[OLPC-AU] Golden image restores for laptops in shared use scenarios
James Cameron
quozl at laptop.org
Tue Jan 18 00:05:11 EST 2011
Occasionally a laptop operating system needs to be reinstalled for
testing, or where the laptop is transferred to another owner, or where
the laptop is shared as a teaching resource.
Reinstalling in the supported fashion costs roughly 20 minutes on an
XO-1.5, due to the complete block by block rewrite of the internal SD
card.
Reinstalling a batch of laptops costs 20 minutes for the first one, then
roughly 50 minutes for the rest, using NANDblaster.
An alternative to a complete rewrite is a filesystem synchronisation,
from a master filesystem to the target laptop. Only the changes
necessary are sent over the wireless. This costs about four minutes per
laptop using the tools I've just written.
Usage scenario:
1. boot a master laptop that contains a pristine filesystem (or place
a copy of the filesystem on a server),
2. for each target laptop, boot using a USB drive, remove the drive,
and start a script "xo-server".
More detail and tested procedure at:
http://wiki.laptop.org/go/Tiny_Core_Linux/Reversion
Risks:
- filesystem corruption of the master laptop would be copied to the
other laptops,
- accidental boot of the master laptop may cause side-effects such as
loss of collaboration in Sugar,
- minor differences in filesystem allocation may occur, but since the
internal storage is non-rotating there should be no significant change
to activity response times.
- not supported by OLPCA's deployment support team.
--
James Cameron
http://quozl.linux.org.au/
More information about the OLPC-AU
mailing list