debian/openvswitch-switch.README.Debian

   1 README.Debian for openvswitch-switch
   2 ---------------------------------
   3
   4 To use the Linux kernel-based switch implementation, you will need an
   5 Open vSwitch kernel module.  There are multiple ways to obtain one.
   6 In order of increasing manual effort, these are:
   7
   8        * Use a Linux kernel 3.3 or later, which has an integrated Open
   9          vSwitch kernel module.
  10
  11          The upstream Linux kernel module lacks a few features that
  12          are in the third-party module.  For details, please see the
  13          FAQ, "What features are not available in the Open vSwitch
  14          kernel datapath that ships as part of the upstream Linux
  15          kernel?".
  16
  17        * Install the "openvswitch-datapath-dkms" Debian package that
  18          you built earlier.  This should automatically build and
  19          install the Open vSwitch kernel module for your running
  20          kernel.
  21
  22          This option requires that you have a compiler and toolchain
  23          installed on the machine where you run Open vSwitch, which
  24          may be unacceptable in some production server environments.
  25
  26        * Install the "openvswitch-datapath-source" Debian package, use
  27          "module-assistant" to build a Debian package of the Open
  28          vSwitch kernel module for your kernel, and then install that
  29          Debian package.
  30
  31          You can install the kernel module Debian packages that you
  32          build this way on the same machine where you built it or on
  33          another machine or machines, which means that you don't
  34          necessarily have to have any build infrastructure on the
  35          machines where you use the kernel module.
  36
  37          /usr/share/doc/openvswitch-datapath-source/README.Debian has
  38          details on the build process.
  39
  40        * Build and install the kernel module by hand.
  41
  42
  43 Debian network scripts integration
  44 ----------------------------------
  45 This package lets a user to optionally configure Open vSwitch bridges
  46 and ports from /etc/network/interfaces. Please refer to the interfaces(5)
  47 manpage for more details regarding /etc/network/interfaces.
  48
  49 The stanzas that configure the OVS bridges should begin with "allow-ovs"
  50 followed by name of the bridge. Here is an example.
  51 allow-ovs br0
  52
  53 The stanzas that configure the OVS ports should begin with
  54 "allow-${bridge-name}" followed by name of the port. Here is an example.
  55 allow-br0 eth0
  56
  57 The following OVS specific "command" options are supported:
  58
  59     - ovs_type: This can either be OVSBridge, OVSPort, OVSIntPort, OVSBond,
  60       OVSPatchPort or OVSTunnel depending on whether you configure a bridge,
  61       port, an internal port, a bond, a patch port or a tunnel. This is a
  62       required option.
  63
  64     - ovs_ports: This option specifies all the ports that belong to a bridge.
  65
  66     - ovs_bridge: This options specifies a bridge to which a port belongs.
  67       This is a required option for a port.
  68
  69     - ovs_bonds: This option specifies the list of physical interfaces to be
  70       bonded together.
  71
  72     - ovs_patch_peer: For "OVSPatchPort" interfaces, this field specifies
  73       the patch's peer on the other bridge.
  74
  75     - ovs_tunnel_type: For "OVSTunnel" interfaces, the type of the tunnel.
  76       For example, "gre", "vxlan", etc.
  77
  78     - ovs_tunnel_options: For "OVSTunnel" interfaces, this field should be
  79       used to specify the tunnel options like remote_ip, key, etc.
  80
  81     - ovs_options: This option lets you add extra arguments to a ovs-vsctl
  82       command. See examples.
  83
  84     - ovs_extra: This option lets you run additional ovs-vsctl commands,
  85       separated by "--" (double dash). Variables can be part of the "ovs_extra"
  86       option. You can provide all the standard environmental variables
  87       described in the interfaces(5) man page. You can also pass shell
  88       commands.
  89
  90 More implementation specific details can be seen in the examples.
  91
  92 Examples:
  93 --------
  94 ex 1: A standalone bridge.
  95
  96 allow-ovs br0
  97 iface br0 inet static
  98     address 192.168.1.1
  99     netmask 255.255.255.0
 100     ovs_type OVSBridge
 101
 102 ex 2: A bridge with one port.
 103
 104 allow-ovs br0
 105 iface br0 inet dhcp
 106     ovs_type OVSBridge
 107     ovs_ports eth0
 108
 109 allow-br0 eth0
 110 iface eth0 inet manual
 111     ovs_bridge br0
 112     ovs_type OVSPort
 113
 114 ex 3: A bridge with multiple physical ports.
 115
 116 allow-ovs br0
 117 iface br0 inet dhcp
 118     ovs_type OVSBridge
 119     ovs_ports eth0 eth1
 120
 121 allow-br0 eth0
 122 iface eth0 inet manual
 123     ovs_bridge br0
 124     ovs_type OVSPort
 125
 126 allow-br0 eth1
 127 iface eth1 inet manual
 128     ovs_bridge br0
 129     ovs_type OVSPort
 130
 131 ex 4: A bridge with an OVS internal port.
 132
 133 allow-ovs br1
 134 iface br1 inet static
 135     address 192.168.1.1
 136     netmask 255.255.255.0
 137     ovs_type OVSBridge
 138     ovs_ports vlan100
 139
 140 allow-br1 vlan100
 141 iface vlan100 inet manual
 142     ovs_bridge br1
 143     ovs_type OVSIntPort
 144     ovs_options tag=100
 145     ovs_extra set interface ${IFACE} external-ids:iface-id=$(hostname -s)
 146
 147 ex 5: Bonding.
 148
 149 allow-ovs br2
 150 iface br2 inet static
 151     address 192.170.1.1
 152     netmask 255.255.255.0
 153     ovs_type OVSBridge
 154     ovs_ports bond0
 155
 156 allow-br2 bond0
 157 iface bond0 inet manual
 158     ovs_bridge br2
 159     ovs_type OVSBond
 160     ovs_bonds eth2 eth3
 161     ovs_options bond_mode=balance-tcp lacp=active
 162
 163 ex 6: Patch ports.
 164
 165 allow-ovs br0
 166 iface br0 inet manual
 167     ovs_type OVSBridge
 168     ovs_ports patch0
 169
 170 allow-br0 patch0
 171 iface patch0 inet manual
 172     ovs_bridge br0
 173     ovs_type OVSPatchPort
 174     ovs_patch_peer patch1
 175
 176 allow-ovs br1
 177 iface br1 inet manual
 178     ovs_type OVSBridge
 179     ovs_ports patch1
 180
 181 allow-br1 patch1
 182 iface patch1 inet manual
 183     ovs_bridge br1
 184     ovs_type OVSPatchPort
 185     ovs_patch_peer patch0
 186
 187 ex 7: Tunnel.
 188
 189 allow-ovs br1
 190 iface br1 inet static
 191     address 192.168.1.1
 192     netmask 255.255.255.0
 193     ovs_type OVSBridge
 194     ovs_ports gre1
 195
 196 allow-br1 gre1
 197 iface gre1 inet manual
 198     ovs_bridge br1
 199     ovs_type OVSTunnel
 200     ovs_tunnel_type gre
 201     ovs_tunnel_options options:remote_ip=182.168.1.2 options:key=1
 202
 203 ex 8: Create and destroy bridges.
 204
 205 ifup --allow=ovs $list_of_bridges
 206 ifdown --allow=ovs $list_of_bridges
 207
 208 Notes on dependencies:
 209 ---------------------
 210
 211 openvswitch-switch depends on $network, $named $remote_fs and $syslog to start.
 212 This creates some startup dependency issues.
 213
 214 * Since openvswitch utilities are placed in /usr and /usr can be mounted
 215 through NFS, openvswitch has to start after it.  But if a user uses openvswitch
 216 for all his networking needs and hence to mount NFS, there will be a deadlock.
 217 So, if /usr is mounted through NFS and openvswitch is used for all networking,
 218 the administrator should figure out a way to mount NFS before starting OVS.
 219 One way to do this is in initramfs.
 220
 221 * Since openvswitch starts after $network, $remote_fs and $syslog, any startup
 222 script that depends on openvswitch but starts before it, needs to be changed
 223 to depend on openvswitch-switch too.
 224
 225 * Ideally, an admin should not add openvswitch bridges in the 'auto'
 226 section of the 'interfaces' file.  This is because, when ifupdown starts
 227 working on bridges listed in 'auto', openvswitch has not yet started.
 228
 229 But, if the admin wants to go down this route and adds openvswitch bridges
 230 in the 'auto' section, openvswitch-switch will forcefully be started when
 231 ifupdown kicks in. In a case like this, the admin needs to make sure that /usr
 232 has already been mounted and that a remote $syslog (if used) is ready to
 233 receive openvswitch logs.