summaryrefslogtreecommitdiff
path: root/NEWS
blob: 36546f43810a5cde5ccb49f9d0e27a15fcde60cb (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
Post-v2.0.0
---------------------
   - The default OpenFlow and OVSDB ports will change to
     IANA-assigned numbers in a future release.  Consider updating
     your installations to specify port numbers instead of using the
     defaults.
   - OpenFlow:
     * The OpenFlow 1.1+ "Write-Actions" instruction is now supported.
   - ovs-vswitchd.conf.db.5 man page will contain graphviz/dot
     diagram only if graphviz package was installed at the build time.


v2.0.0 - 15 Oct 2013
---------------------
    - The ovs-vswitchd process is no longer single-threaded.  Multiple
      threads are now used to handle flow set up and asynchronous
      logging.
    - OpenFlow:
      * Experimental support for OpenFlow 1.1 (in addition to 1.2 and
        1.3, which had experimental support in 1.10).
      * Experimental protocol support for OpenFlow 1.1+ groups.  This
        does not yet include an implementation in the Open vSwitch
        software switch.
      * Experimental protocol support for OpenFlow 1.2+ meters.  This
        does not yet include an implementation in the Open vSwitch
        software switch.
      * New support for matching outer source and destination IP address
        of tunneled packets, for tunnel ports configured with the newly
        added "remote_ip=flow" and "local_ip=flow" options.
      * Support for matching on metadata 'pkt_mark' for interacting with
        other system components. On Linux this corresponds to the skb
        mark.
      * Support matching, rewriting SCTP ports
    - The Interface table in the database has a new "ifindex" column to
      report the interface's OS-assigned ifindex.
    - New "check-oftest" Makefile target for running OFTest against Open
      vSwitch.  See README-OFTest for details.
    - The flow eviction threshold has been moved to the Open_vSwitch table.
    - Database names are now mandatory when specifying ovsdb-server options
      through database paths (e.g. Private key option with the database name
      should look like "--private-key=db:Open_vSwitch,SSL,private_key").
    - Added ovs-dev.py, a utility script helpful for Open vSwitch developers.
    - Support for Linux kernels up to 3.10
    - ovs-ofctl:
      * New "ofp-parse" for printing OpenFlow messages read from a file.
      * New commands for OpenFlow 1.1+ groups.
    - Added configurable flow caching support to IPFIX exporter.
    - Dropped support for Linux pre-2.6.32.
    - Log file timestamps and ovsdb commit timestamps are now reported
      with millisecond resolution.  (Previous versions only reported
      whole seconds.)


v1.11.0 - 28 Aug 2013
---------------------
    - Support for megaflows, which allows wildcarding in the kernel (and
      any dpif implementation that supports wildcards).  Depending on
      the flow table and switch configuration, flow set up rates are
      close to the Linux bridge.
    - The "tutorial" directory contains a new tutorial for some advanced
      Open vSwitch features.
    - Stable bond mode has been removed.
    - The autopath action has been removed.
    - New support for the data encapsulation format of the LISP tunnel
      protocol (RFC 6830).  An external control plane or manual flow
      setup is required for EID-to-RLOC mapping.
    - OpenFlow:
      * The "dec_mpls_ttl" and "set_mpls_ttl" actions from OpenFlow
        1.1 and later are now implemented.
      * New "stack" extension for use in actions, to push and pop from
        NXM fields.
      * The "load" and "set_field" actions can now modify the "in_port".  (This
        allows one to enable output to a flow's input port by setting the
        in_port to some unused value, such as OFPP_NONE.)
    - ovs-dpctl:
      * New debugging commands "add-flow", "mod-flow", "del-flow".
      * "dump-flows" now has a -m option to increase output verbosity.
    - In dpif-based bridges, cache action translations, which can improve
      flow set up performance by 80% with a complicated flow table.
    - New syslog format, prefixed with "ovs|", to be easier to filter.
    - RHEL: Removes the default firewall rule that allowed GRE traffic to
      pass through. Any users that relied on this automatic firewall hole
      will have to manually configure it. The ovs-ctl(8) manpage documents
      the "enable-protocol" command that can be used as an alternative.
    - New CFM demand mode which uses data traffic to indicate interface
      liveness.

v1.10.0 - 01 May 2013
---------------------
    - Bridge compatibility support has been removed.  Any uses that
      rely on ovs-brcompatd will have to stick with Open vSwitch 1.9.x
      or adapt to native Open vSwitch support (e.g. use ovs-vsctl instead
      of brctl).
    - The maximum size of the MAC learning table is now configurable.
    - With the Linux datapath, packets for new flows are now queued
      separately on a per-port basis, so it should no longer be
      possible for a large number of new flows arriving on one port to
      prevent new flows from being processed on other ports.
    - ovs-vsctl:
      * Previously ovs-vsctl would retry connecting to the database forever,
        causing it to hang if ovsdb-server was not running.  Now, ovs-vsctl
        only tries once by default (use --retry to try forever).  This change
        means that you may want to remove uses of --timeout to avoid hangs
        in ovs-vsctl calls.
      * Many "ovs-vsctl" database commands now accept an --if-exists option.
        Please refer to the ovs-vsctl manpage for details.
    - OpenFlow:
      - Experimental support for newer versions of OpenFlow.  See
        the "What versions of OpenFlow does Open vSwitch support?"
        question in the FAQ for more details.
      - The OpenFlow "dp_desc" may now be configured by setting the
        value of other-config:dp-desc in the Bridge table.
      - It is possible to request the OpenFlow port number with the
        "ofport_request" column in the Interface table.
      - The NXM flow_removed message now reports the OpenFlow table ID
        from which the flow was removed.
    - Tunneling:
      - New support for the VXLAN tunnel protocol (see the IETF draft here:
        http://tools.ietf.org/html/draft-mahalingam-dutt-dcops-vxlan-03).
      - Tunneling requires the version of the kernel module paired with
        Open vSwitch 1.9.0 or later.
      - Inheritance of the Don't Fragment bit in IP tunnels (df_inherit)
        is no longer supported.
      - Path MTU discovery is no longer supported.
      - CAPWAP tunneling support removed.
      - Tunnels with multicast destination ports are no longer supported.
    - ovs-dpctl:
      - The "dump-flows" and "del-flows" no longer require an argument
        if only one datapath exists.
    - ovs-appctl:
      - New "vlog/disable-rate-limit" and "vlog/enable-rate-limit"
        commands available allow control over logging rate limits.
      - New "dpif/dump-dps", "dpif/show", and "dpif/dump-flows" command
        that mimic the equivalent ovs-dpctl commands.
    - The ofproto library is now responsible for assigning OpenFlow port
      numbers.  An ofproto implementation should assign them when
      port_construct() is called.
    - All dpif-based bridges of a particular type share a common
      datapath called "ovs-<type>", e.g. "ovs-system".  The ovs-dpctl
      commands will now return information on that shared datapath.  To
      get the equivalent bridge-specific information, use the new
      "ovs-appctl dpif/*" commands.
    - Backward-incompatible changes:
      - Earlier Open vSwitch versions treated ANY as a wildcard in flow
        syntax.  OpenFlow 1.1 adds a port named ANY, which introduces a
        conflict.  ANY was rarely used in flow syntax, so we chose to
        retire that meaning of ANY in favor of the OpenFlow 1.1 meaning.
    - Patch ports no longer require kernel support, so they now work
      with FreeBSD and the kernel module built into Linux 3.3 and later.
    - New "sample" action.


v1.9.0 - 26 Feb 2013
------------------------
    - Datapath:
      - Support for ipv6 set action.
      - SKB mark matching and setting.
      - support for Linux kernels up to 3.8
    - FreeBSD is now a supported platform, thanks to code contributions from
      Gaetano Catalli, Ed Maste, and Giuseppe Lettieri.
    - ovs-bugtool: New --ovs option to report only OVS related information.
    - New %t and %T log escapes to identify the subprogram within a
      cooperating group of processes or threads that emitted a log message.
      The default log patterns now include this information.
    - OpenFlow:
      - Allow bitwise masking for SHA and THA fields in ARP, SLL and TLL
        fields in IPv6 neighbor discovery messages, and IPv6 flow label.
      - Adds support for writing to the metadata field for a flow.
    - Tunneling:
      - The tunneling code no longer assumes input and output keys are
        symmetric.  If they are not, PMTUD needs to be disabled for
        tunneling to work. Note this only applies to flow-based keys.
      - New support for a nonstandard form of GRE that supports a 64-bit key.
      - Tunnel Path MTU Discovery default value was set to 'disabled'.
        This feature is deprecated and will be removed soon.
      - Tunnel header caching removed.
    - ovs-ofctl:
      - Commands and actions that accept port numbers now also accept keywords
        that represent those ports (such as LOCAL, NONE, and ALL).  This is
        also the recommended way to specify these ports, for compatibility
        with OpenFlow 1.1 and later (which use the OpenFlow 1.0 numbers
        for these ports for different purposes).
    - ovs-dpctl:
      - Support requesting the port number with the "port_no" option in
        the "add-if" command.
    - ovs-pki: The "online PKI" features have been removed, along with
      the ovs-pki-cgi program that facilitated it, because of some
      alarmist insecurity claims.  We do not believe that these claims
      are true, but because we do not know of any users for this
      feature it seems better on balance to remove it.  (The ovs-pki-cgi
      program was not included in distribution packaging.)
    - ovsdb-server now enforces the immutability of immutable columns.  This
      was not enforced in earlier versions due to an oversight.
    - The following features are now deprecated.  They will be removed no
      earlier than February 2013.  Please email dev@openvswitch.org with
      concerns.
        - Bridge compatibility.
        - Stable bond mode.
        - The autopath action.
        - Interface type "null".
        - Numeric values for reserved ports (see "ovs-ofctl" note above).
        - Tunnel Path MTU Discovery.
        - CAPWAP tunnel support.
    - The data in the RARP packets can now be matched in the same way as the
      data in ARP packets.


v1.8.0 - 26 Feb 2013
------------------------
    *** Internal only release ***
    - New FAQ.  Please send updates and additions!
    - Authors of controllers, please read the new section titled "Action
      Reproduction" in DESIGN, which describes an Open vSwitch change in
      behavior in corner cases that may affect some controllers.
    - ovs-l3ping:
        - A new test utility that can create L3 tunnel between two Open
          vSwitches and detect connectivity issues.
    - ovs-ofctl:
        - New --sort and --rsort options for "dump-flows" command.
        - "mod-port" command can now control all OpenFlow config flags.
    - OpenFlow:
      - Allow general bitwise masking for IPv4 and IPv6 addresses in
        IPv4, IPv6, and ARP packets.  (Previously, only CIDR masks
        were allowed.)
      - Allow support for arbitrary Ethernet masks.  (Previously, only
        the multicast bit in the destination address could be individually
	masked.)
      - New field OXM_OF_METADATA, to align with OpenFlow 1.1.
      - The OFPST_QUEUE request now reports an error if a specified port or
        queue does not exist, or for requests for a specific queue on all
        ports, if the specified queue does not exist on any port.  (Previous
        versions generally reported an empty set of results.)
      - New "flow monitor" feature to allow controllers to be notified of
        flow table changes as they happen.
    - Additional protocols are not mirrored and dropped when forward-bpdu is
      false.  For a full list, see the ovs-vswitchd.conf.db man page.
    - Open vSwitch now sends RARP packets in situations where it previously
      sent a custom protocol, making it consistent with behavior of QEMU and
      VMware.
    - All Open vSwitch programs and log files now show timestamps in UTC,
      instead the local timezone, by default.


v1.7.0 - 30 Jul 2012
------------------------
    - kernel modules are renamed. openvswitch_mod.ko is now
      openvswitch.ko and brcompat_mod.ko is now brcompat.ko.
    - Increased the number of NXM registers to 8.
    - Added ability to configure DSCP setting for manager and controller
      connections.  By default, these connections have a DSCP value of
      Internetwork Control (0xc0).
    - Added the granular link health statistics, 'cfm_health', to an
      interface.
    - OpenFlow:
        - Added support to mask nd_target for ICMPv6 neighbor discovery flows.
        - Added support for OpenFlow 1.3 port description (OFPMP_PORT_DESC)
          multipart messages.
    - ovs-ofctl:
        - Added the "dump-ports-desc" command to retrieve port
          information using the new port description multipart messages.
    - ovs-test:
        - Added support for spawning ovs-test server from the client.
        - Now ovs-test is able to automatically create test bridges and ports.
    - "ovs-dpctl dump-flows" now prints observed TCP flags in TCP flows.
    - Tripled flow setup performance.
    - The "coverage/log" command previously available through ovs-appctl
      has been replaced by "coverage/show".  The new command replies with
      coverage counter values, instead of logging them.


v1.6.1 - 25 Jun 2012
------------------------
    - Allow OFPP_CONTROLLER as the in_port for packet-out messages.


v1.6.0 - 24 Feb 2012
------------------------
    *** Internal only release ***
    - bonding
        - LACP bonds no longer fall back to balance-slb when negotiations fail.
          Instead they drop traffic.
        - The default bond_mode changed from SLB to active-backup, to protect
          unsuspecting users from the significant risks of SLB bonds (which are
          documented in vswitchd/INTERNALS).
        - Load balancing can be disabled by setting the bond-rebalance-interval
          to zero.
    - OpenFlow:
        - Added support for bitwise matching on TCP and UDP ports.
          See ovs-ofctl(8) for more information.
        - NXM flow dumps now include times elapsed toward idle and hard
          timeouts.
        - Added an OpenFlow extension NXT_SET_ASYNC_CONFIG that allows
          controllers more precise control over which OpenFlow messages they
          receive asynchronously.
        - New "fin_timeout" action.
        - Added "fin_timeout" support to "learn" action.
        - New Nicira action NXAST_CONTROLLER that offers additional features
          over output to OFPP_CONTROLLER.
    - When QoS settings for an interface do not configure a default queue
      (queue 0), Open vSwitch now uses a default configuration for that
      queue, instead of dropping all packets as in previous versions.
    - Logging:
        - Logging to console and file will have UTC timestamp as a default for
          all the daemons. An example of the default format is
          2012-01-27T16:35:17Z.  ovs-appctl can be used to change the default
          format as before.
        - The syntax of commands and options to set log levels was simplified,
          to make it easier to remember.
    - New support for limiting the number of flows in an OpenFlow flow
      table, with configurable policy for evicting flows upon
      overflow.  See the Flow_Table table in ovs-vswitch.conf.db(5)
      for more information.
    - New "enable-async-messages" column in the Controller table.  If set to
      false, OpenFlow connections to the controller will initially have all
      asynchronous messages disabled, overriding normal OpenFlow behavior.
    - ofproto-provider interface:
        - "struct rule" has a new member "used" that ofproto implementations
          should maintain by updating with ofproto_rule_update_used().
    - ovsdb-client:
        - The new option --timestamp causes the "monitor" command to print
          a timestamp with every update.
    - CFM module CCM broadcasts can now be tagged with an 802.1p priority.


v1.5.0 - 01 Jun 2012
------------------------
    - OpenFlow:
        - Added support for querying, modifying, and deleting flows
          based on flow cookie when using NXM.
        - Added new NXM_PACKET_IN format.
        - Added new NXAST_DEC_TTL action.
    - ovs-ofctl:
        - Added daemonization support to the monitor and snoop commands.
    - ovs-vsctl:
        - The "find" command supports new set relational operators
          {=}, {!=}, {<}, {>}, {<=}, and {>=}.
    - ovsdb-tool now uses the typical database and schema installation
      directories as defaults.
    - The default MAC learning timeout has been increased from 60 seconds
      to 300 seconds.  The MAC learning timeout is now configurable.


v1.4.0 - 30 Jan 2012
------------------------
    - Compatible with Open vSwitch kernel module included in Linux 3.3.
    - New "VLAN splinters" feature to work around buggy device drivers
      in old Linux versions.  (This feature is deprecated.  When
      broken device drivers are no longer in widespread use, we will
      delete this feature.)  See ovs-vswitchd.conf.db(5) for more
      information.
    - OpenFlow:
       - Added ability to match on IPv6 flow label through NXM.
       - Added ability to match on ECN bits in IPv4 and IPv6 through NXM.
       - Added ability to match on TTL in IPv4 and IPv6 through NXM.
       - Added ability to modify ECN bits in IPv4.
       - Added ability to modify TTL in IPv4.
    - ovs-vswitchd:
       - Don't require the "normal" action to use mirrors.  Traffic will
         now be properly mirrored for any flows, regardless of their
         actions.
       - Track packet and byte statistics sent on mirrors.
       - The sFlow implementation can now usually infer the correct agent
         device instead of having to be told explicitly.
    - ovs-appctl:
      - New "fdb/flush" command to flush bridge's MAC learning table.
    - ovs-test:
      - A new distributed testing tool that allows one to diagnose performance
        and connectivity issues. This tool currently is not included in RH or
        Xen packages.
    - RHEL packaging now supports integration with Red Hat network scripts.
    - bonding:
      - Post 1.4.*, OVS will be changing the default bond mode from balance-slb
        to active-backup.  SLB bonds carry significant risks with them
        (documented vswitchd/INTERNALS) which we want to prevent unsuspecting
        users from running into.  Users are advised to update any scripts or
        configuration which may be negatively impacted by explicitly setting
        the bond mode which they want to use.


v1.3.0 - 09 Dec 2011
------------------------
    - OpenFlow:
      - Added an OpenFlow extension which allows the "output" action to accept
        NXM fields.
      - Added an OpenFlow extension for flexible learning.
      - Bumped number of NXM registers from four to five.
    - ovs-appctl:
      - New "version" command to determine version of running daemon.
      - If no argument is provided for "cfm/show", displays detailed
        information about all interfaces with CFM enabled.
      - If no argument is provided for "lacp/show", displays detailed
        information about all ports with LACP enabled.
    - ovs-dpctl:
      - New "set-if" command to modify a datapath port's configuration.
    - ovs-vswitchd:
      - The software switch now supports 255 OpenFlow tables, instead
        of just one.  By default, only table 0 is consulted, but the
        new NXAST_RESUBMIT_TABLE action can look up in additional
        tables.  Tables 128 and above are reserved for use by the
        switch itself; please use only tables 0 through 127.
      - Add support for 802.1D spanning tree (STP).
    - Fragment handling extensions:
      - New OFPC_FRAG_NX_MATCH fragment handling mode, in which L4
        fields are made available for matching in fragments with
        offset 0.
      - New NXM_NX_IP_FRAG match field for matching IP fragments (usable
        via "ip_frag" in ovs-ofctl).
      - New ovs-ofctl "get-frags" and "set-frags" commands to get and set
        fragment handling policy.
    - CAPWAP tunneling now supports an extension to transport a 64-bit key.
      By default it remains compatible with the old version and other
      standards-based implementations.
    - Flow setups are now processed in a round-robin manner across ports
      to prevent any single client from monopolizing the CPU and conducting
      a denial of service attack.
    - Added support for native VLAN tagging.  A new "vlan_mode"
      parameter can be set for "port". Possible values: "access",
      "trunk", "native-tagged" and "native-untagged".
    - test-openflowd has been removed.  Please use ovs-vswitchd instead.

v1.2.0 - 03 Aug 2011
------------------------
    - New "ofproto" abstraction layer to ease porting to hardware
      switching ASICs.
    - Packaging for Red Hat Enterprise Linux 5.6 and 6.0.
    - Datapath support for Linux kernels up to 3.0.
    - OpenFlow:
      - New "bundle" and "bundle_load" action extensions.
    - Database:
      - Implement table unique constraints.
      - Support cooperative locking between callers.
    - ovs-dpctl:
      - New "-s" option for "show" command prints packet and byte
        counters for each port.
    - ovs-ofctl:
      - New "--readd" option for "replace-flows".
    - ovs-vsctl:
      - New "show" command to print an overview of configuration.
      - New "comment" command to add remark that explains intentions.
    - ovs-brcompatd has been rewritten to fix long-standing bugs.
    - ovs-openflowd has been renamed test-openflowd and moved into the
      tests directory.  Its presence confused too many users.  Please
      use ovs-vswitchd instead.
    - New ovs-benchmark utility to test flow setup performance.
    - A new log level "off" has been added.  Configuring a log facility
      "off" prevents any messages from being logged to it.  Previously,
      "emer" was effectively "off" because no messages were ever logged at
      level "emer".  Now, errors that cause a process to exit are logged
      at "emer" level.
    - "configure" option --with-l26 has been renamed --with-linux, and
      --with-l26-source has been renamed --with-linux-source.  The old
      names will be removed after the next release, so please update
      your scripts.
    - The "-2.6" suffix has been dropped from the datapath/linux-2.6 and
      datapath/linux-2.6/compat-2.6 directories.
    - Feature removals:
      - Dropped support for "tun_id_from_cookie" OpenFlow extension.
           Please use the extensible match extensions instead.
      - Removed the Maintenance_Point and Monitor tables in an effort
        to simplify 802.1ag configuration.
    - Performance and scalability improvements
    - Bug fixes

v1.1.0 - 05 Apr 2011
------------------------
    - Ability to define policies over IPv6
    - LACP
    - 802.1ag CCM
    - Support for extensible match extensions to OpenFlow
    - QoS:
      - Support for HFSC qdisc.
      - Queue used by in-band control can now be configured.
    - Kernel:
      - Kernel<->userspace interface has been reworked and should be
        close to a stable ABI now.
      - "Port group" concept has been dropped.
    - GRE over IPSEC tunnels
    - Bonding:
      - New active backup bonding mode.
      - New L4 hashing support when LACP is enabled.
      - Source MAC hash now includes VLAN field also.
      - miimon support.
    - Greatly improved handling of large flow tables
    - ovs-dpctl:
      - "show" command now prints full vport configuration.
      - "dump-groups" command removed since kernel support for
        port groups was dropped.
    - ovs-vsctl:
      - New commands for working with the new Managers table.
      - "list" command enhanced with new formatting options and --columns
        option.
      - "get" command now accepts new --id option.
      - New "find" command.
    - ovs-ofctl:
      - New "queue-stats" command for printing queue stats.
      - New commands "replace-flows" and "diff-flows".
      - Commands to add and remove flows can now read from files.
      - New --flow-format option to enable or disable NXM.
      - New --more option to increase OpenFlow message verbosity.
      - Removed "tun-cookie" command, which is no longer useful.
    - ovs-controller enhancements for testing various features.
    - New ovs-vlan-test command for testing for Linux kernel driver VLAN
      bugs.  New ovs-vlan-bug-workaround command for enabling and
      disabling a workaround for these driver bugs.
    - OpenFlow support:
      - "Resubmit" actions now update flow statistics.
      - New "register" extension for use in matching and actions, via NXM.
      - New "multipath" experimental action extension.
      - New support for matching multicast Ethernet frames, via NXM.
      - New extension for OpenFlow vendor error codes.
      - New extension to set the QoS output queue without actually
        sending to an output port.
      - Open vSwitch now reports a single flow table, instead of
        separate hash and wildcard tables.  This better models the
        current implementation.
      - New experimental "note" action.
      - New "ofproto/trace" ovs-appctl command and associated utilities
        to ease debugging complex flow tables.
    - Database:
      - Schema documentation now includes an entity-relationship diagram.
      - The database is now garbage collected.  In most tables,
        unreferenced rows will be deleted automatically.
      - Many tables now include statistics updated periodically by
        ovs-vswitchd or ovsdb-server.
      - Every table now has an "external-ids" column for use by OVS
        integrators.
      - There is no default controller anymore.  Each bridge must have its
        controller individually specified.
      - The "fail-mode" is now a property of a Bridge instead of a Controller.
      - New versioning and checksum features.
      - New Managers table and manager_options column in Open_vSwitch table
        for specifying managers.  The old "managers" column in the
        Open_vSwitch table has been removed.
      - Many "name" columns are now immutable.
    - Feature removals:
      - Dropped support for XenServer pre-5.6.100.
      - Dropped support for Linux pre-2.6.18.
      - Dropped controller discovery support.
      - Dropped "ovs-ofctl status" and the OpenFlow extension that it used.
        Statistics reporting in the database is a rough equivalent.
      - Dropped the "corekeeper" package (now separate, at
        http://openvswitch.org/cgi-bin/gitweb.cgi?p=corekeeper).
    - Performance and scalability improvements
    - Bug fixes

v1.1.0pre2 - 13 Sep 2010
------------------------
    - Bug fixes

v1.1.0pre1 - 31 Aug 2010
------------------------
    - OpenFlow 1.0 slicing (QoS) functionality
    - Python bindings for configuration database (no write support)
    - Performance and scalability improvements
    - Bug fixes

v1.0.1 - 31 May 2010
--------------------
    - New "patch" interface type
    - Bug fixes

v1.0.0 - 15 May 2010
--------------------
    - Configuration database with remote management
    - OpenFlow 1.0
    - GRE tunneling
    - Support for XenServer 5.5 and 5.6
    - Performance and scalability improvements
    - Bug fixes

v0.99.2 - 18 Feb 2010
---------------------
    - Bug fixes

v0.99.1 - 25 Jan 2010
---------------------
    - Add support for sFlow(R)
    - Make headers compatible with C++
    - Bug fixes

v0.99.0 - 14 Jan 2010
---------------------
    - User-space forwarding engine
    - Bug fixes

v0.90.7 - 29 Nov 2009
---------------------
    - Add support for NetFlow active timeouts
    - Bug fixes

v0.90.6 - 6 Oct 2009
--------------------
    - Bug fixes

v0.90.5 - 21 Sep 2009
---------------------
    - Generalize in-band control to more diverse network setups
    - Bug fixes