[OpenIndiana-discuss] Sending our zpool offsite using encrypted USB HDDs

[Thorsten Heit]

Hi,

> > # zfs send fs at snapshot | bzip2 -z -c | gpg -c --cipher-algo AES
> > --digest-algo SHA512 > /media/usb/stream.gpg
> 
> Based on performance characteristics, I would never recommend bzip2 
> for anything.  For most situations like this, fast compression would
> be more desirable (lzop is fastest, gzip --fast is second fastest) 
> ... bzip2 will both take longer and get less compression than xz --fast.
> 
> Better yet, as I mentioned in another message moments ago, you 
> really want to zfs receive on the destination disk.  You can simply 
> enable the compression property on the receiving filesystem (and 
> probably you want to set sync=disabled on the backup destination 
> too).  By default, zfs compression uses something that is similar to
> lzo (lzop) but if you wanted, you could make it use zlib (gzip) by 
> setting the compression property to the desired compressor 
> explicitly.  I don't think you'll benefit by doing so.
> 
> I think the best solution for this situation is simply to set 
> compression=on (and sync=disabled) on the receiving zfs filesystem.

Compression on the receiving file system doesn't impact the size of data 
transmitted by "zfs send..."; that's why I recommended to compress the 
data _before_ any transmission takes place.

I'm using bzip2 because it has better compression rates than gzip and 
because our company only uses fast ethernet although every PC has Gigabit 
NICs built in :-o

If you don't like bzip2, then use something else such as gzip, xz, ...


Regards

Thorsten