Re: [gentoo-user] X-forwarding fails with "Invalid MIT-MAGIC-COOKIE-1 key"

[Alan McKinnon]

On Saturday 25 April 2009 19:25:26 Grant wrote:
> >> X-forwarding used to work for me but I haven't used it in a while and
> >> now I get:
> >>
> >> Warning: untrusted X11 forwarding setup failed: xauth key data not
> >> generated
> >> Warning: No xauth data; using fake authentication data for X11
> >> forwarding. Xlib: connection to "localhost:10.0" refused by server
> >> Xlib: Invalid MIT-MAGIC-COOKIE-1 key
> >> Cannot open display:
> >
> > Ah, I had this problem for months; it was driving me crazy!
> >
> > I don't remember the specifics, but it had to to with some wankery of
> > glibc not working properly with xauth.  I'm pretty sure the fix is to
> > update to
> >
> >>=sys-libs/glibc-2.9_p20081201-r2 or regress glibc back a few ticks.
> >
> > Regards,
> > Wyatt
>
> Thanks Wyatt.  I upgraded the server and client to the latest glibc in
> portage with the same result.  When I tried to downgrade glibc, I got:
>
>  * Sanity check to keep you from breaking your system:
>  *  Downgrading glibc is not supported and a sure way to destruction

And there's a very good reason for that message - I'm sure you can figure it 
out. However, some downgrades are safe. You should be able to get away with 
downgrading to any lower version in the same minor release - 2.9 in your case.

Tip: quickpkg glibc, portage, python, gcc and other vital stuff befoore you 
try this stunt:

Edit the desired build, and look for this in pkg_setup():

if has_version '>'${CATEGORY}/${PF} ; then
	eerror "Sanity check to keep you from breaking your system:"
        eerror " Downgrading glibc is not supported and a sure way to 
destruction"
	die "aborting to save your system"
fi

Comment out the die call, re-digest, re-emerge.

The very very latest ebuild has it in files/eblits/pkg_setup.eblit instead, 
but you won't be using that for a downgrade.

-- 
alan dot mckinnon at gmail dot com