Dear Maintainer,

dpkg-reconfigure can bring up a dialog that asks which says:
"The interfaces will be automatically detected if this field is left blank."

This is no longer true.

One must find the name in /sys/class/net and enter it in /etc/defaults/isc-dhcp-server or via reconfigure.

From my current  /etc/defaults/isc-dhcp-server config:

# On what interfaces should the DHCP server (dhcpd) serve DHCP requests?
#       Separate multiple interfaces with spaces, e.g. "eth0 eth1".
INTERFACESv4="enp0s31f6"
#INTERFACESv6="enp0s31f6"

( The stock comments here are now obsolete as well )


You can also see that I commented out the IPV6 line which got things working.

The documentation on https://wiki.debian.org/DHCP_Server

needs to be updated as well once this gets resolved.

Might want to put a migration note in /usr/share/doc/isc-dhcp-server re IPv6 and device names while into this.

Dear submitter,

as the package isc-dhcp has just been removed from the Debian archive
unstable we hereby close the associated bug reports.  We are sorry
that we couldn't deal with your issue properly.

For details on the removal, please see https://bugs.debian.org/1143544

The version of this package that was in Debian prior to this removal
can still be found using https://snapshot.debian.org/.

Please note that the changes have been done on the master archive and
will not propagate to any mirrors until the next dinstall run at the
earliest.

This message was generated automatically; if you believe that there is
a problem with it please contact the archive administrators by mailing
ftpmaster@ftp-master.debian.org.

Debian distribution maintenance software
pp.
Thorsten Alteholz (the ftpmaster behind the curtain)