volume/dataset on usb key where FreeNAS is installed

[fabads]

Hi,

I've installed FreeNAS on a USB key (on a HP N40L). Is it possible to install some applications on this USB key to avoid using hard drives? For example, I have a dedicated application, running every 15 minutes (crontab), in charge of retrieving some data on an external equipment. It could be interesting for me to install this app on this usb key and keep my hard drive idle (or hibernated if possible).
In the same way, is it possible to install jail on this usb key (I plan to install Logitech Media Server as explained in a post of this forum, requiring jail installation).

Any help appreciated (and I'm new to Freenas, so maybe asking stupid questions !).

Regards.

Fabrice

 

[cyberjock]

Installing a jail on a USB key has been discussed before. Protosd told someone that doing it was stupid because it would wear out the USB key quickly. The person did it anyway and in a week was back in the forum complaining because his FreeNAS server paniced and when he rebooted FreeNAS wouldn't load. I was glad to see that guy get flamed. If you don't want to listen to the developers then don't expect sympathy when you do exactly what they told you not to do.

There's VERY little free space on the FreeNAS installation for anything else. Aside from wearing out the USB key you will likely find yourself out of space. I'd just install it to a hard disk and be done with it. Not to mention that anything you put on the USB key may be lost when you do an update.

 

[joeschmuck]

I use a separate USB flash drive for scripts and data I'd like to run just to keep them off my hard drives so they can stay sleeping. I retain a backup copy of these scripts on my hard drives just in case something happens to the flash and then I can quickly recover from it.

I highly recommend going this route for what you're planning.

Something that collects data every 15 minutes? Are you storing that data anywhere?

If you are just reading the Flash drive, this will not impact the life of the flash drive, however if you plan to write to it then that impacts the life of the drive. I would never recommend using the boot flash drive for anything.

I use a 32GB Flash drive for my data and it's formatted in UFS vice ZFS, you can use either but ZFS is slightly slower. Mount this as a drive and then you have some extra play room and it's easy to access and manipulate. Now I don't even touch the 32GB capacity that I have but I could use that for storing files for an FTP or Web Servers and thus keeping my hard drives sleeping. Lets face it, the internet is slower than even the slow USB flash drives. My cost for that drive (discontinued now) was $21.59 delivered to my door. If you already have a USB drive which will do your job, then I recommend you try it.

-Mark

 

[paleoN]

Installing the jail itself to the Flash drive will cause writes every 5 minutes. See ticket #1681.

 

[joeschmuck]

Installing the jail itself to the Flash drive will cause writes every 5 minutes. See ticket #1681.

This ticket doesn't say there is writing every 5 minutes to the jail, just that the /var/log/cron is logged. /var is in RAM unless I'm wrong and I have been wrong in the past.

If I overlooked something please point it out, it would be valuable to know if the jail is being written to frequently under any normal situation.

 

[paleoN]

If I overlooked something please point it out, it would be valuable to know if the jail is being written to frequently under any normal situation.

AFAICT, the jail has a 'single' mount for / set to the plugins jail path. There are also a couple of nullfs mounts, in the base system, for the plugins & pbi directories in the jail path to the archive path.

Inside the jail /var is a normal directory under / which is on whatever drive the jail path is on.

Given that nullfs mounts work with the jail, you could always mount something else, e.g. another md drive, over the jails /var directory among other things.