Hi all,
We use webconverger as OS at the moment on 24 computers in several
classrooms. The OS is installed on a small harddisk. We change the
boot parameters without a complete build, following the instructions
on http://webconverger.org/develop/. We dump the isohybrid on a
harddisks using dd.
We were looking into an easier way to upgrade all the workstations to
a newer Webconverger version and came accross Trinity Rescue Kit. This
creates from a bootable CD-ROM an easy netboot server. Using the
mclone tool in the Kit, you can dd harddisks over the network on other
workstations using multicasting (takes about 35 seconds, whatever the
number of workstations).
Sounds all really cool, except that the cloned workstations at first
didn't boot. We noticed that parted doesn't like the iso-hybrid
partition either, so searched the problem in the direction of the iso-
hybrid partition Webconverger resides on.
After some research, we found that you should make the iso bootable
with the -offset 1 option of isohybrid, e.g.
isohybrid -offset 1 custom.iso
It might be good to add something about this to the documentation. It
can also stay here to google up for future reference. I have no idea
if more people want to keep a large amount of Webconvergers up to
date.
Thanks a lot for this great piece of software!
Koen
Wow, thanks for writing in Koen. That sounds really really awesome.
So are are your terminals configured to boot PXE by default?
So I guess you don't put your netboot upgrade server online on your network, unless you want to upgrade?
If you register on the Wiki via http://webconverger.org/ikiwiki.cgi?do=prefs I can give you admin rights to edit the Wiki. I can also give you edit rights via a ssh pub key & git.
It would be great if you could document the whole setup (with photos :) on the wiki. Else at the very least you could use gist.github.com and I can merge it in via git.
So I'm planning to add some persistence layer in USB images and use the existing squashfs as a rsync base for a new update squashfs. I guess at some point it efficiently downloads the new squashfs in the background, come release. Then it scripts the boot command line to boot into the updated squashfs, and if that for some reason it fails, allow it to fall back to the old squashfs. A bit like how most distros treat a Linux upgrade at present. That's the rough idea at present. I like to think of deployment of customised Webconvergers in terms of a squashfs unit, as it makes things easy at least for my brain. :}
On 10 feb, 02:44, Kai Hendry <hen...@webconverger.com> wrote:
> So are are your terminals configured to boot PXE by default?
No, we just change the boot order during upgrade
> So I guess you don't put your netboot upgrade server online on your
> network, unless you want to upgrade?
Yes. The netboot upgrade server is nothing more then a CD to boot from
- really convenient. We are thinking of booting over the network for a
screen cast system, since the screens can end up on difficult to
access places (with ladders and stuff ;-) ), but that is for much
later - the backend still has to be build.
I registered in the wiki
I like the save approach for the upgrade process. Would be a great
feature!
On Fri, Feb 10, 2012 at 9:25 AM, koenr <koen.roggem...@gmail.com> wrote: > - really convenient. We are thinking of booting over the network for a > screen cast system, since the screens can end up on difficult to > access places (with ladders and stuff ;-) ), but that is for much > later - the backend still has to be build.
As far as I can remember, you can build debian live (and hence Webconverger) for netbooting, or it's a boot option of a kind where you can have your image boot from a simple http:// location.
I like the netboot & dd local disk on demand idea.
People do ask for netboot customisations, but traditional netboot where images are loaded everytime imo sucks big time (far too fragile) and hence I don't offer it.
Oh btw, did you have to do some special tweaking to enable multicasting?
> I like the save approach for the upgrade process. Would be a great > feature!
Not sure what you mean by the "save" approach, do you mean "safe"? :)
> As far as I can remember, you can build debian live (and hence Webconverger) > for netbooting, or it's a boot option of a kind where you can have your > image boot from a simple http:// location.
I've forgotten about this almost, but yes you could have a netboot setup, whereby every terminals boot configuration has (something like) this line:
Making it download the squashfs IIRC (haven't tested it for ages). This sort of deployment could be sped up I assume with a transparent proxy and maybe some "multicasting" switch, but I haven't tried.
I prefer Koen's netboot then dd to disk process at present. Though maybe I can at revisit with httpfs= with persistency in mind...
