[lsst-dm-stack-users] How to update a stack release

[Kian-Tat Lim]

Dominique,

> I tried to follow it but ran into problems, so I tried to restart
> from scratch but even if I re-download everything lsst_build keeps
> claiming that some packages are already installed.
> Is there an option to clear everything completely and rebuild from scratch ?

	There are three things here: 1) getting the correct version of
the source, 2) building from source to installable packages, and 3)
installing the packages in your eups stack.  lsst-build is supposed to
minimize the amount of cloning for #1 and minimize the building for #2.

	If packages are already installed, those should be OK to use.
If you have changed the source (either manually or via "lsst-build
prepare --ref="), the version number of the package installed in the
eups stack should be different.

	If you think you have package versions installed that you don't
want, you can use "eups remove" to get rid of them, but you have to have
removed all packages dependent on them first.  Generally this shouldn't
be necessary.

	You can clear out the entire build directory used for #1 and #2
above by just removing it.  There is no other state.  You can also just
start a new build directory.

	Clearing out your entire eups stack can also be done by just
removing its directory and restarting from newinstall.sh (in a fresh
shell).  You can also aim newinstall.sh (again in a fresh shell) at a
new stack directory.

	Perhaps a log of the errors you are seeing would help?

-- 
Kian-Tat Lim, LSST Data Management, ktl at slac.stanford.edu