It sounds like that your default inet route is overwritten after dhclient on vlan1 is issued. Did you have a look at the route table before and after each call of dhclient?
> On 13 Jul 2014, at 02:49, Rogier Krieger <rkrie...@gmail.com> wrote: > > Dear list, > > as my ISP is migrating to a new network setup, I'm forced to tinker with my > local setup. Unfortunately, I'm struggling to get two interfaces (vlan0, > vlan1) working simultaneously with DHCP. > > Separately, they work fine. Together, vlan1 drops my internet connection > (vlan0); the latter won't return until I manually re-issue dhclient vlan0. > Upon lease renewal, the same occurs, lest I kill the dhclient instance for > vlan1. > > I wonder if I'm doing something silly. Is the having two simultaneous > dhclient instances a supported setup? The second instance is for an IPTV > set-top-box (STB) that I'd like to keep away from my regular LAN, hence the > routing domains. > > I've disabled PF while trying to get this working, so as to minimise the > amount of things I can do wrong. > > Does anyone have a cluebat for me? Insight greatly appreciated. > > Regards, > > > > Background: > It's a FttH link that provides two tagged networks (vlan 34 for IP; vlan 4 > for IPTV). The latter provides an private range address (in 10.10.12.0/22) > for a set-top-box. > > For the STB: > - IPTV Traffic is to be NATed to vlan4 (towards the 10.10.12.0/22 and > 185.6.48.0/26 ranges) > - Other/Internet traffic (e.g. program guides) needs to travel via the > regular IP uplink (vlan 34) and should be NATed there > > > > # cat /etc/dhclient.conf > supersede host-name "fluor"; > prepend domain-name-servers "27.0.0.1; > > interface "vlan1" { > #ignore routers; # vlan1 is in rdomain 1; default route won't hurt us > } > > > # cat /etc/hostname.em0 > description "internal" > -inet6 > up > > # cat /etc/hostname.em1 > description "uplink" > -inet6 > up > > # cat /etc/hostname.vlan0 > description "ip (uplink)" > vlan 34 vlandev em1 > dhcp > -inet6 > > # cat /etc/hostname.vlan1 > description "tv (uplink)" > rdomain 1 > group tv > vlan 4 vlandev em1 > dhcp > -inet6 > > # cat /etc/hostname.vlan52 > description "tv (downlink) > rdomain 1 > group tv > vlan 52 vlandev em0 > inet 10.0.52.1/24 > -inet6 > > > > > -- > If you don't know where you're going, any road will get you there.