dhc* in NetBSD 7.0

[Jeff Rizzo <riz%NetBSD.org@localhost>]

Prompted by the "dhclient" discussion that just came up on 
current-users, I'd like to get the ball rolling on deciding how to move 
forward on support for dhcp in NetBSD 7.

As it stands, we have two dhcp clients in base:  an old (3.x) version of 
ISC's dhclient, and a much newer, well-supported dhcpcd. dhcpcd is much 
more full-featured than the version of dhclient that we have - so it 
would seem to be a good choice going forward, except for the dhcp 
*server* issue.  NetBSD has included a dhcp server in base since at 
least 1996 (I didn't check further back), but it's not entirely clear to 
me that we *need* a dhcp server in base;  this would seem to be a 
perfect application for pkgsrc.  (Indeed, I needed some newer features 
than the one we have in base, so I installed ISC dhcp 4.x from pkgsrc, 
and it works well)

At the very least, we should not be shipping code that upstream no 
longer supports - we have DHCP 3.x, which was desupported by ISC over a 
year ago.  (Actually, I believe the specific version we have lost 
support even sooner).  I see a few different options, and would like to 
know people's thoughts on how to proceed:

1) Remove ISC DHCP from base entirely;  this would mean NetBSD 7.0 would 
not ship with a DHCP server, and would have dhcpcd as the only DHCP 
client in base.

2) Update ISC DHCP in-tree and continue supporting dhclient, dhcpd, AND 
dhcpcd.  This will require a fair amount of work to discover the various 
reasons we've stuck with 3.0.3, and address these concerns. If we choose 
this path, we should update to the latest version with "Extended 
Support" at the time of branching and/or during the beta period - we 
want to make sure 7.0 has a good long life.

3) Update ISC DHCP as per item 2, but don't build/install dhclient by 
default.  Why do we need two DHCP clients in base?

4) Update ISC DHCP, and remove dhcpcd from base.  (I personally don't 
like this option at all, nor do I expect it to be the choice, but I 
include it here for completeness).

5) Some Other Option that I've missed here.

I would love to be enlightened as to any issues I may have missed, or 
glossed over.  Anyone with relevant input, please speak up!

+j