When looking at my Observium monitoring, I just found strange results on this graphs "IPv6 Packet Statistics", this server is on a IPv4 network with IPv6 disabled on the server itself with :
net.ipv6.conf.all.disable_ipv6 = 1
net.ipv6.conf.default.disable_ipv6 = 1
Here is the graph:
When looking on the routes , I still find IPv6 routes (look 6to4) :
ip -6 route show
unreachable ::/96 dev lo metric 1024 error -101 mtu 16436 advmss 16376 hoplimit 4294967295
unreachable ::ffff:0.0.0.0/96 dev lo metric 1024 error -101 mtu 16436 advmss 16376 hoplimit 4294967295
unreachable 2002:a00::/24 dev lo metric 1024 error -101 mtu 16436 advmss 16376 hoplimit 4294967295
unreachable 2002:7f00::/24 dev lo metric 1024 error -101 mtu 16436 advmss 16376 hoplimit 4294967295
unreachable 2002:a9fe::/32 dev lo metric 1024 error -101 mtu 16436 advmss 16376 hoplimit 4294967295
unreachable 2002:ac10::/28 dev lo metric 1024 error -101 mtu 16436 advmss 16376 hoplimit 4294967295
unreachable 2002:c0a8::/32 dev lo metric 1024 error -101 mtu 16436 advmss 16376 hoplimit 4294967295
unreachable 2002:e000::/19 dev lo metric 1024 error -101 mtu 16436 advmss 16376 hoplimit 4294967295
unreachable 3ffe:ffff::/32 dev lo metric 1024 error -101 mtu 16436 advmss 16376 hoplimit 4294967295
fe80::/64 dev eth0 proto kernel metric 256 mtu 1500 advmss 1440 hoplimit 4294967295
fe80::/64 dev eth1 proto kernel metric 256 mtu 1500 advmss 1440 hoplimit 4294967295
fe80::/64 dev eth2 proto kernel metric 256 mtu 1500 advmss 1440 hoplimit 4294967295
Is this normal that I still have IPv6 routes and IPv6 traffic without any IPv6 interface or IPv6 network and IPv6 disabled at Kernel level ? (::1 don't ping)