Compose: ipv6_address broken

[peterthomassen]

I am using docker 1.12.1 on Ubuntu 16.04, and docker-compose 1.8.1. The Compose file from https://docs.docker.com/compose/compose-file/#ipv4-address-ipv6-address does not run correctly: The ipv6_address setting seems to be ignored. I tried on various machines.

For reference, I created docker-compose.yml with the following content:

version: '2'

services:
  app:
    image: busybox
    command: ifconfig
    networks:
      app_net:
        ipv4_address: 172.16.238.10
        ipv6_address: 2001:3984:3989::10

networks:
  app_net:
    driver: bridge
    driver_opts:
      com.docker.network.enable_ipv6: "true"
    ipam:
      driver: default
      config:
      - subnet: 172.16.238.0/24
        gateway: 172.16.238.1
      - subnet: 2001:3984:3989::/64
        gateway: 2001:3984:3989::1

Now, running docker-compose up produces

Creating network "tmp_app_net" with driver "bridge"
Creating tmp_app_1
Attaching to tmp_app_1
app_1  | eth0      Link encap:Ethernet  HWaddr 02:42:AC:10:EE:0A  
app_1  |           inet addr:172.16.238.10  Bcast:0.0.0.0  Mask:255.255.255.0
app_1  |           inet6 addr: fe80::42:acff:fe10:ee0a/64 Scope:Link
app_1  |           UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
app_1  |           RX packets:4 errors:0 dropped:0 overruns:0 frame:0
app_1  |           TX packets:1 errors:0 dropped:0 overruns:0 carrier:0
app_1  |           collisions:0 txqueuelen:0 
app_1  |           RX bytes:520 (520.0 B)  TX bytes:90 (90.0 B)
app_1  | 
app_1  | lo        Link encap:Local Loopback  
app_1  |           inet addr:127.0.0.1  Mask:255.0.0.0
app_1  |           inet6 addr: ::1/128 Scope:Host
app_1  |           UP LOOPBACK RUNNING  MTU:65536  Metric:1
app_1  |           RX packets:0 errors:0 dropped:0 overruns:0 frame:0
app_1  |           TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
app_1  |           collisions:0 txqueuelen:1 
app_1  |           RX bytes:0 (0.0 B)  TX bytes:0 (0.0 B)
app_1  | 
tmp_app_1 exited with code 0

The IPv6 address is not assigned. That seems to be a bug, either in ipv6_address itself, or there is some required configuration step missing from the documentation.

For further information, here's what I already tried:

1. Starting the docker daemon with --ipv6
2. Starting the docker daemon with --ipv6 --fixed-cidr-v6="2001:3984:3989::/64"
   
   
   
   • Note that docker run -it busybox ifconfig actually gives me an IPv6 address here (from the --fixed-cidr subnet which is assigned to the default bridge network)
   
   
3. Using my actual IPv6 subnet instead of the one from the code example, and repeating 2. with this subnet

[shin-]

I suppose this is related to #3430

[f-andrey]

IPv6 and docker need ip6tables rules and ip -6 neigh add proxy if you planing local access (another host you network)

about such

-A FORWARD -i eth0 -j DOCKER-PUB
-A FORWARD -j DOCKER-ISOLATION
-A FORWARD -o docker0 -j ACCEPT
-A FORWARD -o docker0 -m conntrack --ctstate RELATED,ESTABLISHED -j ACCEPT
-A FORWARD -i docker0 ! -o docker0 -j ACCEPT
-A FORWARD -i docker0 -o docker0 -j ACCEPT
-A DOCKER-ISOLATION -j RETURN

with each container

ip -6 neigh add proxy 2001:3984:3989::10 dev eno1

note that IPv6 containers will be available globally

[peterthomassen]

@f-andrey iptables etc. has nothing to do with the missing _assignment_ of the IPv6 address, right?

[f-andrey]

Sorry, my distraction, did not pay attention docker-compose

I still decided not to deal with the automatic creation of the network and create them manually. And used as external

docker network create --subnet=172.16.238.0/24 --gateway=172.16.238.1 --ipv6 --subnet=2001:3984:3989::/64 -o "com.docker.network.bridge.enable_icc"="true" -o "com.docker.network.bridge.enable_ip_masquerade"="false" -o "com.docker.network.bridge.host_binding_ipv4"="0.0.0.0" -o "com.docker.network.bridge.name"="docker1" -o "com.docker.network.driver.mtu"="1500" app_net

[shin-]

3994

[peterthomassen]

@f-andrey Thanks, this is a suitable workaround. I ended up using docker network create --subnet=172.16.2.0/24 --gateway=172.16.2.1 --ipv6 --subnet=<myV6Network/subnet> -o "com.docker.network.bridge.enable_ip_masquerade"="true" dockerbridge

[peterthomassen]

@shin- #3994 was merged for 1.9.0, and also appears in the change log. However, the result of running docker-compose up with the above Dockerfile (which is still the same in the docs!) is unchanged, i.e. the IPv6 address is missing, despite the fix.

I thought your fix addresses this issue. Can you elaborate? Thanks!

[shin-]

@peterthomassen Sorry for the confusion. You will need to add enable_ipv6 in your network definition going forward. I'll look into getting the documentation updated.

version: '2.1'

services:
  app:
    image: busybox
    command: ifconfig
    networks:
      app_net:
        ipv4_address: 172.16.238.10
        ipv6_address: 2001:3984:3989::10

networks:
  app_net:
    enable_ipv6: true
    driver: bridge
    ipam:
      driver: default
      config:
      - subnet: 172.16.238.0/24
        gateway: 172.16.238.1
      - subnet: 2001:3984:3989::/64
        gateway: 2001:3984:3989::1

Edit: Must also use version 2.1 for support of the new flag.

[shin-]

With the docs change merged, I'll go ahead and close this. Let me know if you're still encountering issues.

[akomakom]

Although "enable_ipv6: true" does work in docker-compose file version 2.1, it does not work in 3.x
Any advice regarding enabling IPv6 in current versions?

   ERROR: The Compose file './docker-compose.yml' is invalid because:
   networks.app_net value Additional properties are not allowed ('enable_ipv6' was unexpected)

[valentin2105]

I'm also blocked with compose 2.1 for IPv6, any idea how to solve this ?

[shoonoise]

@akomakom @valentin2105
try to:

networks:
  app_net:
    driver: bridge
    driver_opts:
      com.docker.network.enable_ipv6: "true"
    ipam:
      driver: default
      config:
      - subnet: 172.16.238.0/24
        gateway: 172.16.238.1
      - subnet: 2001:3984:3989::/64
        gateway: 2001:3984:3989::1

[valentin2105]

@shoonoise With Version '3.2' :
bash-4.3# ip -6 addr bash-4.3#
Not any IPv6 ..