NEWS

   1 Post-v2.3.0
   2 ---------------------
   3    - The "learn" action supports a new flag "delete_learned" that causes
   4      the learned flows to be deleted when the flow with the "learn" action
   5      is deleted.
   6    - Basic support for the Geneve tunneling protocol. It is not yet
   7      possible to generate or match options. This is planned for a future
   8      release. The protocol is documented at
   9      http://tools.ietf.org/html/draft-gross-geneve-00
  10    - The OVS database now reports controller rate limiting statistics.
  11    - ovs-dpctl functionality is now available for datapaths integrated
  12      into ovs-vswitchd, via ovs-appctl.  Some existing ovs-appctl
  13      commands are now redundant and will be removed in a future
  14      release.  See ovs-vswitchd(8) for details.
  15    - OpenFlow:
  16      * OpenFlow 1.5 (draft) extended registers are now supported.
  17      * OpenFlow 1.5 (draft) Copy-Field action is now supported.
  18      * OpenFlow 1.3+ table features requests are now supported (read-only).
  19      * Nicira extension "move" actions may now be included in action sets.
  20      * "resubmit" actions may now be included in action sets.  The resubmit
  21        is executed last, and only if the action set has no "output" or "group"
  22        action.
  23    - ovs-pki: Changed message digest algorithm from MD5 to SHA-512 because
  24      MD5 is no longer secure and some operating systems have started to disable
  25      it in OpenSSL.
  26    - ovsdb-server: New OVSDB protocol extension allows inequality tests on
  27      "optional scalar" columns.  See ovsdb-server(1) for details.
  28    - test-controller has been renamed ovs-testcontroller at request of users
  29      who find it useful for testing basic OpenFlow setups.  It is still not
  30      a necessary or desirable part of most Open vSwitch deployments.
  31    - Support for travis-ci.org based continuous integration builds has been
  32      added. Build failures are reported to build@openvswitch.org. See INSTALL
  33      file for additional details.
  34    - Experimental support for the Rapid Spanning Tree Protocol
  35      (IEEE 802.1D-2004).  More conformance and interoperability testing is
  36      still needed, so this should not be enabled on production environments.
  37    - Stats are no longer updated on fake bond interface.
  38
  39
  40 v2.3.0 - 14 Aug 2014
  41 ---------------------
  42    - OpenFlow 1.1, 1.2, and 1.3 are now enabled by default in
  43      ovs-vswitchd.
  44    - Linux kernel datapath now has an exact match cache optimizing the
  45      flow matching process.
  46    - Datapath flows now have partially wildcarded tranport port field
  47      matches.  This reduces userspace upcalls, but increases the
  48      number of different masks in the datapath.  The kernel datapath
  49      exact match cache removes the overhead of matching the incoming
  50      packets with the larger number of masks, but when paired with an
  51      older kernel module, some workloads may perform worse with the
  52      new userspace.
  53    - Support for multicast snooping (IGMPv1 and IGMPv2)
  54    - Compatibility with autoconf 2.63 (previously >=2.64)
  55
  56 v2.2.0 - Internal Release
  57 ---------------------
  58    - Internal ports are no longer brought up by default, because it
  59      should be an administrator task to bring up devices as they are
  60      configured properly.
  61    - ovs-vsctl now reports when ovs-vswitchd fails to create a new port or
  62      bridge.
  63    - Port creation and configuration errors are now stored in a new error
  64      column of the Interface table and included in 'ovs-vsctl show'.
  65    - The "ovsdbmonitor" graphical tool has been removed, because it was
  66      poorly maintained and not widely used.
  67    - New "check-ryu" Makefile target for running Ryu tests for OpenFlow
  68      controllers against Open vSwitch.  See INSTALL for details.
  69    - Added IPFIX support for SCTP flows and templates for ICMPv4/v6 flows.
  70    - Upon the receipt of a SIGHUP signal, ovs-vswitchd no longer reopens its
  71      log file (it will terminate instead). Please use 'ovs-appctl vlog/reopen'
  72      instead.
  73    - Support for Linux kernels up to 3.14. From Kernel 3.12 onwards OVS uses
  74      tunnel API for GRE and VXLAN.
  75    - Added DPDK support.
  76    - Added support for custom vlog patterns in Python
  77
  78
  79 v2.1.0 - 19 Mar 2014
  80 ---------------------
  81    - Address prefix tracking support for flow tables.  New columns
  82      "prefixes" in OVS-DB table "Flow_Table" controls which packet
  83      header fields are used for address prefix tracking.  Prefix
  84      tracking allows the classifier to skip rules with longer than
  85      necessary prefixes, resulting in better wildcarding for datapath
  86      flows.  Default configuration is to not use any fields for prefix
  87      tracking.  However, if any flow tables contain both exact matches
  88      and masked matches for IP address fields, OVS performance may be
  89      increased by using this feature.
  90      * As of now, the fields for which prefix lookup can be enabled
  91        are: 'tun_id', 'tun_src', 'tun_dst', 'nw_src', 'nw_dst' (or
  92        aliases 'ip_src' and 'ip_dst'), 'ipv6_src', and 'ipv6_dst'.
  93        (Using this feature for 'tun_id' would only make sense if the
  94        tunnel IDs have prefix structure similar to IP addresses.)
  95      * There is a maximum number of fields that can be enabled for any
  96        one flow table.  Currently this limit is 3.
  97      * Examples:
  98        $ ovs-vsctl set Bridge br0 flow_tables:0=@N1 -- \
  99          --id=@N1 create Flow_Table name=table0
 100        $ ovs-vsctl set Bridge br0 flow_tables:1=@N1 -- \
 101          --id=@N1 create Flow_Table name=table1
 102        $ ovs-vsctl set Flow_Table table0 prefixes=ip_dst,ip_src
 103        $ ovs-vsctl set Flow_Table table1 prefixes=[]
 104    - TCP flags matching: OVS now supports matching of TCP flags.  This
 105      has an adverse performance impact when using OVS userspace 1.10
 106      or older (no megaflows support) together with the new OVS kernel
 107      module.  It is recommended that the kernel and userspace modules
 108      both are upgraded at the same time.
 109    - The default OpenFlow and OVSDB ports will change to
 110      IANA-assigned numbers in a future release.  Consider updating
 111      your installations to specify port numbers instead of using the
 112      defaults.
 113    - OpenFlow:
 114      * The OpenFlow 1.1+ "Write-Actions" instruction is now supported.
 115      * OVS limits the OpenFlow port numbers it assigns to port 32767 and
 116        below, leaving port numbers above that range free for assignment
 117        by the controller.
 118      * ovs-vswitchd now honors changes to the "ofport_request" column
 119        in the Interface table by changing the port's OpenFlow port
 120        number.
 121    - ovs-vswitchd.conf.db.5 man page will contain graphviz/dot
 122      diagram only if graphviz package was installed at the build time.
 123    - Support for Linux kernels up to 3.11
 124    - ovs-dpctl:
 125      The "show" command also displays mega flow mask stats.
 126    - ovs-ofctl:
 127      * New command "ofp-parse-pcap" to dump OpenFlow from PCAP files.
 128    - ovs-controller has been renamed test-controller.  It is no longer
 129      packaged or installed by default, because too many users assumed
 130      incorrectly that ovs-controller was a necessary or desirable part
 131      of an Open vSwitch deployment.
 132    - Added vlog option to export to a UDP syslog sink.
 133    - ovsdb-client:
 134      * The "monitor" command can now monitor all tables in a database,
 135        instead of being limited to a single table.
 136    - The flow-eviction-threshold has been replaced by the flow-limit which is a
 137      hard limit on the number of flows in the datapath.  It defaults to 200,000
 138      flows.  OVS automatically adjusts this number depending on network
 139      conditions.
 140    - Added IPv6 support for active and passive socket communications.
 141
 142
 143 v2.0.0 - 15 Oct 2013
 144 ---------------------
 145     - The ovs-vswitchd process is no longer single-threaded.  Multiple
 146       threads are now used to handle flow set up and asynchronous
 147       logging.
 148     - OpenFlow:
 149       * Experimental support for OpenFlow 1.1 (in addition to 1.2 and
 150         1.3, which had experimental support in 1.10).
 151       * Experimental protocol support for OpenFlow 1.1+ groups.  This
 152         does not yet include an implementation in the Open vSwitch
 153         software switch.
 154       * Experimental protocol support for OpenFlow 1.2+ meters.  This
 155         does not yet include an implementation in the Open vSwitch
 156         software switch.
 157       * New support for matching outer source and destination IP address
 158         of tunneled packets, for tunnel ports configured with the newly
 159         added "remote_ip=flow" and "local_ip=flow" options.
 160       * Support for matching on metadata 'pkt_mark' for interacting with
 161         other system components. On Linux this corresponds to the skb
 162         mark.
 163       * Support matching, rewriting SCTP ports
 164     - The Interface table in the database has a new "ifindex" column to
 165       report the interface's OS-assigned ifindex.
 166     - New "check-oftest" Makefile target for running OFTest against Open
 167       vSwitch.  See README-OFTest for details.
 168     - The flow eviction threshold has been moved to the Open_vSwitch table.
 169     - Database names are now mandatory when specifying ovsdb-server options
 170       through database paths (e.g. Private key option with the database name
 171       should look like "--private-key=db:Open_vSwitch,SSL,private_key").
 172     - Added ovs-dev.py, a utility script helpful for Open vSwitch developers.
 173     - Support for Linux kernels up to 3.10
 174     - ovs-ofctl:
 175       * New "ofp-parse" for printing OpenFlow messages read from a file.
 176       * New commands for OpenFlow 1.1+ groups.
 177     - Added configurable flow caching support to IPFIX exporter.
 178     - Dropped support for Linux pre-2.6.32.
 179     - Log file timestamps and ovsdb commit timestamps are now reported
 180       with millisecond resolution.  (Previous versions only reported
 181       whole seconds.)
 182
 183
 184 v1.11.0 - 28 Aug 2013
 185 ---------------------
 186     - Support for megaflows, which allows wildcarding in the kernel (and
 187       any dpif implementation that supports wildcards).  Depending on
 188       the flow table and switch configuration, flow set up rates are
 189       close to the Linux bridge.
 190     - The "tutorial" directory contains a new tutorial for some advanced
 191       Open vSwitch features.
 192     - Stable bond mode has been removed.
 193     - The autopath action has been removed.
 194     - New support for the data encapsulation format of the LISP tunnel
 195       protocol (RFC 6830).  An external control plane or manual flow
 196       setup is required for EID-to-RLOC mapping.
 197     - OpenFlow:
 198       * The "dec_mpls_ttl" and "set_mpls_ttl" actions from OpenFlow
 199         1.1 and later are now implemented.
 200       * New "stack" extension for use in actions, to push and pop from
 201         NXM fields.
 202       * The "load" and "set_field" actions can now modify the "in_port".  (This
 203         allows one to enable output to a flow's input port by setting the
 204         in_port to some unused value, such as OFPP_NONE.)
 205     - ovs-dpctl:
 206       * New debugging commands "add-flow", "mod-flow", "del-flow".
 207       * "dump-flows" now has a -m option to increase output verbosity.
 208     - In dpif-based bridges, cache action translations, which can improve
 209       flow set up performance by 80% with a complicated flow table.
 210     - New syslog format, prefixed with "ovs|", to be easier to filter.
 211     - RHEL: Removes the default firewall rule that allowed GRE traffic to
 212       pass through. Any users that relied on this automatic firewall hole
 213       will have to manually configure it. The ovs-ctl(8) manpage documents
 214       the "enable-protocol" command that can be used as an alternative.
 215     - New CFM demand mode which uses data traffic to indicate interface
 216       liveness.
 217
 218 v1.10.0 - 01 May 2013
 219 ---------------------
 220     - Bridge compatibility support has been removed.  Any uses that
 221       rely on ovs-brcompatd will have to stick with Open vSwitch 1.9.x
 222       or adapt to native Open vSwitch support (e.g. use ovs-vsctl instead
 223       of brctl).
 224     - The maximum size of the MAC learning table is now configurable.
 225     - With the Linux datapath, packets for new flows are now queued
 226       separately on a per-port basis, so it should no longer be
 227       possible for a large number of new flows arriving on one port to
 228       prevent new flows from being processed on other ports.
 229     - ovs-vsctl:
 230       * Previously ovs-vsctl would retry connecting to the database forever,
 231         causing it to hang if ovsdb-server was not running.  Now, ovs-vsctl
 232         only tries once by default (use --retry to try forever).  This change
 233         means that you may want to remove uses of --timeout to avoid hangs
 234         in ovs-vsctl calls.
 235       * Many "ovs-vsctl" database commands now accept an --if-exists option.
 236         Please refer to the ovs-vsctl manpage for details.
 237     - OpenFlow:
 238       - Experimental support for newer versions of OpenFlow.  See
 239         the "What versions of OpenFlow does Open vSwitch support?"
 240         question in the FAQ for more details.
 241       - The OpenFlow "dp_desc" may now be configured by setting the
 242         value of other-config:dp-desc in the Bridge table.
 243       - It is possible to request the OpenFlow port number with the
 244         "ofport_request" column in the Interface table.
 245       - The NXM flow_removed message now reports the OpenFlow table ID
 246         from which the flow was removed.
 247     - Tunneling:
 248       - New support for the VXLAN tunnel protocol (see the IETF draft here:
 249         http://tools.ietf.org/html/draft-mahalingam-dutt-dcops-vxlan-03).
 250       - Tunneling requires the version of the kernel module paired with
 251         Open vSwitch 1.9.0 or later.
 252       - Inheritance of the Don't Fragment bit in IP tunnels (df_inherit)
 253         is no longer supported.
 254       - Path MTU discovery is no longer supported.
 255       - CAPWAP tunneling support removed.
 256       - Tunnels with multicast destination ports are no longer supported.
 257     - ovs-dpctl:
 258       - The "dump-flows" and "del-flows" no longer require an argument
 259         if only one datapath exists.
 260     - ovs-appctl:
 261       - New "vlog/disable-rate-limit" and "vlog/enable-rate-limit"
 262         commands available allow control over logging rate limits.
 263       - New "dpif/dump-dps", "dpif/show", and "dpif/dump-flows" command
 264         that mimic the equivalent ovs-dpctl commands.
 265     - The ofproto library is now responsible for assigning OpenFlow port
 266       numbers.  An ofproto implementation should assign them when
 267       port_construct() is called.
 268     - All dpif-based bridges of a particular type share a common
 269       datapath called "ovs-<type>", e.g. "ovs-system".  The ovs-dpctl
 270       commands will now return information on that shared datapath.  To
 271       get the equivalent bridge-specific information, use the new
 272       "ovs-appctl dpif/*" commands.
 273     - Backward-incompatible changes:
 274       - Earlier Open vSwitch versions treated ANY as a wildcard in flow
 275         syntax.  OpenFlow 1.1 adds a port named ANY, which introduces a
 276         conflict.  ANY was rarely used in flow syntax, so we chose to
 277         retire that meaning of ANY in favor of the OpenFlow 1.1 meaning.
 278     - Patch ports no longer require kernel support, so they now work
 279       with FreeBSD and the kernel module built into Linux 3.3 and later.
 280     - New "sample" action.
 281
 282
 283 v1.9.0 - 26 Feb 2013
 284 ------------------------
 285     - Datapath:
 286       - Support for ipv6 set action.
 287       - SKB mark matching and setting.
 288       - support for Linux kernels up to 3.8
 289     - FreeBSD is now a supported platform, thanks to code contributions from
 290       Gaetano Catalli, Ed Maste, and Giuseppe Lettieri.
 291     - ovs-bugtool: New --ovs option to report only OVS related information.
 292     - New %t and %T log escapes to identify the subprogram within a
 293       cooperating group of processes or threads that emitted a log message.
 294       The default log patterns now include this information.
 295     - OpenFlow:
 296       - Allow bitwise masking for SHA and THA fields in ARP, SLL and TLL
 297         fields in IPv6 neighbor discovery messages, and IPv6 flow label.
 298       - Adds support for writing to the metadata field for a flow.
 299     - Tunneling:
 300       - The tunneling code no longer assumes input and output keys are
 301         symmetric.  If they are not, PMTUD needs to be disabled for
 302         tunneling to work. Note this only applies to flow-based keys.
 303       - New support for a nonstandard form of GRE that supports a 64-bit key.
 304       - Tunnel Path MTU Discovery default value was set to 'disabled'.
 305         This feature is deprecated and will be removed soon.
 306       - Tunnel header caching removed.
 307     - ovs-ofctl:
 308       - Commands and actions that accept port numbers now also accept keywords
 309         that represent those ports (such as LOCAL, NONE, and ALL).  This is
 310         also the recommended way to specify these ports, for compatibility
 311         with OpenFlow 1.1 and later (which use the OpenFlow 1.0 numbers
 312         for these ports for different purposes).
 313     - ovs-dpctl:
 314       - Support requesting the port number with the "port_no" option in
 315         the "add-if" command.
 316     - ovs-pki: The "online PKI" features have been removed, along with
 317       the ovs-pki-cgi program that facilitated it, because of some
 318       alarmist insecurity claims.  We do not believe that these claims
 319       are true, but because we do not know of any users for this
 320       feature it seems better on balance to remove it.  (The ovs-pki-cgi
 321       program was not included in distribution packaging.)
 322     - ovsdb-server now enforces the immutability of immutable columns.  This
 323       was not enforced in earlier versions due to an oversight.
 324     - The following features are now deprecated.  They will be removed no
 325       earlier than February 2013.  Please email dev@openvswitch.org with
 326       concerns.
 327         - Bridge compatibility.
 328         - Stable bond mode.
 329         - The autopath action.
 330         - Interface type "null".
 331         - Numeric values for reserved ports (see "ovs-ofctl" note above).
 332         - Tunnel Path MTU Discovery.
 333         - CAPWAP tunnel support.
 334     - The data in the RARP packets can now be matched in the same way as the
 335       data in ARP packets.
 336
 337
 338 v1.8.0 - 26 Feb 2013
 339 ------------------------
 340     *** Internal only release ***
 341     - New FAQ.  Please send updates and additions!
 342     - Authors of controllers, please read the new section titled "Action
 343       Reproduction" in DESIGN, which describes an Open vSwitch change in
 344       behavior in corner cases that may affect some controllers.
 345     - ovs-l3ping:
 346         - A new test utility that can create L3 tunnel between two Open
 347           vSwitches and detect connectivity issues.
 348     - ovs-ofctl:
 349         - New --sort and --rsort options for "dump-flows" command.
 350         - "mod-port" command can now control all OpenFlow config flags.
 351     - OpenFlow:
 352       - Allow general bitwise masking for IPv4 and IPv6 addresses in
 353         IPv4, IPv6, and ARP packets.  (Previously, only CIDR masks
 354         were allowed.)
 355       - Allow support for arbitrary Ethernet masks.  (Previously, only
 356         the multicast bit in the destination address could be individually
 357         masked.)
 358       - New field OXM_OF_METADATA, to align with OpenFlow 1.1.
 359       - The OFPST_QUEUE request now reports an error if a specified port or
 360         queue does not exist, or for requests for a specific queue on all
 361         ports, if the specified queue does not exist on any port.  (Previous
 362         versions generally reported an empty set of results.)
 363       - New "flow monitor" feature to allow controllers to be notified of
 364         flow table changes as they happen.
 365     - Additional protocols are not mirrored and dropped when forward-bpdu is
 366       false.  For a full list, see the ovs-vswitchd.conf.db man page.
 367     - Open vSwitch now sends RARP packets in situations where it previously
 368       sent a custom protocol, making it consistent with behavior of QEMU and
 369       VMware.
 370     - All Open vSwitch programs and log files now show timestamps in UTC,
 371       instead the local timezone, by default.
 372
 373
 374 v1.7.0 - 30 Jul 2012
 375 ------------------------
 376     - kernel modules are renamed. openvswitch_mod.ko is now
 377       openvswitch.ko and brcompat_mod.ko is now brcompat.ko.
 378     - Increased the number of NXM registers to 8.
 379     - Added ability to configure DSCP setting for manager and controller
 380       connections.  By default, these connections have a DSCP value of
 381       Internetwork Control (0xc0).
 382     - Added the granular link health statistics, 'cfm_health', to an
 383       interface.
 384     - OpenFlow:
 385         - Added support to mask nd_target for ICMPv6 neighbor discovery flows.
 386         - Added support for OpenFlow 1.3 port description (OFPMP_PORT_DESC)
 387           multipart messages.
 388     - ovs-ofctl:
 389         - Added the "dump-ports-desc" command to retrieve port
 390           information using the new port description multipart messages.
 391     - ovs-test:
 392         - Added support for spawning ovs-test server from the client.
 393         - Now ovs-test is able to automatically create test bridges and ports.
 394     - "ovs-dpctl dump-flows" now prints observed TCP flags in TCP flows.
 395     - Tripled flow setup performance.
 396     - The "coverage/log" command previously available through ovs-appctl
 397       has been replaced by "coverage/show".  The new command replies with
 398       coverage counter values, instead of logging them.
 399
 400
 401 v1.6.1 - 25 Jun 2012
 402 ------------------------
 403     - Allow OFPP_CONTROLLER as the in_port for packet-out messages.
 404
 405
 406 v1.6.0 - 24 Feb 2012
 407 ------------------------
 408     *** Internal only release ***
 409     - bonding
 410         - LACP bonds no longer fall back to balance-slb when negotiations fail.
 411           Instead they drop traffic.
 412         - The default bond_mode changed from SLB to active-backup, to protect
 413           unsuspecting users from the significant risks of SLB bonds (which are
 414           documented in vswitchd/INTERNALS).
 415         - Load balancing can be disabled by setting the bond-rebalance-interval
 416           to zero.
 417     - OpenFlow:
 418         - Added support for bitwise matching on TCP and UDP ports.
 419           See ovs-ofctl(8) for more information.
 420         - NXM flow dumps now include times elapsed toward idle and hard
 421           timeouts.
 422         - Added an OpenFlow extension NXT_SET_ASYNC_CONFIG that allows
 423           controllers more precise control over which OpenFlow messages they
 424           receive asynchronously.
 425         - New "fin_timeout" action.
 426         - Added "fin_timeout" support to "learn" action.
 427         - New Nicira action NXAST_CONTROLLER that offers additional features
 428           over output to OFPP_CONTROLLER.
 429     - When QoS settings for an interface do not configure a default queue
 430       (queue 0), Open vSwitch now uses a default configuration for that
 431       queue, instead of dropping all packets as in previous versions.
 432     - Logging:
 433         - Logging to console and file will have UTC timestamp as a default for
 434           all the daemons. An example of the default format is
 435           2012-01-27T16:35:17Z.  ovs-appctl can be used to change the default
 436           format as before.
 437         - The syntax of commands and options to set log levels was simplified,
 438           to make it easier to remember.
 439     - New support for limiting the number of flows in an OpenFlow flow
 440       table, with configurable policy for evicting flows upon
 441       overflow.  See the Flow_Table table in ovs-vswitch.conf.db(5)
 442       for more information.
 443     - New "enable-async-messages" column in the Controller table.  If set to
 444       false, OpenFlow connections to the controller will initially have all
 445       asynchronous messages disabled, overriding normal OpenFlow behavior.
 446     - ofproto-provider interface:
 447         - "struct rule" has a new member "used" that ofproto implementations
 448           should maintain by updating with ofproto_rule_update_used().
 449     - ovsdb-client:
 450         - The new option --timestamp causes the "monitor" command to print
 451           a timestamp with every update.
 452     - CFM module CCM broadcasts can now be tagged with an 802.1p priority.
 453
 454
 455 v1.5.0 - 01 Jun 2012
 456 ------------------------
 457     - OpenFlow:
 458         - Added support for querying, modifying, and deleting flows
 459           based on flow cookie when using NXM.
 460         - Added new NXM_PACKET_IN format.
 461         - Added new NXAST_DEC_TTL action.
 462     - ovs-ofctl:
 463         - Added daemonization support to the monitor and snoop commands.
 464     - ovs-vsctl:
 465         - The "find" command supports new set relational operators
 466           {=}, {!=}, {<}, {>}, {<=}, and {>=}.
 467     - ovsdb-tool now uses the typical database and schema installation
 468       directories as defaults.
 469     - The default MAC learning timeout has been increased from 60 seconds
 470       to 300 seconds.  The MAC learning timeout is now configurable.
 471
 472
 473 v1.4.0 - 30 Jan 2012
 474 ------------------------
 475     - Compatible with Open vSwitch kernel module included in Linux 3.3.
 476     - New "VLAN splinters" feature to work around buggy device drivers
 477       in old Linux versions.  (This feature is deprecated.  When
 478       broken device drivers are no longer in widespread use, we will
 479       delete this feature.)  See ovs-vswitchd.conf.db(5) for more
 480       information.
 481     - OpenFlow:
 482        - Added ability to match on IPv6 flow label through NXM.
 483        - Added ability to match on ECN bits in IPv4 and IPv6 through NXM.
 484        - Added ability to match on TTL in IPv4 and IPv6 through NXM.
 485        - Added ability to modify ECN bits in IPv4.
 486        - Added ability to modify TTL in IPv4.
 487     - ovs-vswitchd:
 488        - Don't require the "normal" action to use mirrors.  Traffic will
 489          now be properly mirrored for any flows, regardless of their
 490          actions.
 491        - Track packet and byte statistics sent on mirrors.
 492        - The sFlow implementation can now usually infer the correct agent
 493          device instead of having to be told explicitly.
 494     - ovs-appctl:
 495       - New "fdb/flush" command to flush bridge's MAC learning table.
 496     - ovs-test:
 497       - A new distributed testing tool that allows one to diagnose performance
 498         and connectivity issues. This tool currently is not included in RH or
 499         Xen packages.
 500     - RHEL packaging now supports integration with Red Hat network scripts.
 501     - bonding:
 502       - Post 1.4.*, OVS will be changing the default bond mode from balance-slb
 503         to active-backup.  SLB bonds carry significant risks with them
 504         (documented vswitchd/INTERNALS) which we want to prevent unsuspecting
 505         users from running into.  Users are advised to update any scripts or
 506         configuration which may be negatively impacted by explicitly setting
 507         the bond mode which they want to use.
 508
 509
 510 v1.3.0 - 09 Dec 2011
 511 ------------------------
 512     - OpenFlow:
 513       - Added an OpenFlow extension which allows the "output" action to accept
 514         NXM fields.
 515       - Added an OpenFlow extension for flexible learning.
 516       - Bumped number of NXM registers from four to five.
 517     - ovs-appctl:
 518       - New "version" command to determine version of running daemon.
 519       - If no argument is provided for "cfm/show", displays detailed
 520         information about all interfaces with CFM enabled.
 521       - If no argument is provided for "lacp/show", displays detailed
 522         information about all ports with LACP enabled.
 523     - ovs-dpctl:
 524       - New "set-if" command to modify a datapath port's configuration.
 525     - ovs-vswitchd:
 526       - The software switch now supports 255 OpenFlow tables, instead
 527         of just one.  By default, only table 0 is consulted, but the
 528         new NXAST_RESUBMIT_TABLE action can look up in additional
 529         tables.  Tables 128 and above are reserved for use by the
 530         switch itself; please use only tables 0 through 127.
 531       - Add support for 802.1D spanning tree (STP).
 532     - Fragment handling extensions:
 533       - New OFPC_FRAG_NX_MATCH fragment handling mode, in which L4
 534         fields are made available for matching in fragments with
 535         offset 0.
 536       - New NXM_NX_IP_FRAG match field for matching IP fragments (usable
 537         via "ip_frag" in ovs-ofctl).
 538       - New ovs-ofctl "get-frags" and "set-frags" commands to get and set
 539         fragment handling policy.
 540     - CAPWAP tunneling now supports an extension to transport a 64-bit key.
 541       By default it remains compatible with the old version and other
 542       standards-based implementations.
 543     - Flow setups are now processed in a round-robin manner across ports
 544       to prevent any single client from monopolizing the CPU and conducting
 545       a denial of service attack.
 546     - Added support for native VLAN tagging.  A new "vlan_mode"
 547       parameter can be set for "port". Possible values: "access",
 548       "trunk", "native-tagged" and "native-untagged".
 549     - test-openflowd has been removed.  Please use ovs-vswitchd instead.
 550
 551 v1.2.0 - 03 Aug 2011
 552 ------------------------
 553     - New "ofproto" abstraction layer to ease porting to hardware
 554       switching ASICs.
 555     - Packaging for Red Hat Enterprise Linux 5.6 and 6.0.
 556     - Datapath support for Linux kernels up to 3.0.
 557     - OpenFlow:
 558       - New "bundle" and "bundle_load" action extensions.
 559     - Database:
 560       - Implement table unique constraints.
 561       - Support cooperative locking between callers.
 562     - ovs-dpctl:
 563       - New "-s" option for "show" command prints packet and byte
 564         counters for each port.
 565     - ovs-ofctl:
 566       - New "--readd" option for "replace-flows".
 567     - ovs-vsctl:
 568       - New "show" command to print an overview of configuration.
 569       - New "comment" command to add remark that explains intentions.
 570     - ovs-brcompatd has been rewritten to fix long-standing bugs.
 571     - ovs-openflowd has been renamed test-openflowd and moved into the
 572       tests directory.  Its presence confused too many users.  Please
 573       use ovs-vswitchd instead.
 574     - New ovs-benchmark utility to test flow setup performance.
 575     - A new log level "off" has been added.  Configuring a log facility
 576       "off" prevents any messages from being logged to it.  Previously,
 577       "emer" was effectively "off" because no messages were ever logged at
 578       level "emer".  Now, errors that cause a process to exit are logged
 579       at "emer" level.
 580     - "configure" option --with-l26 has been renamed --with-linux, and
 581       --with-l26-source has been renamed --with-linux-source.  The old
 582       names will be removed after the next release, so please update
 583       your scripts.
 584     - The "-2.6" suffix has been dropped from the datapath/linux-2.6 and
 585       datapath/linux-2.6/compat-2.6 directories.
 586     - Feature removals:
 587       - Dropped support for "tun_id_from_cookie" OpenFlow extension.
 588            Please use the extensible match extensions instead.
 589       - Removed the Maintenance_Point and Monitor tables in an effort
 590         to simplify 802.1ag configuration.
 591     - Performance and scalability improvements
 592     - Bug fixes
 593
 594 v1.1.0 - 05 Apr 2011
 595 ------------------------
 596     - Ability to define policies over IPv6
 597     - LACP
 598     - 802.1ag CCM
 599     - Support for extensible match extensions to OpenFlow
 600     - QoS:
 601       - Support for HFSC qdisc.
 602       - Queue used by in-band control can now be configured.
 603     - Kernel:
 604       - Kernel<->userspace interface has been reworked and should be
 605         close to a stable ABI now.
 606       - "Port group" concept has been dropped.
 607     - GRE over IPSEC tunnels
 608     - Bonding:
 609       - New active backup bonding mode.
 610       - New L4 hashing support when LACP is enabled.
 611       - Source MAC hash now includes VLAN field also.
 612       - miimon support.
 613     - Greatly improved handling of large flow tables
 614     - ovs-dpctl:
 615       - "show" command now prints full vport configuration.
 616       - "dump-groups" command removed since kernel support for
 617         port groups was dropped.
 618     - ovs-vsctl:
 619       - New commands for working with the new Managers table.
 620       - "list" command enhanced with new formatting options and --columns
 621         option.
 622       - "get" command now accepts new --id option.
 623       - New "find" command.
 624     - ovs-ofctl:
 625       - New "queue-stats" command for printing queue stats.
 626       - New commands "replace-flows" and "diff-flows".
 627       - Commands to add and remove flows can now read from files.
 628       - New --flow-format option to enable or disable NXM.
 629       - New --more option to increase OpenFlow message verbosity.
 630       - Removed "tun-cookie" command, which is no longer useful.
 631     - ovs-controller enhancements for testing various features.
 632     - New ovs-vlan-test command for testing for Linux kernel driver VLAN
 633       bugs.  New ovs-vlan-bug-workaround command for enabling and
 634       disabling a workaround for these driver bugs.
 635     - OpenFlow support:
 636       - "Resubmit" actions now update flow statistics.
 637       - New "register" extension for use in matching and actions, via NXM.
 638       - New "multipath" experimental action extension.
 639       - New support for matching multicast Ethernet frames, via NXM.
 640       - New extension for OpenFlow vendor error codes.
 641       - New extension to set the QoS output queue without actually
 642         sending to an output port.
 643       - Open vSwitch now reports a single flow table, instead of
 644         separate hash and wildcard tables.  This better models the
 645         current implementation.
 646       - New experimental "note" action.
 647       - New "ofproto/trace" ovs-appctl command and associated utilities
 648         to ease debugging complex flow tables.
 649     - Database:
 650       - Schema documentation now includes an entity-relationship diagram.
 651       - The database is now garbage collected.  In most tables,
 652         unreferenced rows will be deleted automatically.
 653       - Many tables now include statistics updated periodically by
 654         ovs-vswitchd or ovsdb-server.
 655       - Every table now has an "external-ids" column for use by OVS
 656         integrators.
 657       - There is no default controller anymore.  Each bridge must have its
 658         controller individually specified.
 659       - The "fail-mode" is now a property of a Bridge instead of a Controller.
 660       - New versioning and checksum features.
 661       - New Managers table and manager_options column in Open_vSwitch table
 662         for specifying managers.  The old "managers" column in the
 663         Open_vSwitch table has been removed.
 664       - Many "name" columns are now immutable.
 665     - Feature removals:
 666       - Dropped support for XenServer pre-5.6.100.
 667       - Dropped support for Linux pre-2.6.18.
 668       - Dropped controller discovery support.
 669       - Dropped "ovs-ofctl status" and the OpenFlow extension that it used.
 670         Statistics reporting in the database is a rough equivalent.
 671       - Dropped the "corekeeper" package (now separate, at
 672         http://openvswitch.org/cgi-bin/gitweb.cgi?p=corekeeper).
 673     - Performance and scalability improvements
 674     - Bug fixes
 675
 676 v1.1.0pre2 - 13 Sep 2010
 677 ------------------------
 678     - Bug fixes
 679
 680 v1.1.0pre1 - 31 Aug 2010
 681 ------------------------
 682     - OpenFlow 1.0 slicing (QoS) functionality
 683     - Python bindings for configuration database (no write support)
 684     - Performance and scalability improvements
 685     - Bug fixes
 686
 687 v1.0.1 - 31 May 2010
 688 --------------------
 689     - New "patch" interface type
 690     - Bug fixes
 691
 692 v1.0.0 - 15 May 2010
 693 --------------------
 694     - Configuration database with remote management
 695     - OpenFlow 1.0
 696     - GRE tunneling
 697     - Support for XenServer 5.5 and 5.6
 698     - Performance and scalability improvements
 699     - Bug fixes
 700
 701 v0.99.2 - 18 Feb 2010
 702 ---------------------
 703     - Bug fixes
 704
 705 v0.99.1 - 25 Jan 2010
 706 ---------------------
 707     - Add support for sFlow(R)
 708     - Make headers compatible with C++
 709     - Bug fixes
 710
 711 v0.99.0 - 14 Jan 2010
 712 ---------------------
 713     - User-space forwarding engine
 714     - Bug fixes
 715
 716 v0.90.7 - 29 Nov 2009
 717 ---------------------
 718     - Add support for NetFlow active timeouts
 719     - Bug fixes
 720
 721 v0.90.6 - 6 Oct 2009
 722 --------------------
 723     - Bug fixes
 724
 725 v0.90.5 - 21 Sep 2009
 726 ---------------------
 727     - Generalize in-band control to more diverse network setups
 728     - Bug fixes