Regularly updated files in /etc

[perryh at pluto.rain.com]

Peter Jeremy <peterjeremy at acm.org> wrote:

> - Moving dumpdates out of root just means a different FS would
>   need te be writable during dumps.

Said other FS would also need to be _mounted_ during all dumps that
either are incremental or specify -u; and it would ordinarily _not_
be mounted if one were following the classical advice to have the
system in single-user mode (with root remounted read/write to enable
writing to dumpdates) while running dump(8).  Granted that's no
longer supposed to be necessary if using -L, but not everyone trusts
UFS snapshots.

Since anyone who wants to move dumpdates elsewhere can easily enough
add -D to their dump(8) scripts, and/or put a symlink to the new
location in /etc, I don't know that there's a lot of upside to
changing its default location.

> resolv.conf is more problematic:
> - Potentially, it could be needed to NFS mount /var, though this
>   seems unlikely in practice.
> - Since there are no standard APIs for updating resolv.conf, there
>   are likely to be lots of home-grown scripts that know where it is.

I would be concerned about the first item (chicken-egg problem).
There would at least need to be an entry in UPDATING.

The last is easy enough to fix by dropping a symlink to the new
location into /etc, but as with dumpdates there is nothing stopping
someone who wants a read-only root FS -- and who doesn't need an
NFS-mounted /var -- from doing it on their own.