On 18/03/2026 03:32, David Gwynne wrote: > On Tue, Mar 17, 2026 at 08:32:25PM +0100, Kisp??l Zsolt wrote: >> Hello, >> >> I try to configure OpenBSD 7.8 to act as DHCP relay with multiple >> interfaces. >> >> I have the following setup: one Internet facing gateway as well as DHCP >> server (hostname: apu4d4) and an internal router (hostname:alix2c3) >> >> ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? ?? vlan4_192 168.4.254/24 >> ??/ >> ?? ?? ?? ?? ?? ?? ?? +-----------+ ??+------------------+/ >> ?? ?? ?? ?? ?? ?? ?? |?? ?? ?? ?? ?? ??|?? ??192.168.1.0/24?? | | >> INTERNET------+?? APU4D4?? ??+-------------------+vr1?? ALIX2C3 >> ??vr0+----vlan5_192.168.5.126/25 >> ?? ?? ?? ?? ?? ?? ?? |GW&DHCPsrv |.254?? ?? ?? ?? ?? ?? ??.1| Internal >> router?? | >> ?? ?? ?? ?? ?? ?? ?? +-----------+ ??+------------------+\ >> ??\ >> ?? vlan6_192.168.5.254/25 >> >> Config looks like this: >> >> alix2c3$ cat /etc/hostname.vr1 >> media autoselect >> -inet6 >> inet 192.168.1.1 255.255.255.0 192.168.1.255 >> description ===VLAN_1=== >> !route -n add -nostatic -priority 2 default 192.168.1.254 >> up >> >> alix2c3$ cat /etc/hostname.vr0 >> media autoselect >> -inet6 >> -inet >> description ===Virtualization_VLANs=== >> up >> >> alix2c3$ cat /etc/hostname.vlan4 >> inet 192.168.4.254 255.255.255.0 192.168.4.255 parent vr0 vnetid 4 >> description ===Interface_VLAN4=== >> up >> >> alix2c3$ cat /etc/hostname.vlan5 >> inet 192.168.5.126 255.255.255.128 192.168.5.127 parent vr0 vnetid 5 >> description ===Interface_VLAN5=== >> up >> >> alix2c3$ cat /etc/hostname.vlan6 >> inet 192.168.5.254 255.255.255.128 192.168.5.255 parent vr0 vnetid 6 >> description ===Interface_VLAN6=== >> up >> alix2c3$ >> >> I would like to use alix2c3 as DHCP relay for the subnets on vlan4, vlan5 >> and vlan6. I found forum posts where more interfaces was provided to >> dhcrelay but I still get an error message: >> >> alix2c3$ doas dhcrelay -d -i vlan4 -i vlan5 -i vlan6 192.168.1.254 >> usage: dhcrelay [-dor] [-C circuit-id] [-R remote-id] -i interface >> ?? ?? ?? ?? destination ... >> >> Same if I give the interface name instead of the destination DHCP server IP >> >> alix2c3$ doas dhcrelay -d -i vlan4 -i vlan5 -i vlan6 vr1 >> usage: dhcrelay [-dor] [-C circuit-id] [-R remote-id] -i interface >> ?? ?? ?? ?? destination ... >> alix2c3$ >> >> If I give only one interface as then there is no issue. >> >> What do I do wrong? Does OpenBSD dhcrelay support multiple interfaces at >> all? > no, you have a run a dhcrelay per interface. > > cheers, > dlg
This. I make symbolic links in /etc/rc.d/ and run something like that for multiple vlans (with carp) dhcrelay94@ -> /etc/rc.d/dhcrelay rc.conf.local: dhcrelay94_flags=-i carp94 xx.xx.xx.xx yy.yy.yy.yy pkg_scripts=..... dhcrelay93 dhcrelay94 G
