[OpenIndiana-discuss] Split-root installations

[Peter Tribble]

On Tue, Nov 26, 2013 at 4:25 PM, Jim Klimov <jimklimov at cos.ru> wrote:

> On 2013-11-17 03:50, Jim Klimov wrote:
>
>>    For years I've mentioned "split-root" installations of Solaris-like
>> systems in such a way that the root filesystem (the BE) is represented
>> by several datasets, such as a split-off /usr dataset. Also there may
>> be some datasets shared between boot environments, such as the sinks
>> for logs and crashdumps, and not all of these are required to live on
>> the rpool at all. There are cases when all such tweaks may be desirable.
>>
>
> WARNING
>
> As discussed in another thread, it was discovered that the SMF methods
> for network/physical (both :default and :nwam) use many programs from
> /usr, and are executed before the /usr filesystem is actually mounted
> in case of a split-root installation. This tanks the NWAM setups, but
> the default ones (based on static files in /etc) succeeds for both DHCP
> and completely static addressing.
>

I'm not quite sure how much you need /usr early on, but it
wasn't that hard to PXE boot a minimal system and get it
to pull /usr over the network. (That's how AI works, as well,
so it's possible.) In many ways, the live boot is the classic
example of a separate /usr, so the logic there may be worth
studying - both for media and network boot.

-- 
-Peter Tribble
http://www.petertribble.co.uk/ - http://ptribble.blogspot.com/