# Should I turn my one disk/two zpool installation into a mirrored one?



## pvoigt (Oct 2, 2015)

On my FreeNAS machine I have recently turned my one disk ZFS stripe into a two disk mirror. I am very pleased with the ZFS mirror because I could increase data security without losing performance. Both the original stripe and the resulting mirror are GELI encrypted. I left the root file system on a one disk ZFS stripe untouched.

I am now thinking, if I should mirror my zpools on my FreeBSD 10.2-RELEASE server as well. Currently it has one disk hosting two zpools "zroot" and "zhome" with "zhome" being GELI encrypted. The situation differs from my FreeNAS system, because I am having two zpools that I would like to mirror, one of them hosting the root file system.

I have read a lot about ZFS and I have now hopefully collected enough knowledge to change to the mirrored zpools on the command line even without server down time. And to be on the safe side I will first test the procedure with a virtual machine.

However, I would like to collect some recommendations if I should go this way or not, because I am not sure, if performance is affected due to the fact that I am about to mirror two zpools on the two disks.

I am appreciating any comments or recommendations on this.

Peter


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## pvoigt (Oct 8, 2015)

I am wondering, if I did not provide enough details on my plans to increase data security without losing performance. I am just not experienced enough with ZFS and I would like to delay ordering a second hard disk until I know that it is a way to go. The situation under FreeNAS was easier for me  because there was just one zpool to be mirrored not carrying the root file system.

It is not easy to find information on my specific setup because most tutorials and FAQs cover just one zpool, either carrying the root file system or a data pool only.

Or are my thoughts going into a complete wrong direction?

I am appreciating any recommendations or links for further reading on this. Please let me know, if I should provide some more information.

Peter


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## pvoigt (Oct 28, 2015)

Meanwhile I have played with the FreeBSD installer on a virtual machine. I have found that a full disk encryption on a two disk ZFS mirror comes very close to my demands. Such an installation consists of two mirrored zpools one of which is GELI encrypted.

I have just turned my one disk FreeBSD installation of a VirtualBox virtual machine into a two disk ZFS mirror. It took me just one reboot after I changed the GPT labels. The root file system resides on an unencrypted zpool zroot while the home directory, e.g. /usr/home, is placed on a GELI encrypted zpool zhome. The whole conversion including resilvering and subsequent scrubbing went very smoothly.

Now I can dare to do the same on real hardware.

Peter


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