Command-line version of XBian-copier

[mk01]

(1st Mar, 2014 06:34 AM)palswim Wrote:  

(1st Mar, 2014 06:29 AM)IriDium Wrote:  You are trying to invoke a command that was never intended, nor tested, to be invoked from the command line, so I'm not surprised you are encountering problems.

I had the problems using the "XBian copier" entry in the XBian-config utility. I'll have to verify more, but the command line seems to have worked better for me.

@palswim

the middleware is btrfs-auto-snapshot script which uses few different approaches. base idea for cloning btrfs is of course to use the native btrfs send | btrfs recv (it is atomic, copied are data streams not files so it is faster, supports incremental sends (on CoW the data saved since last send).

the img is created as:
1) file is created
2) file is truncated do needed size (size prealocation)
3) in the file 2 partitions are created (/boot and /btrfstop
3a) the parts are mounted via loop devices
4) into /boot /boot is copied and cmdline.txt adapted
5) btrfs send | btrfs recv is used to copy all found subvolumes
6) done

by default size of img is defined as used space reported by df (which unnecessary allocates waste space used by local snapshots which are NOT copied) + 500MB.

this size can be overriden on command line --size

check

Code:

btrfs-auto-snapshot --help

currently I added copying even from ANY filesystem to ANY files-system (via tar | tar -x) but because of formatting of dest partition only ext2/3/4 f2fs nfs is tested and paired with mkfs. this universal copy-to-copy is in /usr/local/include/xbian-config/modules/xbiancopy/main as one function.

btrfs-auto-snapshot is meant as universal snapshot management tool (cross platform). so xbian specifis are kept at xbian-config side, if needed actions resolve to btrfs & snapshots, btrfs-auto-snapshot is called.