Re: [gentoo-user] Managing multiple systems with identical hardware

[Grant]

>>>> I realized I only need two types of systems in my life.  One hosted
>>>> server and bunch of identical laptops.  My laptop, my wife's laptop,
>>>> our HTPC, routers, and office workstations could all be on identical
>>>> hardware, and what better choice than a laptop?  Extremely
>>>> space-efficient, portable, built-in UPS (battery), and no need to buy
>>>> a separate monitor, keyboard, mouse, speakers, camera, etc.  Some
>>>> systems will use all of that stuff and some will use none, but it's
>>>> OK, laptops are getting cheap, and keyboard/mouse/video comes in handy
>>>> once in a while on any system.
>>>
>>> Laptops are a good choice, desktops are almost dead out there, and thin
>>> clients nettops are just dead in the water for anything other than
>>> appliances and media servers
>>>
>>>> What if my laptop is the master system and I install any application
>>>> that any of the other laptops need on my laptop and push its entire
>>>> install to all of the other laptops via rsync whenever it changes?
>>>> The only things that would vary by laptop would be users and
>>>> configuration.
>>>
>>> Could work, but don't push *your* laptop's config to all the other
>>> laptops. they end up with your stuff which might not be what them to
>>> have. Rather have a completely separate area where you store portage
>>> configs, tree, packages and distfiles for laptops/clients and push from
>>> there.
>>
>> I actually do want them all to have my stuff and I want to have all
>> their stuff.  That way everything is in sync and I can manage all of
>> them by just managing mine and pushing.  How about pushing only
>> portage configs and then letting each of them emerge unattended?  I
>> know unattended emerges are the kiss of death but if all of the
>> identical laptops have the same portage config and I emerge everything
>> successfully on my own laptop first, the unattended emerges should be
>> fine.
>
> Within those constraints it could work fine. The critical stuff to share
> is make.conf and /etc/portage/*, everything else can be shared to
> greater or lesser degree and you can undo things on a whim if you wish.
>
> There's one thing that we haven't touched on, and that's the hardware.
> Are they all identical hardware items, or at least compatible? Kernel
> builds and hardware-sensitive apps like mplayer are the top reasons
> you'd want to centralize things, but those are the very apps that will
> make sure life miserable trying to fins commonality that works in all
> cases. So do keep hardware needs in mind when making purchases.

Keeping all of the laptops 100% identical as far as hardware is
central to this plan.  I know I'm setting myself up for big problems
otherwise.

> Personally, I wouldn't do the building and pushing on my own laptop,
> that turns me inot the central server and updates only happen when I'm
> in the office. I'd use a central build host and my laptop is just
> another client. Not all that important really, the build host is just an
> address from the client's point of view

I don't think I'm making the connection here.  The central server
can't do any unattended building and pushing, correct?  So I would
need to be around either way I think.

I'm hoping I can emerge every package on my laptop that every other
laptop needs.  That way I can fix any build problems and update any
config files right on my own system.  Then I would push config file
differences to all of the other laptops.  Then each laptop could
emerge its own stuff unattended.

>> OK, I'm thinking over how much variation there would be from laptop to
>> laptop:
>>
>> 1. /etc/runlevels/default/* would vary of course.
>> 2. /etc/conf.d/net would vary for the routers and my laptop which I
>> sometimes use as a router.
>> 3. /etc/hostapd/hostapd.conf under the same conditions as #2.
>> 4. Users and /home would vary but the office workstations could all be
>> identical in this regard.
>>
>> Am I missing anything?  I can imagine everything else being totally
>> identical.
>>
>> What could I use to manage these differences?
>
> I'm sure there are numerous files in /etc/ with small niggling
> differences, you will find these as you go along.
>
> In a Linux world, these files actually do not subject themselves to
> centralization very well, they really do need a human with clue to make
> a decision whilst having access to the laptop in question. Every time
> we've brain-stormed this at work, we end up with only two realistic
> options: go to every machine and configure it there directly, or put
> individual per-host configs into puppet and push. It comes down to the
> same thing, the only difference is the location where stuff is stored.

I'm sure I will need to carefully define those config differences.
Can I set up puppet (or similar) on my laptop and use it to push
config updates to all of the other laptops?  That way the package I'm
using to push will be aware of config differences per system and push
everything correctly.  You said not to use puppet, but does that apply
in this scenario?

> I'm slowly coming to conclsuion that you are trying to solve a problem
> with Gentoo that binary distros already solved a very long time ago. You
> are forcing yourself to become the sole maintainer of GrantOS and do all
> the heavy lifting of packaging. But, Mint and friends already did all
> that work already and frankly, they are much better at it than you or I.

Interesting.  When I switched from Windows about 10 years ago I had
only a very brief run with Mandrake before I settled on Gentoo so I
don't *really* know what a binary distro is about.  How would this
workflow be different on a binary distro?

- Grant