IPv6 not working even if enabled in `kathara.conf` and `lab.conf` about kathara

[Skazza94]

Hello @charles2910,
thanks for the issue.

In Kathará, IP stack is not configured by the network plugin. In fact, it creates pure L2 interfaces, so the Layer-3 configuration is up to the user.
First of all, I checked the network scenario that you linked, and you are using the enable_ipv6 metadata that do not exist, hence it is not used.

Before running the scenario, you have to activate the IPv6 stack in using kathara settings, since it is disabled by default. Otherwise, you can set "enable_ipv6": true in the kathara.conf file as you are already doing.
After that, you can set the IPv6 addresses to the interfaces in the <device>.startup files.

I attach you an example lab using both IPv4 and IPv6 addresses.

Do not hesitate to reply if you have further questions.

Mariano.

ipv6_lab.tar.gz

[charles2910]

Hi, Mariano.

Thanks for the reply!

Although I think there must be another configuration missing for me because even your example does not work on my machine (which is running debian 12 Bookworm). The interfaces are indeed created, but I can't ping r1 from c1 using ping6 2100::1 for example.

Is there any additional step I must follow before get IPv6 working in the labs? I do have IPv6 enabled in my machine and also IPv6 forwarding enabled.

P.S.: yes, disable the d*** firewall - I'm using ufw with the default configs and usually it does not block localhost stuff e.g. my VMs which use 192.168.122.0/24 net, but it's blocking only ipv6 packets for some reason, with ipv4 it works out of the box.

Snippet of ip addr while running the lab

157: kt-b61c37016db1: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP group default qlen 1000
    link/ether ae:bb:59:85:6c:74 brd ff:ff:ff:ff:ff:ff
    inet6 fe80::c83f:d2ff:fec8:ecc5/64 scope link 
       valid_lft forever preferred_lft forever
158: kt-6fb92e2e48e2: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP group default qlen 1000
    link/ether de:22:d5:8d:79:61 brd ff:ff:ff:ff:ff:ff
    inet6 fe80::dc22:d5ff:fe8d:7961/64 scope link 
       valid_lft forever preferred_lft forever
159: kt-4a1ac63ce2ef: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP group default qlen 1000
    link/ether 1e:2e:42:13:f6:35 brd ff:ff:ff:ff:ff:ff
    inet6 fe80::1c2e:42ff:fe13:f635/64 scope link 
       valid_lft forever preferred_lft forever
160: vethb47b42dc@if161: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue master kt-4a1ac63ce2ef state UP group default qlen 1000
    link/ether a2:a1:ca:5a:e9:db brd ff:ff:ff:ff:ff:ff link-netnsid 1
    inet6 fe80::a0a1:caff:fe5a:e9db/64 scope link 
       valid_lft forever preferred_lft forever
162: veth7786faf3@if163: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue master kt-6fb92e2e48e2 state UP group default qlen 1000
    link/ether 66:7d:b7:c0:98:e3 brd ff:ff:ff:ff:ff:ff link-netnsid 0
    inet6 fe80::647d:b7ff:fec0:98e3/64 scope link 
       valid_lft forever preferred_lft forever
164: veth55f253b7@if165: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue master kt-b61c37016db1 state UP group default qlen 1000
    link/ether e6:aa:42:7a:7b:f3 brd ff:ff:ff:ff:ff:ff link-netnsid 3
    inet6 fe80::e4aa:42ff:fe7a:7bf3/64 scope link 
       valid_lft forever preferred_lft forever
166: vethe1866c06@if167: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue master kt-6fb92e2e48e2 state UP group default qlen 1000
    link/ether 72:f1:b4:06:14:85 brd ff:ff:ff:ff:ff:ff link-netnsid 2
    inet6 fe80::70f1:b4ff:fe06:1485/64 scope link 
       valid_lft forever preferred_lft forever
168: vethb449446a@if169: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue master kt-b61c37016db1 state UP group default qlen 1000
    link/ether 72:cc:fd:8f:10:13 brd ff:ff:ff:ff:ff:ff link-netnsid 1
    inet6 fe80::70cc:fdff:fe8f:1013/64 scope link 
       valid_lft forever preferred_lft forever
170: veth5da48dbe@if171: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue master kt-4a1ac63ce2ef state UP group default qlen 1000
    link/ether 76:b8:ed:a6:ae:32 brd ff:ff:ff:ff:ff:ff link-netnsid 0
    inet6 fe80::74b8:edff:fea6:ae32/64 scope link 
       valid_lft forever preferred_lft forever

[Skazza94]

Hi @charles2910,
you are right. I also tested the lab and it was not working.
I found out that there was a problem in the network plugin (not correctly installing the iptables rules for IPv6).
I pushed a new version that should solve the problem.

The plugin should update automatically, but it is better if you force a re-installation:

1. Clean all the running Kathará labs:

kathara wipe -f

2. Remove the network plugin:

docker plugin rm -f kathara/katharanp:amd64

or

docker plugin rm -f kathara/katharanp:arm64

depending on your architecture.

3. Relaunch the lab, the plugin will install automatically.

Let me know if you have any other problem!

Mariano.

[charles2910]

Hi, @Skazza94

I've followed your instructions to force a reinstall and I can confirm, it's working now with ufw enabled. Thanks!

A lot of students already downloaded kathara last month, will it update automagically for them? They are going to execute the ipv6 lab next week.

Thanks again!

[Skazza94]

Hi @charles2910,
I tested and unfortunately the plugin is not updated automatically.

We will try to solve it in the next releases (if possible), but it could take a while. I think the best solution is to ask students to run the aforementioned commands to uninstall the plugin.

I am really sorry for the inconvenience, but the APIs to interact with Docker Plugins are really basic (compared to the other set of APIs).

Anyway, I would like to thank you for reporting the bug! 😄

Mariano.