[et-mgmt-tools] boot locally after install via cobbler

[Peter Wright]

Michael DeHaan wrote:
>
> Michael DeHaan wrote:
> > Peter Wright wrote:
> >> Harry Hoffman wrote:
> >>>
> >>> Hi Peter,
> >>>
> >>> No, I don't think that'll work... but if you wrote a quick cgi to
> >>> accept
> >>> the args of mac addr and netboot then you could exec the cobbler
> >>> command...
> >>>
> >>> something like
> >>>
> >>> %post
> >>>
> >>> wget
> >>> 
> http://cobbler/cgi-bin/done_install?mac=00:11:22:33:44:55&netboot=n 
> <http://cobbler/cgi-bin/done_install?mac=00:11:22:33:44:55&netboot=n>
> >>> 
> <http://cobbler/cgi-bin/done_install?mac=00:11:22:33:44:55&netboot=n 
> <http://cobbler/cgi-bin/done_install?mac=00:11:22:33:44:55&netboot=n>>
> >>>
> >>> You'd of course want to do the normal sanitization of user data.
> >>>
> >>> I've got a script that I could modify to do this, let me know if you
> >>> need/want it.
> >>>
> >>> Cheers,
> >>> Harry
> >>>
> >>
> >>
> >>
> >> ok - i think i'm getting this thing now.  nice - if you don't mind
> >> posting that script i'd love to take a look at it.
> >>
> >> -p
> >>
> > Harry has the right idea -- still though, CGI scripts should be
> > running as the apache user and not root.   This means they won't (by
> > design) have access to modify the cobbler configuration.   What you
> > would really want to do is write a simple script that can /only/
> > disable the netboot field and then grant SSH access for only that one
> > command.   There is some example of that technique posted here, which
> > I personally haven't used, but I have it on good authority that it
> > works well :)
> >
> > http://www.mythic-beasts.com/support/dyndns_howto.html
> >
> > This way (writing a script that calls "cobbler system edit --name=name
> > --netboot-enabled=0") you make sure you've allowed remote access to
> > changing only that one
> > specific flag.   (This particular flag has the result of removing the
> > per-system configuration file in /tftpboot that enables the system to
> > boot to a specific PXE target)
> >
> > Incidentally, Matt Hyclak wrote a script to do this before you could
> > do this in the cobbler command line.  That script is mentioned on this
> > page:
> >
> > https://hosted.fedoraproject.org/projects/cobbler/wiki/CobblerApi
> >
> > The alternative is to SSH is to make the cgi to do this setuid root,
> > which has security implications.
> >
> > Another (perhaps simpler) option is set network boot lower in the BIOS
> > order (so hard drives first), and then when it comes time to reinstall
> > them, you can use
> > "koan --replace-self --server=bootserver.example.com --profile=name"
> > to do the reinstall rather than needing to PXE.  If the Linux box is
> > already running, you can invoke that koan call over SSH followed by a
> > call to /sbin/reboot.    That will essentially do the same thing, and
> > is what I do and generally recommend.
> >
> >
>
> Talking on IRC,
>
> We've decided we're going to implement the following:
>
> When /var/lib/cobbler/settings parameter "pxe_just_once" is set to 1,
> we're going to add a line to the bottom of the kickstart to call
> a CGI script.   (You'll also have to add a sudoers entry that we can
> define in the manpage)
>
> There's going to be a wget to a CGI script that takes a cobbler system
> name as a parameter.
> This script invokes cobbler_set_netboot via sudo, which can do nothing
> else but toggle the netboot-enabled parameter.
> cobbler_set_netboot has permissions to only toggle the netboot flag
>
> So, in summary, all a user will need to do is:
> -- flip the pxe_just_once switch in the settings file
> -- add a sudoers entry (cobbler check can even show the user what this
> entry must look like)
>
> We can do this :)
>


OK, this sounds like a reasonable solution for me, thanks all!

-pete


-- 
Peter Wright
Systems Administrator
Sony Pictures Imageworks
wright at imageworks.com
www.imageworks.com