Bug 649530 – net-misc/dhcp-4.3.6_p1 fails to start when network interface has multiple subnets: Interface enp3s0 matches multiple shared networks

• Status: UNCONFIRMED
• Product: Gentoo Linux

[Description Carlos Konstanski 2018-03-04 03:49:52 UTC]

I have dhcpd running on a host with an interface enp3s0 that has multiple subnets:

7: enp3s0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP group default qlen 1000
    link/ether 00:01:2e:6f:ae:af brd ff:ff:ff:ff:ff:ff
    inet 11.96.42.1/24 brd 11.96.42.255 scope global enp3s0
       valid_lft forever preferred_lft forever
    inet 11.96.43.1/24 brd 11.96.43.255 scope global enp3s0
       valid_lft forever preferred_lft forever
    inet 11.96.44.1/24 brd 11.96.44.255 scope global enp3s0
       valid_lft forever preferred_lft forever
    inet6 fe80::201:2eff:fe6f:aeaf/64 scope link 
       valid_lft forever preferred_lft forever

The upgrade to net-misc/dhcp-4.3.6_p1 is now causing this error:

Interface enp3s0 matches multiple shared networks
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exiting.

Reverting to net-misc/dhcp-4.3.5 restores proper behavior.

Nothing in my dhcpd.conf references enp3s0 by name. Everything is in terms of subnets:

subnet 11.96.42.0 netmask 255.255.255.0 {
    range 11.96.42.235 11.96.42.254;
    [options_and_hosts]
}

subnet 11.96.44.0 netmask 255.255.255.0 {
    range 11.96.44.2 11.96.44.254;
    [options_and_hosts]
}