taken from: http://wiki.debian.org/LTSP/Upgrading_4.2

Upgrading from LTSP 4.2

there are some differences between LTSP 4.2 and the LTSP5 implementation in debian.

you may want to move your LTSP 4.2 installs aside to /opt/ltsp-4.2 so that you can easily switch back if needed.

there is no lts.conf by default. it is only needed if you need to change defaults.

lts.conf:

LOCAL_STORAGE has been renamed LOCALDEV

configuring by hostname is broken due to [WWW] http://bugs.debian.org/406366

SCREEN_01 through SCREEN_06 should not be used, unless conflicting entries in /opt/ltsp/ARCH/etc/inittab are disabled.

ltspfs:

drives are now mounted at /media/USERNAME
