror and keep a drive on the shelf.
  
• Power saved should probably be offset against the cost of buying new drives sooner - but there's no way I can do that calculation.
  
• The drives seem very reluctant to spin down when using CIFS (instead of AFP). I don't know if it's an issue with OS X or the samba 4 syslog thing that pschatz100 mentions.

Perhaps I'll give in

 

[cyberjock]

If you saved 13w of power 24 hours a day for 5 years at 10c/kWh (which is ungodly cheap for most of the USA as well as the world), you'd save.... $55 total. Yes, it's $11.39 cents saved per year. But I promise you the wear and tear will cause you to RMA at least one drive as a result, so those "savings" are instantly replaced with 'shipping and handling' as well as "inconvenience". See why I tell people that spinning down your disks isn't worth it. A single disk just doesn't save as much as people thing, and people somehow think that savings made with 10+ disk spinning down is better. It's not. This is per-disk and 10 disks only means 10x the savings and 10x more drives that might need RMAed.

 

[pschatz100]

Add to cyberjock's comment:
The environmental impact of manufacturing a drive is greater than the savings associated with spinning it down. If you have to replace drives more often, then you are negating the value of spinning them down.