Install

  1. git clone git://git.openvswitch.org/openvswitch
  2. cd openvswitch
  3. ./boot.sh
  4. ./configure --with-linux=/lib/modules/${uname -r}/build
  5. make
  6. make install
  7. make modules_install
  8. modprobe openvswitch
  9. mkdir -p /usr/local/etc/openvswitch
  10. ovsdb-tool create /usr/local/etc/openvswitch/conf.db vswitchd/vswitch.ovsschema

Startup

  1. ovsdb-server –remote=punix:/usr/local/var/run/openvswitch/db.sock
    –remote=db:Open_vSwitch,Open_vSwitch,manager_options
    –private-key=db:Open_vSwitch,SSL,private_key
    –certificate=db:Open_vSwitch,SSL,certificate
    –bootstrap-ca-cert=db:Open_vSwitch,SSL,ca_cert
    –pidfile –detach
  2. ovs-vsctl --no-wait init
  3. ovs-vswitchd --pidfile --detach

GRE tunnel Configuration

  • Host1
    • ovs-vsctl add-br br1
    • ovs-vsctl add-br br2
    • ovs-vsctl add-port br1 em1
    • ifconfig em1 0;dhclient br1
    • ifconfig br2 10.1.1.1 netmask 255.255.255.0
    • ovs-vsctl add-port br2 gre0 -- set interface gre0 type=gre options:remote_ip=192.168.1.252
  • VM1
    • virsh dumpxml kvm1 > domain.xml
    • search the XML <interface type='network'> section and change it to something like this(see below):
    • virsh create domain.xml
    • ifconfig eth3 up

    • ifconfig eth3 10.1.1.20 netmask 255.255.255.0

        <interface type=&#39;bridge&#39;>
    <mac address=&#39;52:54:00:b8:27:75&#39;/>
    <source bridge=&#39;br2&#39;/>
    <virtualport type=&#39;openvswitch&#39;>
    </virtualport> 
    <model type=&#39;virtio&#39;/> 
    <address type=&#39;pci&#39; domain=&#39;0x0000&#39; bus=&#39;0x00&#39; slot=&#39;0x03&#39; function=&#39;0x0&#39;/> 
  </interface>

      ovs-vsctl show

      390982aa-7bf6-4dfd-84eb-76fe7654e73d Bridge “br2” Port “vnet0” Interface “vnet0” Port “br2” Interface “br2” type: internal Port “gre0” Interface “gre0” type: gre options: {remote_ip=”192.168.1.252”} Bridge “br1” Port “br1” Interface “br1” type: internal Port “em1” Interface “em1”

  • Host2
    • ovs-vsctl add-br br1
    • ovs-vsctl add-br br2
    • ovs-vsctl add-port br1 eth0
    • ifconfig em1 0;dhclient br1
    • ifconfig br2 10.1.1.2 netmask 255.255.255.0
    • ovs-vsctl add-port br2 gre0 -- set interface gre0 type=gre options:remote_ip=192.168.1.249
  • VM2
    • redid the configuration as VM1
    • ifconfig eth5 up

    • ifconfig eth5 10.1.1.30 netmask 255.255.255.0

      ovs-vsctl show

      66f0d773-a7c9-451e-980b-c2def85eda23 Bridge “br1” Port “eth0” Interface “eth0” Port “br1” Interface “br1” type: internal Bridge “br2” Port “gre0” Interface “gre0” type: gre options: {remote_ip=”192.168.1.249”} Port “br2” Interface “br2” type: internal Port “vnet0” Interface “vnet0”

Test

ping VM2 on VM1:

    # ping 10.1.1.30
    PING 10.1.1.30 (10.1.1.30) 56(84) bytes of data.
    64 bytes from 10.1.1.30: icmp_seq=1 ttl=64 time=3.66 ms
    64 bytes from 10.1.1.30: icmp_seq=2 ttl=64 time=1.82 ms
    64 bytes from 10.1.1.30: icmp_seq=3 ttl=64 time=1.47 ms
    64 bytes from 10.1.1.30: icmp_seq=4 ttl=64 time=1.64 ms
    64 bytes from 10.1.1.30: icmp_seq=5 ttl=64 time=1.64 ms

capture the packets on VM2 at the same time:

    # tcpdump -i eth5 -xxx    
    08:24:38.425182 IP 10.1.1.20 > 10.1.1.30: ICMP echo request, id 53255, seq 1, length 64
        0x0000:  5254 001b ead5 5254 00b8 2775 0800 4500
        0x0010:  0054 0000 4000 4001 2476 0a01 0114 0a01
        0x0020:  011e 0800 263f d007 0001 96f1 7852 0000
        0x0030:  0000 2aa1 0900 0000 0000 1011 1213 1415
        0x0040:  1617 1819 1a1b 1c1d 1e1f 2021 2223 2425
        0x0050:  2627 2829 2a2b 2c2d 2e2f 3031 3233 3435
        0x0060:  3637
    08:24:38.425262 IP 10.1.1.30 > 10.1.1.20: ICMP echo reply, id 53255, seq 1, length 64
        0x0000:  5254 00b8 2775 5254 001b ead5 0800 4500
        0x0010:  0054 8ef0 0000 4001 d585 0a01 011e 0a01
        0x0020:  0114 0000 2e3f d007 0001 96f1 7852 0000
        0x0030:  0000 2aa1 0900 0000 0000 1011 1213 1415
        0x0040:  1617 1819 1a1b 1c1d 1e1f 2021 2223 2425
        0x0050:  2627 2829 2a2b 2c2d 2e2f 3031 3233 3435
        0x0060:  3637
    08:24:39.426066 IP 10.1.1.20 > 10.1.1.30: ICMP echo request, id 53255, seq 2, length 64
        0x0000:  5254 001b ead5 5254 00b8 2775 0800 4500
        0x0010:  0054 0000 4000 4001 2476 0a01 0114 0a01
        0x0020:  011e 0800 d835 d007 0002 97f1 7852 0000
        0x0030:  0000 77a9 0900 0000 0000 1011 1213 1415
        0x0040:  1617 1819 1a1b 1c1d 1e1f 2021 2223 2425
        0x0050:  2627 2829 2a2b 2c2d 2e2f 3031 3233 3435
        0x0060:  3637
    08:24:39.426135 IP 10.1.1.30 > 10.1.1.20: ICMP echo reply, id 53255, seq 2, length 64
        0x0000:  5254 00b8 2775 5254 001b ead5 0800 4500
        0x0010:  0054 8ef1 0000 4001 d584 0a01 011e 0a01
        0x0020:  0114 0000 e035 d007 0002 97f1 7852 0000
        0x0030:  0000 77a9 0900 0000 0000 1011 1213 1415
        0x0040:  1617 1819 1a1b 1c1d 1e1f 2021 2223 2425
        0x0050:  2627 2829 2a2b 2c2d 2e2f 3031 3233 3435
        0x0060:  3637

ftrace debug:

  • cd /sys/kernel/debug/tracing
  • echo "iptunnel_xmit" > set_ftrace_filter
  • echo "function_graph" > current_tracer

  • echo "1" > tracing_on

    # cat trace
# tracer: function_graph
#
# CPU  DURATION                  FUNCTION CALLS
# |     |   |                     |   |   |   |
 0) + 63.180 us   |  iptunnel_xmit [openvswitch]();
 0) + 29.963 us   |  iptunnel_xmit [openvswitch]();
 1) + 51.486 us   |  iptunnel_xmit [openvswitch]();
 2) + 49.981 us   |  iptunnel_xmit [openvswitch]();
 ------------------------------------------
 0)  upcall_-1891  =>  vhost-2-2339 
 ------------------------------------------

 0) + 11.770 us   |  iptunnel_xmit [openvswitch]();
 2) + 45.533 us   |  iptunnel_xmit [openvswitch]();
 2) + 48.497 us   |  iptunnel_xmit [openvswitch]();
 2) + 48.216 us   |  iptunnel_xmit [openvswitch]();
 2) + 48.348 us   |  iptunnel_xmit [openvswitch]();

Gre Tunnel 就介绍到这里，之后会简单的介绍下 LISP Tunnel 的配置过程

References

  1. http://wangcong.org/blog/archives/2163
  2. http://networkstatic.net/open-vswitch-gre-tunnel-configuration/