On Sun, May 08, 2022 at 11:24:12AM -0400, Michael Stone wrote:
> [apologies to package aliases getting this twice due to autocomplete fail]
> I've been trying to make sense of the NEWS item in isc-dhcp-client (that
> alternatives are needed) in combination with the functionality of ifupdown
> and what the implications are for debian upgrades generally.
> isc-dhcp-client as of the last upgrade is telling users to stop using it
> (the default dhcp client for debian).
> ifupdown (the traditional tool for managing networking on debian systems)
> has a Recommends on "isc-dhcp-client | dhcp-client". "dhcp-client" is a
> virtual package provided by "dhcpcanon" (version 0.8.5, which hasn't been
> touched in 4 years), "isc-dhcp-client", and "dhcpcd5" (which will trash a
> working configuration managed by ifupdown if installed, as it will try to
> take over interfaces currently set, e.g., to manual). This seems suboptimal
> at best.
> I believe that ifupdown will attempt to use udhcpd if installed, which
> should be a mostly-transparent change (except for the potential loss of
> lease information and any customization of dhclient scripts) but it isn't
> even on the ifupdown recommends list.
> ifupdown also (used to?) use pump, but that package went away a long time
> ago.
> So what's the path forward, maintaining compatibility and not breaking
> systems upgrading from current stable? Do we come up with a dhcpcd5 variant
> that *only* touches interfaces it is directed to touch via
> /etc/network/interfaces? Do we add udhcpcd to the "dhcp-client" virtual
> package and/or make it the default for ifupdown? Do we fork isc's dhcp suite
> and just continue to use dhclient? Revive pump? Something else?
Not an answer to your question, but a related issue I'll mention here.
Ubuntu no longer uses isc-dhcp by default, because it no longer uses
ifupdown; NetworkManager and networkd both have their own implementations of
dhcp clients which are used by preference. *However*, isc-dhcp is still
installed as part of all Ubuntu systems, because it is the only client
implementation that integrates with initramfs-tools
(/usr/share/initramfs-tools/hooks/zz-dhclient) so if you are using nfsroot
or any other network-based rootfs, it appears to still be the only game in
town. It would be a good idea to make sure as part of the deprecation of
isc-dhcp-client that we get initramfs integration of whatever is the
preferred replacement.
Well busybox's udhcpc would seem a likely candidate here -- but its IPv6 support (iirc the reason we switch to dhclient from klibc's ipconfig in Ubuntu's initramfs, at least) is described as incomplete.
Cheers,
mwh