Disks accessed every few seconds

[Robert Smith]

Hi,

I am configuring my first non-virtual FreeNAS system (FreeNAS-9.2.1.6-RELEASE-x64, Intel i3-4350, 16GB ECC memory).

I created a RaidZ2 volume out of four 4TB SATA disks. Under the volume I created a few ZFS Datasets. I configured and tested email reports. Then I configured and started CIFS and UPS services.

After which I noticed that all four of the disks are being accessed every minute and a half, or so, with a short burst. That happens even when I am not logged in to the interface.

I have yet to configure any shares, NAS users, or place any user files on the NAS. The HDD Standby is “Always On,” and Disk Advanced Power Management is “Disabled.”

I was wondering if this is normal that my disks get accessed all the time. Is there a way to see what is accessing the disks?

Thanks

 

[cyberjock]

Your logs and CIFS data is in the .system dataset. So yes, this is normal.

 

[Robert Smith]

I see. I appreciate your reply.


Please consider this as a request to implement more intelligent log management.

For NAS servers that are infrequently accessed, constant pounding on hard drives is wasteful.



Thank you

 

[danb35]

...and what would you propose as "more intelligent log management"? The system is always doing something, and a lot of that something generates log entries. Those log entries have to go somewhere. Fortunately, FreeNAS lets you choose where they go, so if you don't want regular access to your drives, you could set up a separate pool on, say, a separate USB flash drive, or perhaps an SSD, and put the .system dataset there.

 

[DrKK]

While I understand and appreciate the OP's concern over needless disk accesses, I don't think this kind of activity is an unusual use-case for hard drives, especially NAS hard drives. I think there is probably no effect on the longevity of the drives, nor is the power consumption much to worry about.

That being said, I'd be lying if I said I didn't think it was kind of unnecessary to have it handled this way.

 

[AlainD]

This new log behaviour makes spinning down disks not realistic. Considering that in most households and SMB there are large time windows that there's no activity, this is a pity. Freenas also has no build in "smart" conditional shutdown features.
It's a waste of energy to keep a freenas box on all the time if it's not used for approx. 16 hours.

 

[joeschmuck]

You can move the .system dataset to another drive and this is actually practiced by many users. This would be covered in the User Guide Linked Here. I don't mind keeping it on my hard drives as they are running all the time anyway and it's very little activity. I will eventually place my .system dataset on a SSD along with my jails whenever I start replacing my hard drives with larger ones (in Nov 2015 if they hold out that long).

 

[AlainD]

You can move the .system dataset to another drive and this is actually practiced by many users. This would be covered in the User Guide Linked Here. I don't mind keeping it on my hard drives as they are running all the time anyway and it's very little activity. I will eventually place my .system dataset on a SSD along with my jails whenever I start replacing my hard drives with larger ones (in Nov 2015 if they hold out that long).

Yes I could add 2 SSD's (raid-1) just for this. Rather useful for a big freenas machine, but not for a 6-disk raid-z2 box in a home or SMB context.

If there was a simple automatic shutdown option, this would be not as problematic. (I have WOL up and running.)

 

[danb35]

Why would you feel the need to mirror the .system dataset, if the logs are as unimportant as you seem to think?

 

[AlainD]

Why would you feel the need to mirror the .system dataset, if the logs are as unimportant as you seem to think?

First, there is CIFS data on the .system partition
Second, I don't say that logs are unimportant. Logging while a machine is idling, is probably far less important.
Third, I suspect that if the .system partiotion is gone, the system would need manual intervention and "work".
Fourth, if 1 SSD is added, the second SSD isn't that much work.

 

[9C1 Newbee]

You think logging is bad, just wait till you start a scrub. You are gonna lose your mind.

 

[cyberjock]

Third, I suspect that if the .system partiotion is gone, the system would need manual intervention and "work".

Uh, if the .system partition disappears it means your pool didn't mount. You won't give a crap about the .system partition because you'll be in "sh*t my pants" mode at that point.

 

[joeschmuck]

Yes I could add 2 SSD's (raid-1) just for this. Rather useful for a big freenas machine, but not for a 6-disk raid-z2 box in a home or SMB context.

If there was a simple automatic shutdown option, this would be not as problematic. (I have WOL up and running.)

I gave you the best free advice I could given your request, and I doubt a $40 SSD is going to break the bank. You don't need a large SSD, any 32GB SSD or larger will do fine for the .system dataset and a lot of jail action. You just need to wait for one to go on sale. And you don't need to mirror them, it's just advised if you run jails from the same SSD.

As for automatic shutdown... You sure can do that and set FreeNAS to shutdown at a certain time everyday if you like.

 

[AlainD]

I gave you the best free advice I could given your request, and I doubt a $40 SSD is going to break the bank. You don't need a large SSD, any 32GB SSD or larger will do fine for the .system dataset and a lot of jail action. You just need to wait for one to go on sale. And you don't need to mirror them, it's just advised if you run jails from the same SSD.

As for automatic shutdown... You sure can do that and set FreeNAS to shutdown at a certain time everyday if you like.

Hi I have a small (120GB) SSD lying around, that's not the problem. Adding 2 sata ports to a freenas box is a little bit more trickier. If I do this I would also place some usefull data on it, the accesstime for a SSD is far lower.

However it's not that usefull to add a SSD to a low usage (in time) freenas server. This probably because there a bit aggresive logging while idling.