Gotchas to Downgrade from 7.0-CURRENTto FreeBSD 6.1-PRERELEASE

[eculp at bafirst.com]

Quoting "M. Warner Losh" <imp at bsdimp.com>:

> In message: <20060311213529.epb13ogpggk00ws0 at mail.bafirst.com>
>            eculp at bafirst.com writes:
> : I've lost track a bit of the differences between current and
> : 6.1-prerelease.  I don't remember anything major that would cause
> : problems.  Does anyone know of a potential gotcha or have suggestions
> : the smooth the pathe or has done this since the freeze?
> :
> : The machine that I am going to downgrade is my wife's and I don't
> : really want to recompile roughly 540 ports that are installed but . . .
> : , if need be . . . . ;) Problems with the linuxpluginwrapper port in
> : current started this.  She likes to have her flash and pdf in the
> : browser even though all the other plugins that she uses work.  I think
> : she will probably prefer the stability of RELENG_6 in the long run.
>
> There are two areas where there will be problems.  First is shared
> libraries.  Many of them have, iirc, been bumped in -current.  Be
> careful here.
>
> Second, there may be kernel issues where while doing the downgrade you
> could hose yourself.  Esp in the area of mounting /.
>
> My suggestion is do the following for the downgrade (this order is
> different than a normal upgrade, and really isn't supported, so #2
> below is extra important):
>
> 	(1) Buildworld of RELENG_6
> 	(2) full dump, or cope w/o.
> 	(3) installworld of RELENG_6	Yes, before install kernel
> 	(4) install kernel
> 	(5) reboot
> 	(6) find all the shared libraries whose version has gone
> 	    backwards using ls -l and comparing times.  Delete new
> 	    versions.  They may interfere with new port building
> 	(7) Rebuild all ports from scratch.  Maybe consider installing
> 	    them from packages, or at least the portupgrade series.
> 	    make sure you force a recompile of all ports via portupgrade.
>
> If, at any point after #2 you are hozed, fall back to #2 and try
> again.  Alternatively, do a fresh install after #2 and grab your data
> files from step #2.  Build everything you need.
>
> : thanks for your warnings, observations and suggestions,
>
> I've done this half way between 6.0-RELEASE and today with a -current
> that was a little too green for the hardware it was on.  I was anal
> beyond belief to make sure that nothing from the date of the last
> -current install was left on the system after I was done.  The above
> is from memory, and your milage may vary.

Warner, thanks for confirming my concerns.  I'm going to give it a try 
and if it doesn't work, I'll just do a clean install and rebuild the 
ports.  That almost sounds like the best idea, more than anything else, 
for housecleaning but less fun ;).

>
> : PS.  BTW, there isn't a RELENG_6 ports tag, is there?  It is still
> : current, isn't it?
>
> /usr/ports isn't branched, but works on all /usr/src branches in
> question here (current and RELENG_6).

Thanks, for everything,

ed

>
> Warner
>