Utiliser dnsmasq comme aiguilleur

etc dnsmasq.d custom

# note que ça peut être /etc/NetworkManager/dnsmasq.d/custom pour utiliser NetworkManager comme aiguilleur.

bind-interfaces
except-interface=docker0
except-interface=virbr*
except-interface=lxcbr*

log-queries
dns-forward-max=5
# 1h de TTL de base
max-ttl=3600
max-cache-ttl=3600
# Ne pas mettre en cache /etc/hosts
local-ttl=0
# En cas de NXDOMAIN, redemander dans les 10s
neg-ttl=10

# Aiguillage
server=/docker/192.168.7.254
server=/lxc/192.168.6.254
server=/lan.novapost.net/10.0.160.254
server=/serenity2.novapost.net/10.0.160.254

etc lxc default.conf

lxc.network.type = veth
lxc.network.link = lxcbr0

lxc.mount.entry = /home/bersace/src usr/local/src none defaults,bind,uid=0,create=dir 0 0

etc lxc dnsmasq.lxcbr0.conf

bind-interfaces
except-interface=lo
dhcp-range=192.168.6.1,192.168.6.200,15m
dns-forward-max=5
domain=lxc
local=/lxc/
log-dhcp
log-queries

etc network interfaces.d dockerports

auto dockerports0
iface dockerports0 inet manual 
        pre-up ip link add $IFACE type dummy
        pre-up ip link set dev $IFACE up
        post-down ip link set dev $IFACE down || true
        post-down ip link delete dev $IFACE type dummy || true

# dnsdock
iface dockerports0 inet static
        netwask 255.255.255.0
        address 192.168.7.254

etc network interfaces.d lxcbr0

# Ne pas oublier dans /etc/network/interfaces : source-directory interfaces.d

auto lxcbr0
iface lxcbr0 inet static
        bridge_ports none
        address 192.168.6.254
        netmask 255.255.255.0
        post-up iptables -A FORWARD -i $IFACE -s 192.168.6.0/24 -j ACCEPT
        post-down iptables -D FORWARD -i $IFACE -s 192.168.6.0/24 -j ACCEPT
        post-up iptables -A POSTROUTING -t nat -s 192.168.6.0/24 ! -d 192.168.6.0/24 -j MASQUERADE
        post-down iptables -D POSTROUTING -t nat -s 192.168.6.0/24 ! -d 192.168.6.0/24 -j MASQUERADE
        post-up iptables -A POSTROUTING -t mangle -p udp --dport bootpc -s 192.168.6.0/24 -j CHECKSUM --checksum-fill
        post-down iptables -D POSTROUTING -t mangle -p udp --dport bootpc -s 192.168.6.0/24 -j CHECKSUM --checksum-fill
        post-up dnsmasq --interface=$IFACE --conf-file=/etc/lxc/dnsmasq.$IFACE.conf --pid-file=/var/run/lxc-dnsmasq.$IFACE.pid
        post-down kill $(cat /var/run/lxc-dnsmasq.$IFACE.pid)

J'ai implémenté ce gist en playbook ansible :

https://github.com/bersace/dotfiles/blob/master/virtualisation.yml

cc @wo0dyn @arkadefr @toopy