On Mon, 9 May 2022 at 08:07, Steve Langasek <vor...@debian.org> wrote:
> 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