Linux tc Traffic Shaping for IPv6

bandwidth-controlipv6linuxtraffic-shaping

I have traffic shaping with tc and htb in place and everything works fine for IPv4.
Now I want to limit the bandwidth for incoming IPv6 ssh/sftp traffic to some reasonable amount, so it doesn't interfere with more critical traffic.
In short, nothing worked:

tc class add dev eth0 parent 1:0 classid 1:14 htb rate 3000kbit ceil 3000kbit prio 3

ip6tables -A POSTROUTING -t mangle -o eth0 -p tcp --dport 22 -j MARK --set-mark 14
tc filter add dev eth0 parent 1:0 protocol ip handle 14 fw flowid 1:14
# or
tc filter add dev eth0 parent 1:0 protocol ipv6 u32 match ip6 protocol 6 0xff match ip6 dport 22 0xffff flowid 1:14
# or variations of these...

How does one traffic-shape IPv6 data with tc?

Best Answer

At least on my modem/router (Actiontec C1000A, BusyBox v1.17.2, kernel version 2.6.30), I was able to match directly on the destination IPv6 address using tc (i.e. no need for ip6tables to mark the packets):

tc class add dev eth0 parent 1:0 classid 1:14 htb rate 3000kbit ceil 3000kbit prio 3
tc filter add dev eth0 parent 1:0 protocol ipv6 prio 16 \
    u32 match ip6 dst $IPV6_ADDR flowid 1:14

So, it's a guess, but I should think the following would work:

tc filter add dev eth0 parent 1:0 protocol ipv6 prio 16 u32 match ip6 dport 80 flowid 1:14

Or, using your ip6tables mangling:

tc filter add dev eth0 parent 1:0 protocol ipv6 handle 14 fw flowid 1:14
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