[gentoo-user] Transferring an existing install to new disk

[gentoo-user] Transferring an existing install to new disk

[Harry Putnam]

I should know how to do this but so many changes have happened
recently and I haven't done anything like this for a very long time.

My desktop version of gentoo is pretty far out of date.  And I think
there have been enough changes that I don't even want to try to get it
cleaned up.  

Rather, I'd like to build up a newly installed gentoo to the point
where it has all the stuff I want.  But do it inside a vmware virtual
machine. 

I'm trying to keep my working desktop in place until such time as the
vmware gentoo setup is ready

Once that install is up to speed with all my preferred apps in place.
And any kinks worked out...
Only then use it to overwrite my desktop OS.  Or reformat that disk
and move the vmware gentoo version to it.

The vmware gentoo would be guest on a windows XP pro machine.

I'd like to hear any comments concerning what problems I might run
into or whether the plan is likely to be a serious mess.

Also wouldn't mind seeing a rough outline of how to make that kind of
move. 

Re: [gentoo-user] Transferring an existing install to new disk

[Dirk Uys]

On Wed, Nov 12, 2008 at 9:35 AM, Harry Putnam <reader@newsguy.com> wrote:
> I should know how to do this but so many changes have happened
> recently and I haven't done anything like this for a very long time.
>
> My desktop version of gentoo is pretty far out of date.  And I think
> there have been enough changes that I don't even want to try to get it
> cleaned up.
>
> Rather, I'd like to build up a newly installed gentoo to the point
> where it has all the stuff I want.  But do it inside a vmware virtual
> machine.
>
> I'm trying to keep my working desktop in place until such time as the
> vmware gentoo setup is ready
>
> Once that install is up to speed with all my preferred apps in place.
> And any kinks worked out...
> Only then use it to overwrite my desktop OS.  Or reformat that disk
> and move the vmware gentoo version to it.
>
> The vmware gentoo would be guest on a windows XP pro machine.
>
> I'd like to hear any comments concerning what problems I might run
> into or whether the plan is likely to be a serious mess.
>
> Also wouldn't mind seeing a rough outline of how to make that kind of
> move.

I've thought about this myself, but I think there are some issues. The
hardware that vmware can simulate are limited and may not match your
actual hardware. This does not mean it's impossible, but you may need
to set network, graphics ,etc up again once the system is transferred.

Guess the steps will be pretty much the same as for transferring
between partitions or similar machines
- make sure all the required modules for the target system is compiled
in the kernel.
- Update /etc/fstab to point to the correct devices.
- Update the grub.conf to pass the correct root. (btw, does anyone use
anything other than grub these days?)
- Use tar (with appropriate flags to keep permissions and symlinks in
place) to transfer all the files
- Install the bootloader on the target MBR

I may have missed a few things, but that's everything I currently remember.

Regards
Dirk

Re: [gentoo-user] Transferring an existing install to new disk

[Garry Smith]

Dirk Uys wrote:
> On Wed, Nov 12, 2008 at 9:35 AM, Harry Putnam <reader@newsguy.com> wrote:
>   
>> I should know how to do this but so many changes have happened
>> recently and I haven't done anything like this for a very long time.
>>
>> My desktop version of gentoo is pretty far out of date.  And I think
>> there have been enough changes that I don't even want to try to get it
>> cleaned up.
>>
>> Rather, I'd like to build up a newly installed gentoo to the point
>> where it has all the stuff I want.  But do it inside a vmware virtual
>> machine.
>>
>> I'm trying to keep my working desktop in place until such time as the
>> vmware gentoo setup is ready
>>
>> Once that install is up to speed with all my preferred apps in place.
>> And any kinks worked out...
>> Only then use it to overwrite my desktop OS.  Or reformat that disk
>> and move the vmware gentoo version to it.
>>
>> The vmware gentoo would be guest on a windows XP pro machine.
>>
>> I'd like to hear any comments concerning what problems I might run
>> into or whether the plan is likely to be a serious mess.
>>
>> Also wouldn't mind seeing a rough outline of how to make that kind of
>> move.
>>     
>
> I've thought about this myself, but I think there are some issues. The
> hardware that vmware can simulate are limited and may not match your
> actual hardware. This does not mean it's impossible, but you may need
> to set network, graphics ,etc up again once the system is transferred.
>
> Guess the steps will be pretty much the same as for transferring
> between partitions or similar machines
> - make sure all the required modules for the target system is compiled
> in the kernel.
> - Update /etc/fstab to point to the correct devices.
> - Update the grub.conf to pass the correct root. (btw, does anyone use
> anything other than grub these days?)
> - Use tar (with appropriate flags to keep permissions and symlinks in
> place) to transfer all the files
> - Install the bootloader on the target MBR
>
> I may have missed a few things, but that's everything I currently remember.
>
>
>   
Harry was asking about going between two machines. I did something 
similar recently ((http://blog.garrysmith.net/?p=62#more-62)  and used 
the following command to pass the output from tar directly to the 
destination machine over SSH:

tar -cvzpf - ./bin ./boot ./dev ./etc ./lib ./lost+found ./media ./mnt 
./opt ./proc ./root ./sbin ./sys ./usr ./var | ssh -p8889 
root@192.168.1.69 “cd /mnt/gentoo; tar -xzpf -”

Unfortunately the symbolic links all came out as 0  byte files (not sym 
links), so in the end I fell back on rsync (over SSH) which did the job.

How do you normally preserve symlinks using tar piped over SSH?

An example of the rsync command I used was:

 rsync -avpe "ssh -p 8889" /home user@destination.machine:/mnt/gentoo


The next time that I do this, I will just use rsync straight away and 
not use tar. The Gentoo Live CD has rsync (the Gentoo minimal install 
doesn't), so you should use the former (I booted both machines (one of 
them within VMWare fusion) from live the CD in order to do the copy.


cheers

Garry

Re: [gentoo-user] Transferring an existing install to new disk

[Daniel Pielmeier]

2008/11/12 Garry Smith <garry.smith@computer.org>:
>
> tar -cvzpf - ./bin ./boot ./dev ./etc ./lib ./lost+found ./media ./mnt ./opt
> ./proc ./root ./sbin ./sys ./usr ./var | ssh -p8889 root@192.168.1.69 "cd
> /mnt/gentoo; tar -xzpf -"
>
> Unfortunately the symbolic links all came out as 0  byte files (not sym
> links), so in the end I fell back on rsync (over SSH) which did the job.
>
> How do you normally preserve symlinks using tar piped over SSH?

I think the symlinks shouldn't get affected by the tar+ssh transfer.
There is some tar option that preserves stuff. Take a look at man tar.
I use tar to do regular backups of my complete system and restored it
at least one time without problems. When I am back home I can look up
the command I use.

-- 
Regards,
Daniel

Re: [gentoo-user] Transferring an existing install to new disk

[Neil Bothwick]

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On Wed, 12 Nov 2008 01:35:32 -0600, Harry Putnam wrote:

> Rather, I'd like to build up a newly installed gentoo to the point
> where it has all the stuff I want.  But do it inside a vmware virtual
> machine. 
> 
> I'm trying to keep my working desktop in place until such time as the
> vmware gentoo setup is ready

If you're installing to a new disk, do a standard Gentoo install to that
disk, but do it from your working setup  instead of the live CD
environment. Your existing installation has all the tools you need to
build a new setup in a chroot.


-- 
Neil Bothwick

It's is not, it isn't ain't, and it's it's, not its, if you mean it
is.  If you don't, it's its.  Then too, it's hers.  It isn't her's.  It
isn't our's either.  It's ours, and likewise yours and theirs.
		-- Oxford University Press, Edpress News

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[gentoo-user] Re: Transferring an existing install to new disk

[Harry Putnam]

Neil Bothwick <neil@digimed.co.uk> writes:

> If you're installing to a new disk, do a standard Gentoo install to that
> disk, but do it from your working setup  instead of the live CD
> environment. Your existing installation has all the tools you need to
> build a new setup in a chroot.

I'm having a bit of a thick skulled problem understanding what you
mean above.

I can't think of how I would do a fresh install to a new disk from a
working vmware guest on a different machine or even on the same
machine for that matter.

Can you explain a few details... maybe I'll catch on.

Re: [gentoo-user] Re: Transferring an existing install to new disk

[Neil Bothwick]

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On Wed, 12 Nov 2008 08:03:51 -0600, Harry Putnam wrote:

> > If you're installing to a new disk, do a standard Gentoo install to
> > that disk, but do it from your working setup  instead of the live CD
> > environment. Your existing installation has all the tools you need to
> > build a new setup in a chroot.  
> 
> I'm having a bit of a thick skulled problem understanding what you
> mean above.
> 
> I can't think of how I would do a fresh install to a new disk from a
> working vmware guest on a different machine or even on the same
> machine for that matter.

The subject mentions a new disk, and your original post mentioned
installing anew for a machine you want to keep running, so I took it that
the new disk goes in the old computer.

So boot your existing Gentoo setup as usual, then follow the handbook to
install on the new disk. You do not have to boot from a live CD to
install Gentoo, and suitable working Linux environment will do the job,
and an existing Gentoo installation is more than suitable.


-- 
Neil Bothwick

Don't just read the Tagline; read the MESSAGE!

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Re: [gentoo-user] Transferring an existing install to new disk

[Alan Mackenzie]

Hi, Dirk, Hi, List!

On Wed, Nov 12, 2008 at 09:59:09AM +0200, Dirk Uys wrote:
> - Update the grub.conf to pass the correct root. (btw, does anyone use
> anything other than grub these days?)

Yes.  I use LILO.  My lilo.conf traces its ancestry back to my original
Linux installation, SuSE 5.3.

Why?  Because learning grub would take time.  Maybe not very much time,
but it would take some.  By contrast, although learning LILO took a very
great deal of time, that time is already spent, and can never more be got
back.  Putting an extra entry into lilo.conf and regenerating the boot
loader now takes, at most, a few minutes.

But if the motivation of your question is simplifying Gentoo by leaving
out LILO, that wouldn't bother me at all.  While I've still got a Debian
on my PC, I can use it to lie low, and when I need to learn grub, no big
deal.  In fact, by the time I get to learn grub, it will, in its turn,
probably have been superseded by something else.  :-)

> Regards
> Dirk

-- 
Alan Mackenzie (Nuremberg, Germany).

[gentoo-user] Re: Transferring an existing install to new disk

[Harry Putnam]

Neil Bothwick <neil@digimed.co.uk> writes:

> So boot your existing Gentoo setup as usual, then follow the handbook to
> install on the new disk. You do not have to boot from a live CD to
> install Gentoo, and suitable working Linux environment will do the job,
> and an existing Gentoo installation is more than suitable.

There still seems to be some misunderstanding.

I want to build up a fresh install somewhere besides my existing
desktop OS (gentoo).  Leave the existing setup alone for now.

Get the fresh install up to speed so it is a fresh and new
approximation of my desktop OS.  

And finally overwrite the desktop OS with the newly built one.
It sounds like what you are describing is just a new install using an
exiting gentoo os instead of install disk.

But the result would be a new install with nothing setup... on the
desktop which is not what I want.

Re: [gentoo-user] Re: Transferring an existing install to new disk

[Neil Bothwick]

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On Wed, 12 Nov 2008 09:51:12 -0600, Harry Putnam wrote:

> > So boot your existing Gentoo setup as usual, then follow the handbook
> > to install on the new disk. You do not have to boot from a live CD to
> > install Gentoo, and suitable working Linux environment will do the
> > job, and an existing Gentoo installation is more than suitable.  
> 
> There still seems to be some misunderstanding.
> 
> I want to build up a fresh install somewhere besides my existing
> desktop OS (gentoo).  Leave the existing setup alone for now.

Which is what a chroot install does.

> Get the fresh install up to speed so it is a fresh and new
> approximation of my desktop OS.  

Ditto.

> And finally overwrite the desktop OS with the newly built one.

Overwrite? Where does the new disk come into it then?

> It sounds like what you are describing is just a new install using an
> exiting gentoo os instead of install disk.
> 
> But the result would be a new install with nothing setup... on the
> desktop which is not what I want.

Obviously, you would set everything up, but it would be made easier by
the fact you are running on the target machine, and everything is in
place. There's no copying entire systems over, just change the bootloader
config when it's ready.


-- 
Neil Bothwick

Due to inflation, all clouds will now be lined with zinc.

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Re: [gentoo-user] Transferring an existing install to new disk

[Dale]

Alan Mackenzie wrote:
> Hi, Dirk, Hi, List!
>
> On Wed, Nov 12, 2008 at 09:59:09AM +0200, Dirk Uys wrote:
>   
>> - Update the grub.conf to pass the correct root. (btw, does anyone use
>> anything other than grub these days?)
>>     
>
> Yes.  I use LILO.  My lilo.conf traces its ancestry back to my original
> Linux installation, SuSE 5.3.
>
> Why?  Because learning grub would take time.  Maybe not very much time,
> but it would take some.  By contrast, although learning LILO took a very
> great deal of time, that time is already spent, and can never more be got
> back.  Putting an extra entry into lilo.conf and regenerating the boot
> loader now takes, at most, a few minutes.
>
> But if the motivation of your question is simplifying Gentoo by leaving
> out LILO, that wouldn't bother me at all.  While I've still got a Debian
> on my PC, I can use it to lie low, and when I need to learn grub, no big
> deal.  In fact, by the time I get to learn grub, it will, in its turn,
> probably have been superseded by something else.  :-)
>
>   
>> Regards
>> Dirk
>>     
>
>   


I started out with Lilo too. I can't recall why I switched but I did.
Grub is so much easier than Lilo. I have no regrets with switching and
would only use Lilo if it was all that was available.

The biggest thing to learn is the way the drives are listed. It uses
(hd0,0) and such. It's really not that hard once you get how it does it.
Also, it is real easy to switch to a older kernel at the grub boot
screen. Just edit the boot line and let it rip. You can also edit other
options for the boot line but changing kernels is the big one for me.

It's a thought.

Dale

:-) :-)

[gentoo-user] Re: Transferring an existing install to new disk

[Harry Putnam]

Neil Bothwick <neil@digimed.co.uk> writes:

> On Wed, 12 Nov 2008 09:51:12 -0600, Harry Putnam wrote:
>
>> > So boot your existing Gentoo setup as usual, then follow the handbook
>> > to install on the new disk. You do not have to boot from a live CD to
>> > install Gentoo, and suitable working Linux environment will do the
>> > job, and an existing Gentoo installation is more than suitable.  
>> 
>> There still seems to be some misunderstanding.
>> 
>> I want to build up a fresh install somewhere besides my existing
>> desktop OS (gentoo).  Leave the existing setup alone for now.
>
> Which is what a chroot install does.
>
>> Get the fresh install up to speed so it is a fresh and new
>> approximation of my desktop OS.  
>
> Ditto.
>
>> And finally overwrite the desktop OS with the newly built one.
>
> Overwrite? Where does the new disk come into it then?

New as in new to the built up install.  Perhaps a better choice would
have been `different disk'
>
>> It sounds like what you are describing is just a new install using an
>> exiting gentoo os instead of install disk.
>> 
>> But the result would be a new install with nothing setup... on the
>> desktop which is not what I want.
>
> Obviously, you would set everything up, but it would be made easier by
> the fact you are running on the target machine, and everything is in
> place. There's no copying entire systems over, just change the bootloader
> config when it's ready.

Ok, I see where your going here.... remove the notion of `new' disk.  
I don't have room for a new disk on the target machine, hence the idea
of overwriting.

But just talking about this much seems to indicate I'd be better off
braving up and trying to clean up my existing install.

Note a different thread where I've started on that mission:
 Subject: How to fix a hefty (emerge) blocking problem

To be posted shortly

Re: [gentoo-user] Re: Transferring an existing install to new disk

[Dale]

Harry Putnam wrote:
> Neil Bothwick <neil@digimed.co.uk> writes:
>
>   
>> So boot your existing Gentoo setup as usual, then follow the handbook to
>> install on the new disk. You do not have to boot from a live CD to
>> install Gentoo, and suitable working Linux environment will do the job,
>> and an existing Gentoo installation is more than suitable.
>>     
>
> There still seems to be some misunderstanding.
>
> I want to build up a fresh install somewhere besides my existing
> desktop OS (gentoo).  Leave the existing setup alone for now.
>
> Get the fresh install up to speed so it is a fresh and new
> approximation of my desktop OS.  
>
> And finally overwrite the desktop OS with the newly built one.
> It sounds like what you are describing is just a new install using an
> exiting gentoo os instead of install disk.
>
> But the result would be a new install with nothing setup... on the
> desktop which is not what I want.
>
>
>
>   

This may help.  You can install from the CD, another Gentoo system,
another Linux system with about any OS on it as long as it has chroot
and a couple other goodies.  I installed my Gentoo system from Mandrake
years ago.  As long as you can run chroot and a couple other goodies,
you can install.

Another thing I have done, put a hard drive in my main rig, install
Gentoo to run on another system.  After I get everything done, except
the boot loader, I put the drive in the new system, install the boot
loader and see if it boots or not. 

What people are saying is, there are a lot of ways to do what you are
wanting to do.  Gentoo is very flexible that way.  :-) 

Dale

:-)  :-) 

Re: [gentoo-user] Transferring an existing install to new disk

[Paul Hartman]

On Wed, Nov 12, 2008 at 11:50 AM, Dale <rdalek1967@gmail.com> wrote:
> Alan Mackenzie wrote:
>> Hi, Dirk, Hi, List!
>>
>> On Wed, Nov 12, 2008 at 09:59:09AM +0200, Dirk Uys wrote:
>>
>>> - Update the grub.conf to pass the correct root. (btw, does anyone use
>>> anything other than grub these days?)
>>>
>>
>> Yes.  I use LILO.  My lilo.conf traces its ancestry back to my original
>> Linux installation, SuSE 5.3.
>>
>> Why?  Because learning grub would take time.  Maybe not very much time,
>> but it would take some.  By contrast, although learning LILO took a very
>> great deal of time, that time is already spent, and can never more be got
>> back.  Putting an extra entry into lilo.conf and regenerating the boot
>> loader now takes, at most, a few minutes.
>>
>> But if the motivation of your question is simplifying Gentoo by leaving
>> out LILO, that wouldn't bother me at all.  While I've still got a Debian
>> on my PC, I can use it to lie low, and when I need to learn grub, no big
>> deal.  In fact, by the time I get to learn grub, it will, in its turn,
>> probably have been superseded by something else.  :-)
>>
>>
>>> Regards
>>> Dirk
>>>
>>
>>
>
>
> I started out with Lilo too. I can't recall why I switched but I did.
> Grub is so much easier than Lilo. I have no regrets with switching and
> would only use Lilo if it was all that was available.
>
> The biggest thing to learn is the way the drives are listed. It uses
> (hd0,0) and such. It's really not that hard once you get how it does it.
> Also, it is real easy to switch to a older kernel at the grub boot
> screen. Just edit the boot line and let it rip. You can also edit other
> options for the boot line but changing kernels is the big one for me.
>
> It's a thought.

I have my grub menu set up with 2 kernel choices; one points
to/vmlinuz and the other points to /vmlinuz.old, that way i don't ever
have to edit anything. Comes in handy if the new kernel blows up :)

Re: [gentoo-user] Transferring an existing install to new disk

[Dale]

Paul Hartman wrote:
>
> I have my grub menu set up with 2 kernel choices; one points
> to/vmlinuz and the other points to /vmlinuz.old, that way i don't ever
> have to edit anything. Comes in handy if the new kernel blows up :)
>
>
>   

I too have two entries.  One for the current kernel and one for the old
that I know works.  I do mine manually tho.  I don't do the install
thing.  I'm assuming you do tho.  ;-)  Here is a list of my old kernels:

root@smoker / # ls -al /boot/bzImage-2.6.2*
-rw-r--r-- 1 root root 2437912 2007-12-18 04:25 /boot/bzImage-2.6.23-r3-1
-rw-r--r-- 1 root root 2468952 2008-04-29 23:05 /boot/bzImage-2.6.23-r8-5
-rw-r--r-- 1 root root 2456984 2008-07-10 17:11 /boot/bzImage-2.6.23-r8-6
-rw-r--r-- 1 root root 2363676 2008-08-05 22:43 /boot/bzImage-2.6.25-r7-1
-rw-r--r-- 1 root root 2359548 2008-08-12 17:59 /boot/bzImage-2.6.25-r7-2
root@smoker / #

I'm still using the old 23 version.  The 25 version makes KDE and my
mouse VERY slow.  I hadn't had time to figure out why yet.

Dale

:-)  :-) 

Re: [gentoo-user] Transferring an existing install to new disk

[Michele Schiavo]

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I did it last week.

in some place untar che last stage3-xxx

mount --bind proc, dev, usr/portage, passwd, group ecc
copy inside current make.conf, make.profile
chroot inside the new stage.

when finish i make a big tar of everyone in the new chroot.
reboot with live cd, move all my old system in /old, untar the new
system on the rootfs.

if something is missing in the new system , you have the original file
of configuration in /old

P.S. sometime i make something like stage4 from livecd and i store it in
a USB HD.

If something is going wrong, in 20 min i can restore all my system.




Il giorno mer, 12/11/2008 alle 01.35 -0600, Harry Putnam ha scritto:

> I should know how to do this but so many changes have happened
> recently and I haven't done anything like this for a very long time.
> 
> My desktop version of gentoo is pretty far out of date.  And I think
> there have been enough changes that I don't even want to try to get it
> cleaned up.  
> 
> Rather, I'd like to build up a newly installed gentoo to the point
> where it has all the stuff I want.  But do it inside a vmware virtual
> machine. 
> 
> I'm trying to keep my working desktop in place until such time as the
> vmware gentoo setup is ready
> 
> Once that install is up to speed with all my preferred apps in place.
> And any kinks worked out...
> Only then use it to overwrite my desktop OS.  Or reformat that disk
> and move the vmware gentoo version to it.
> 
> The vmware gentoo would be guest on a windows XP pro machine.
> 
> I'd like to hear any comments concerning what problems I might run
> into or whether the plan is likely to be a serious mess.
> 
> Also wouldn't mind seeing a rough outline of how to make that kind of
> move. 
> 
> 
> 

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Re: [gentoo-user] Transferring an existing install to new disk

[Dirk Uys]

On Wed, Nov 12, 2008 at 4:54 PM, Alan Mackenzie <acm@muc.de> wrote:
> Hi, Dirk, Hi, List!
>
> On Wed, Nov 12, 2008 at 09:59:09AM +0200, Dirk Uys wrote:
>> - Update the grub.conf to pass the correct root. (btw, does anyone use
>> anything other than grub these days?)
>
> Yes.  I use LILO.  My lilo.conf traces its ancestry back to my original
> Linux installation, SuSE 5.3.
>
> Why?  Because learning grub would take time.  Maybe not very much time,
> but it would take some.  By contrast, although learning LILO took a very
> great deal of time, that time is already spent, and can never more be got
> back.  Putting an extra entry into lilo.conf and regenerating the boot
> loader now takes, at most, a few minutes.
>
> But if the motivation of your question is simplifying Gentoo by leaving
> out LILO, that wouldn't bother me at all.  While I've still got a Debian
> on my PC, I can use it to lie low, and when I need to learn grub, no big
> deal.  In fact, by the time I get to learn grub, it will, in its turn,
> probably have been superseded by something else.  :-)
>
>> Regards
>> Dirk
>
> --
> Alan Mackenzie (Nuremberg, Germany).

I was just curious. I like having choices, so I wouldn't opt for
leaving out LILO from gentoo.

Regards
Dirk

Re: [gentoo-user] Re: Transferring an existing install to new disk

[Peter Humphrey]

On Wednesday 12 November 2008 14:53:04 Neil Bothwick wrote:

> ... boot your existing Gentoo setup as usual, then follow the handbook to
> install on the new disk. You do not have to boot from a live CD to
> install Gentoo, [any] suitable working Linux environment will do the job,
> and an existing Gentoo installation is more than suitable.

Each of my five boxes has a small Gentoo rescue system in a spare partition, 
intended for just this kind of use. However, in every case, when I attempt 
to chroot into the main system from the rescue system I get a 
permission-denied error. Exactly the same chroot command works as expected 
if I've booted an installation CD.

Rather defeats the object of having a rescue system.

-- 
Rgds
Peter