mergemaster broken -- take 2

[Andrei Kolu]

Mike Lempriere wrote:
> Thanks everyone for the advice -- I got it working this time just 
> fine.  Works much better when one follows the directions accurately 
> instead of by memory -- the bottom line is that this time I remembered 
> to jot down the commands before heading downtown to the machine rack 
> room where there's no browser access...  I started over and followed 
> UPDATING:
>  cd /usr/obj
>  rm -R *
>  cd /usr/src
>  rm -R *
>  cvsup -g -L 2 -h cvsup10.freebsd.org |& tee /root/cvsup-090108.out
>  make buildworld |& tee /root/make-buildworld-090108.out
>  make kernel KERNCONF=GENERIC |& tee /root/make-kernel-090108.out
>  users
>  ps ax | more
>  shutdown -r now
You can go into single user without rebooting just by issuing command:

# shutdown now

NOTE: Network access will be shut down also, so you should be on your 
console then.

>  4 (single user)
>  fsck -p
>  mount -u /
>  mount -a
>  cd /usr/src
>  mergemaster -p
>  make installworld |& tee /root/make-installworld-090108.out
>  make delete-old (forgot to do tee redirect)
>  mergemaster -i (did not do tee redirect)
>  shutdown -r now
>
> Oliver Fromme wrote:
>> Greg Byshenk wrote:
>>  > Andrei Kolu wrote:
>>  > > Mike Lempriere wrote:
>>  > > > Hi folks -- sorry to be a nag, but my main production system 
>> is barely  > > > limping along on an old kernel with mismatched 
>> libraries.  I have no  > > > idea what else to do -- please help!
>>  > > > ---
>>  > > > I'm upgrading 5-stable (was at 5.5) to 6-stable, in 
>> preparation for  > > > 6-stable to 7-stable.
>>  > > > No problems with cvsup, make buildworld, make installworld, 
>> make  > > > buildkernel, mergemaster -p.
>>  > > > make installkernel, boot to single user.  Then mergemaster -- 
>> blammo:
>>
>> As others have pointed out, the order is wrong, which caused
>> the problem Mike is seeing.
>>
>> The correct order is listed in /usr/src/UPDATING.
>>
>>  > The reasons for the other methods being wrong are (as I understand 
>> them):
>>  >  > - You should build your new world before building your new 
>> kernel, as
>>  >   it may be the case that some aspects of the new kernel build are
>>  >   dependent upon aspects of the new world build.  If you build your
>>  >   new kernel before building your new world, you will be building 
>>  >   your new kernel against the old world.
>>
>> In particular, building the kernel uses the new toolchain
>> (i.e. compiler, linker, make(1) binary and so on) that was
>> built in /usr/obj during buildworld.  That's why you have
>> to do buildworld first, then "make kernel".
>>
>>  > - You should install your new kernel before installing your new 
>> world,
>>  >   as it can be the case that some aspects of the new world will 
>> not be
>>  >   understood by your old kernel. A new kernel should always be
>>  >   compatible with an old userland/world, but an old kernel may not 
>>  >   always be compatible with a new userland/world.
>>
>> That's correct.  Note that your kernel config should include
>> the appropriate "options COMPAT_*" lines if you update across
>> a major version boundary, e.g. "options_COMPAT_FREEBSD6" when
>> you update from 6.x to 7.x.  The GENERIC kernel already has
>> those.
>>
>>  > > NOTE: I do not reboot my system until everything is updated. Why 
>> it is  > > necessary to boot new kernel and then upgrade world is 
>> beyound me..YMMW
>>  >  > - I suppose that it is not strictly necessary to reboot between 
>>  >   installing kernel and world, but I always do so.
>>
>> It _is_ necessary.  If you don't reboot, you're still running
>> the old kernel which might not be able to support new binaries
>> and libraries that installworld will install on your system.
>>
>> For example, there may be new syscalls that the new binaries
>> will try to use, but the old kernel doesn't know about them.
>> It doesn't happen often, so you can get away without rebooting
>> most of the time.  But it's risky, especially when updating
>> across major versions.  So the recommendation is to always
>> reboot after installing the new kernel and before performing
>> the "installworld".
>>
>> It's also important that "installworld" is the last step
>> (except for mergemaster), because this is the point of no
>> return.  As long as you still have the old userland (world),
>> you can still boot the old kernel and everything is fine.
>> You can start all over froms cratch, if necessary.
>> But as soon as you have started "installworld", your system
>> will not be able to work with the old kernel anymore.
>>
>> And remember:  Always make a backup before you start to
>> update.  And verify that the backup works.  Better safe
>> than sorry.
>>
>> Best regards
>>    Oliver
>>
>>   
>