Re: [gentoo-user] Problems setting up sshd on an installation kernel

[Stroller <stroller@stellar.eclipse.co.uk>]

On 9 Dec 2009, at 19:42, Alan McKinnon wrote:
> ...
> Installation is supposed to be an atomic operation - it
> starts then continues till it ends. It either fully completes or is  
> considered
> to not have happened, meaning that persistence is diametrically  
> opposed to
> what an install is. It's analogous to a compile - terminating  
> compilation at
> some arbitrary point then picking up from where it ended at some  
> later point
> is just not supported. Possible yes, but not supported by default.

I'd disagree with you on that point, assuming I'm reading you right.

If a compile fails it shouldn't be an "unsupported" situation. One  
should be able to reemerge the package, possibly after emerging a  
required dependency first. That should work just fine (and surely it  
always does?).

Likewise it's not at all uncommon to make a mistake during the  
installation process - to miss out an essential kernel driver or  
package, and find that the installation fails to boot. The way I  
interpret your statement is that the supported remedy is to start  
again completely from scratch. Clearly this is not what one does - one  
boots again with the LiveCD, chroots into the installation, makes the  
fix and then reboots again to see if the system is now fixed. Every  
new Gentoo user has to do this a number of times, it is our standard  
advice to them, and we, as experienced users, will still have to do  
the same thing occasionally due to our own oversights.

However, I would agree with you that resolving Alan Mackenzie's  
problems with ssh should not be a priority. The "standard" procedure  
should be written for a user sitting in front of the machine on which  
Gentoo is being installed. Installing via SSH is an "advanced"  
procedure and should be considered to be undertaken by users who know  
what they're doing. The requirement to rarely remove a line from  
~/.ssh/known_hosts is really not much hassle.

I am somewhat surprised that Mr Mackenzie managed  to waste as much  
time as 10 hours attempting to SSH into the "wrong" environment, as it  
has never occurred to me to do it that way around, and Florian posted  
appropriate advice to resolve the problem less than 2 hours after  
Alan's original post.

I think this is typical of the kind of mistake we all make and learn  
from - we have all wasted 10 hours on some occasion, only to kick  
ourselves afterwards. When we do this we learn never again to make the  
same mistake.

On 9 Dec 2009, at 16:46, Alan Mackenzie wrote:
> However, setting up /dev completely (with --rbind) costs nothing, adds
> capability, and takes nothing away.

It is not clear to me that this is the "obvious" and "optimal"  
solution. It may be. I cannot foresee whether it may introduce side- 
effects.

Stroller.