View previous topic :: View next topic |
Author |
Message |
kolcon Tux's lil' helper
Joined: 21 Sep 2007 Posts: 96 Location: Europe, CZ
|
Posted: Sun Aug 08, 2010 8:50 pm Post subject: 32bit -> 64bit without downtime |
|
|
Hello,
I have a server currently running 32bit Gentoo.
Say I would like to migrate it to 64bit (the CPU is capable of it).
Is it possible to do a chroot install? I would like to minimize the downtime.
Or - perhaps - somehow - compile 64bit kernel, reboot (minimal downtime) and then
continue building the chroot?
Thank you
Lubos |
|
Back to top |
|
|
NeddySeagoon Administrator
Joined: 05 Jul 2003 Posts: 54237 Location: 56N 3W
|
Posted: Sun Aug 08, 2010 9:00 pm Post subject: |
|
|
kolcon,
You can't do a 64 bit chroot install while you run a 32 bit kernel.
You also need to swap your toolchain in one go. A mix of 32 bit and 64 bit is horribly broken.
Lastly, the /lib layout is different as 64 bit installs have some 32 bit libs, so they can run 32 bit software.
It will be much less pain, and probably faster, to reinstall _________________ Regards,
NeddySeagoon
Computer users fall into two groups:-
those that do backups
those that have never had a hard drive fail. |
|
Back to top |
|
|
kolcon Tux's lil' helper
Joined: 21 Sep 2007 Posts: 96 Location: Europe, CZ
|
Posted: Mon Aug 09, 2010 10:43 am Post subject: |
|
|
NeddySeagoon wrote: | kolcon,
You can't do a 64 bit chroot install while you run a 32 bit kernel.
You also need to swap your toolchain in one go. A mix of 32 bit and 64 bit is horribly broken.
Lastly, the /lib layout is different as 64 bit installs have some 32 bit libs, so they can run 32 bit software.
It will be much less pain, and probably faster, to reinstall |
OK, I understand. I will postpone the migration to 64bit then, as it would probably not give
any real benefits anyway. Will just wait for new machine and then do it clean. |
|
Back to top |
|
|
neuron Advocate
Joined: 28 May 2002 Posts: 2371
|
Posted: Sun Sep 05, 2010 4:20 pm Post subject: |
|
|
You can probably setup a generic 64bit build in a virtual machine and move that over afterwards. Then rebuild the system with the right cflags after. |
|
Back to top |
|
|
chithanh Developer
Joined: 05 Aug 2006 Posts: 2158 Location: Berlin, Germany
|
Posted: Sun Sep 05, 2010 6:40 pm Post subject: |
|
|
It is possible with minimal downtime if your kernel supports kexec(). But it requires some preparation. Basically the steps are as follows:
- Install a 64 bit kernel using crossdev or similar
- kexec() to your 64 bit kernel
- Build a 64 bit system in chroot
- Switch to your new system using busybox switch_root
Steps 2 and 4 need to be done from single user mode. Probably it would be a good idea to exercise all steps in a test environment before applying to a production system. |
|
Back to top |
|
|
Corona688 Veteran
Joined: 10 Jan 2004 Posts: 1204
|
Posted: Fri Sep 10, 2010 3:44 am Post subject: |
|
|
kolcon wrote: | OK, I understand. I will postpone the migration to 64bit then, as it would probably not give
any real benefits anyway. Will just wait for new machine and then do it clean. | I had to sneakernet a disk home recently to fsck it, the 32-bit machine couldn't do so without running out of virtual memory. _________________ Petition for Better 64-bit ATI Drivers - Sign Here
http://www.petitiononline.com/atipet/petition.html |
|
Back to top |
|
|
|