dummy net driverを使うとLinuxで物理NICを消費せずに仮想ブリッジを作れます。
NICが1つしかない物理マシンでOpenVPNやLXCを使うとき便利♪
続きを書きました!:Linuxでdummy net driverを使った仮想ブリッジを複数作る方法
dummy net driverを使ってdummy0というダミーNICを作ります。
Gentoo Linuxなら /etc/conf.d/net
にこんな感じで書いて、 /etc/init.d/
の下にNIC名でsymlinkを張ります。
# cat /etc/conf.d/net
config_dummy0=(null)
bridge_br0="dummy0"
config_br0="null"
# ls -al /etc/init.d/net.*
lrwxrwxrwx 1 root root 6 Jan 14 05:10 /etc/init.d/net.br0 -> net.lo*
lrwxrwxrwx 1 root root 6 Jan 14 05:13 /etc/init.d/net.dummy0 -> net.lo*
-rwxr-xr-x 1 root root 17412 Dec 5 06:05 /etc/init.d/net.lo*
物理NICを消費せずに仮想ブリッジを起動できました♪
# /etc/init.d/net.br0 start
* Bringing up interface br0
* Creating bridge br0 ...
* Adding ports to br0
* dummy0 ... [ ok ]
* Waiting for IPv6 addresses ... [ ok ]
ifconfig
はこんな感じ。
# ifconfig br0
br0: flags=4419<UP,BROADCAST,RUNNING,PROMISC,MULTICAST> mtu 1500
inet6 fe80::d472:abff:febb:536b prefixlen 64 scopeid 0x20<link>
ether d6:72:ab:bb:53:6b txqueuelen 0 (Ethernet)
RX packets 0 bytes 0 (0.0 B)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 19 bytes 4308 (4.2 KiB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
# ifconfig dummy0
dummy0: flags=195<UP,BROADCAST,RUNNING,NOARP> mtu 1500
inet6 fe80::d472:abff:febb:536b prefixlen 64 scopeid 0x20<link>
ether d6:72:ab:bb:53:6b txqueuelen 0 (Ethernet)
RX packets 0 bytes 0 (0.0 B)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 137 bytes 30835 (30.1 KiB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0