Second USB stick for system dataset(.system)?

[mblund]

Hi,

Is it a good idea to use a second usb stick instead of my zfs pool for the system dataset(.system) ?

I'm about to set up a new freenas server for home use and are now trying out different setups. The server will be used at home with a couple of user with a possible long time between usage. Today the asrock c2750D4 with 16 gb ecc mem boots fine from my main usb stick and use my three wd red disk in a zfs1 pool to hold the system disk/partition. In long time periods of no usages I would like to put the hard drives to standby but I'm concerned about head park issues.

- Do I need to worry about this?

- Could I use a second usb stick for the system dataset instead?

- What would be the downside?

- Could I backup the data on the .system from the USB disk into the zfs disk pool once a day and only risk one days of data from the .system. What would I lose? If it just system settings and logs that are written to the system disk, I would risk last days data from them to be able put the hard drive to standby.

- How many writes are there to the .system partition? Would the usb stick wear out fast in a low usage home system with few users.

- Would it be better to go for a cheap SSD instead of the second usb stick?

 

[joeschmuck]

I see no reason for a USB flash drive to not support the system dataset, the only issue you might have is boot priority on the USB ports so you would have to figure that out but that isn't difficult. I wouldn't worry about wearing out a USB flash drive, they have a good life and are cheap. I'm willing to bet that you change your FreeNAS hard drives before you wear out a flash drive.

If you do give it a shot, make sure you have a backup of all your data. Although I highly doubt damage would occur to your data, I don't know your skill level so you might screw something up all on your own. Most of us old timers here had to do our own testing to see what works and what doesn't so if you venture down this path, give us an update on what works well and what doesn't. Keep in mind that you should post which version(s) of FreeNAS you are using and your system specs.

 

[cyberjock]

Someone did this. It was a disaster. .system is written to every 10 seconds or so, so it's a bad choice. It also causes pauses in the system randomly when it writes data.

There's nothing to gain really, but alot to lose.

 

[joeschmuck]

Ouch! That wouldn't be a good thing. Although I'm surprised I guess that it would cause much of an issue if it's only writing every 10 seconds or so.

 

[cyberjock]

Yeah.. while its not something I'd recommend(writing to flash regularly) I was surprised at the problems.

 

[mblund]

ok thanks for the advice. I think I will stay stay away from "USB memory stick for .system" for now.

Right now I'm bit surprised how silent the WD red disk are so I think I will keep my .system dataset on my main zfs-pool for now. The next step maybe will be to buy a SSD that could have the .system dataset together with some of my jail datasets that also are written to constant.

Joeschmuck: When you say that the .system dataset is written to every 10 seconds I take that as it is no use to configure a standby time on those disk. The will never go to standby anyway. Do I understand you correct then?

 

[cyberjock]

I said that they are written to every 10 seconds. So yes, configuring a standby time would be pointless(not to mention sleeping the disks isn't recommended).

 

[mblund]

great, thank again.

 

[joeschmuck]

Cyberjock said it was every 10 seconds, I was just acknowledging him. I run my drives all the time and have no ambition to relocate the .system files. If my heads move every 10 seconds, I'm actually pleased because that performs a service for me to reduce the wear leveling problems on the hard drive platters, even if it is a minor concern these days.

 

[cyberjock]

On my test box, with nothing using my test VM, zpool iostat 1 shows a 300kB write every 10 seconds.. and it goes to .system. :( The VM has been idle for almost an hour with no activity. Other users have also validated the 10 second thing(which is what lead me to the VM). I'm not sure what is being written in such large quantities but it's a problem that has been validated but not fixed. I'm not sure if a ticket exists or not for the issue, assuming it actually IS an issue. The logs go to .system for most users too, so it could be logs.

 

[joeschmuck]

On my test box, with nothing using my test VM, zpool iostat 1 shows a 300kB write every 10 seconds.. and it goes to .system. :( The VM has been idle for almost an hour with no activity. Other users have also validated the 10 second thing(which is what lead me to the VM). I'm not sure what is being written in such large quantities but it's a problem that has been validated but not fixed. I'm not sure if a ticket exists or not for the issue, assuming it actually IS an issue. The logs go to .system for most users too, so it could be logs.

It must be by design or I would assume (there I go making assumptions again) it would have been flagged as a problem.

 

[NetworkCo]

I am looking for a solution to this as well. I don't care if freenas logs anything at all, I was forced to add a disk just for system but what a waste. I'd prefer an option to log to /dev/null

 

[Yatti420]

What if you don't use the .system (aka memory device - old method).. Is it simply the old method with ramdisk or different now? Limited size ramdisk though right so logs turn over etc?

 

[NetworkCo]

Love this, I reverted to 8.x so I don't have to deal with FreeNAS using my storage drives for it's own purpose. This solved the issue with logging but I have another now in that certain RAID controllers won't allow FreeNAS to spin down drives attached to them

 

[cyberjock]

Love this, I reverted to 8.x so I don't have to deal with FreeNAS using my storage drives for it's own purpose. This solved the issue with logging but I have another now in that certain RAID controllers won't allow FreeNAS to spin down drives attached to them

Holy crap! The security risks you are taking... wowzers!

 

[NetworkCo]

How is 8.x a security risk?

 

[cyberjock]

How is 8.x a security risk?

Every vulnerability found in the FreeBSD release since FreeNAS 8.x is potentially included in that list. Do I need to say any more?

Would you use a Windows machine that hasn't been updated in 12+ months? Exactly.... ;)

 

[NetworkCo]

This thread has nothing to do with security

 

[cyberjock]

Oh.. sorry, so if you want to do something, even if its incredibly stupid, I shouldn't mention it because it's not what "this thread" is about!

Good luck to you! I'm sure you'll have many wonderful years with FreeNAS.. LOL!