Based on kernel version 4.3. Page generated on 2015-11-02 12:44 EST.
1 Network classifier cgroup 2 ------------------------- 3 4 The Network classifier cgroup provides an interface to 5 tag network packets with a class identifier (classid). 6 7 The Traffic Controller (tc) can be used to assign 8 different priorities to packets from different cgroups. 9 Also, Netfilter (iptables) can use this tag to perform 10 actions on such packets. 11 12 Creating a net_cls cgroups instance creates a net_cls.classid file. 13 This net_cls.classid value is initialized to 0. 14 15 You can write hexadecimal values to net_cls.classid; the format for these 16 values is 0xAAAABBBB; AAAA is the major handle number and BBBB 17 is the minor handle number. 18 Reading net_cls.classid yields a decimal result. 19 20 Example: 21 mkdir /sys/fs/cgroup/net_cls 22 mount -t cgroup -onet_cls net_cls /sys/fs/cgroup/net_cls 23 mkdir /sys/fs/cgroup/net_cls/0 24 echo 0x100001 > /sys/fs/cgroup/net_cls/0/net_cls.classid 25 - setting a 10:1 handle. 26 27 cat /sys/fs/cgroup/net_cls/0/net_cls.classid 28 1048577 29 30 configuring tc: 31 tc qdisc add dev eth0 root handle 10: htb 32 33 tc class add dev eth0 parent 10: classid 10:1 htb rate 40mbit 34 - creating traffic class 10:1 35 36 tc filter add dev eth0 parent 10: protocol ip prio 10 handle 1: cgroup 37 38 configuring iptables, basic example: 39 iptables -A OUTPUT -m cgroup ! --cgroup 0x100001 -j DROP