[tech] Group/GID changes

[David Adam]

On Sun, 9 Nov 2014, David Adam wrote:
> Basically, most systems (including Debian) expect that there are some GIDs 
> which are used for one purpose, and we use them for another. For example, 
> 'gumby' (our general user group) is GID 21, which Debian expects to 
> actually be 'fax'. Mostly we have been hacking around this and hoping.
> 

> Notably, I am yet to fix the mess with the following groups:
> 
> gumby:x:21
> www-data:x:101
> other:x:70

Further to this, I have made a start on the GID 21 mess. I have tried to 
do it in such a way that nobody loses access to any data.

All gumby users have been added to both GID 21 (now called oldgumby) and 
GID 10021 (the new gumby group) as supplementary users. Also, everyone who 
had a primary group of GID 21 has had it changed to GID 10021.

I changed the Samba groupmap to make RID 513 (the Domain Users group) 
point to the new group ID.

Next time we reboot and kick the majority of user sessions off we can 
remove the GID 21 entry in LDAP.

[DAA]