FAIBASE/10-misc and hostname

[Thomas Neumann]

Hiya

[I'm not ~the~ Thomas, but I still want to answer.]

On Monday, March 11, 2013 06:15:13 PM Holger Parplies wrote:
> Some of these are FAI tasks, some are not. You can probably argue about
> whether hostname and /etc/network/interfaces are the responsibility of FAI
> or of the config space.

Then the wise master nodded and asked the initiate: What is an 'installation'?

Sorry, I just had to do it, because this issue felt like it needed a koan. 
Don't take it personally.

> [...] I'm sure there are reasons for what appears to me to be mixing up
> necessary installation steps and facultative installation steps in a FAIBASE
> class. I'd just like to understand them :).

Everything in FAIBASE _is_ optional and depends on your environment:
- partition layout (chroot / virtual containers)
- pre-seeding (may not even be possible (RPM?))
- packages (base image can contain everything)
- mountpoints (chroot / virtual containers)
- network interfaces (chroot / virtual containers)
- config files (handled via some other config management tool)

(The simple example features 2 hooks, but it wouldn't matter much if they were 
simply left out.)

FAI provides a low-level abstraction and the config space is the environment-
specific implementation. With the exception of installing a bootloader you can 
install a standalone client with just a bunch of text files (disk_config, 
packages, ...) and exactly two commands (fcopy /etc/network/interfaces and the 
one for setting the root password.)

The bootloader issue is pretty nasty though, because the 'correct' 
configuration is linked very tightly to the installed distribution, your 
environment and possibly even the underlying 'hardware'. (Installing a 
paravirtualised XenServer instance was a nightmare, because Citrix did not 
actually parse the bootloader, but circumvented grub completely instead read 
the menu.lst directly and expected to find specifically named boot configuration. 
Took a while to figure that one out...)

bye
thomas