Cilium causes host applications to use IPv6 instead of IPv4

[cilium]

Cilium causes host applications to use IPv6 instead of IPv4

[tgraf]

Was cilium_host the only interface with an IPv6 address on it?

[aanm]

With the scope global yes.

[tgraf]

OK, that explains it. I think we can change the scope to host as packets on that interface never leave the host.

[tgraf]

Can you try

ip addr add $HOST_IP/128 dev $HOST_DEV1 scope host

in bpf/init.sh?

[aanm]

doesn't work, seems like f00d:: is mandatory to be scope global.

sudo ip addr del f00d::c0a8:66:0:ffff/128 dev cilium_host 2> /dev/null || true
sudo ip addr add f00d::c0a8:66:0:ffff/128 dev cilium_host scope host
ip -6 a s cilium_host

52: cilium_host@cilium_net: <BROADCAST,MULTICAST,NOARP,UP,LOWER_UP> mtu 1500 state UP qlen 1000
    inet6 f00d::c0a8:66:0:ffff/128 scope global 
       valid_lft forever preferred_lft forever
    inet6 fe80::a86d:ffff:fe8c:cf/64 scope link 
       valid_lft forever preferred_lft forever

Should we change the f00d prefix?

[tgraf]

Possible solution: use of a site local IPv6 address for the cilium_host