Err, that became too wordy. This is what I wanted to ask:
The common sense way to run a machine is to run it minimalistic, if not else then for sleeping well at night. Now running DHCPD, I like it not to touch any other interface than the dedicated LAN interface - makes general sense, does it not? The only thing that's unique about the LAN interfaces is that among all interfaces, it's the only one to have the unique value pair of its netmask (e.g. 255.255.255.0), and its IPv4 IP (e.g. 1.2.3.4) bitwise-and the netmask (yielding 1.2.3.0). Is that dhcpd's selection criteria for what interfaces to touch, i.e. resolve the IF:s that match netmask and ip-bitwiseand-netmask? ‐‐‐‐‐‐‐ Original Message ‐‐‐‐‐‐‐ On February 28, 2018 12:48 PM, Tinker <t1...@protonmail.ch> wrote: > Hi Marcus, .. > On February 27, 2018 3:41 PM, Marcus MERIGHI mcmer-open...@tor.at wrote: > > > t1...@protonmail.ch (Tinker), 2018.02.27 (Tue) 07:12 (CET): > > > > > Just so I not missed anything in reading the man pages \[1\]: > > > > > > If you have a machine with an external and an internal NIC e.g. em0 and > > > > > > em1 , and you want to serve DHCP only on em1 , then the only way to do > > > > > > that is as a dhcpd argument, e.g. add a line 'dhcpd="em1"' to > > > > > > /etc/rc.conf.local or alternatively add a line "dhcpd em1" to > > > > > > /etc/rc.local - there is no way to specify in /etc/dhcpd.conf which > > > > > > network interfaces dhcpd will bind/serve on, right? > > > > > > Has this been for a particular reason (i.e. it's a feature) or just > > > > > > noone bothered? > > > > > > The usecase I describe above should be typical. > > > > dhcpd(8) reads the subnet declarations from dhcpd.conf(5) and get's to > > > > the interface from there. It does not listen like other network daemons > > > > but uses bpf(4). Try to block it with pf(4)... ;-) > > > > Marcus
