Open vSwitch is an open source virtual switch software that is compatible with the Linux standard bridge. The presentation will provide an overview of Open vSwitch, how to use its basic functions such as setting up bridges and ports, and its data structure that is managed in an ovsdb database.

1. 1
Open vSwitchの使い方とか

2. 2
自己紹介
• 菊田 宏(きくた こう)
• 某社研究開発職
• Twitter : @kotto_hihihi
→ほぼROM
• Open vSwitchを触り始めたキッカケ
→OpenFlowスイッチを探していたら見つけた

3. 3
今日話すこと
• Open vSwitchの概要
• Open vSwitchの基本的な使い方
▫ 各コンポーネントの関係性
• Open vSwitchのデータ構造

4. 4
Open vSwitchとは
• OSSの仮想スイッチ
• Linux標準のbridgeと互換性あり
• 開発者の大半はNicira社の人
• ハードにポーティングすることを意識している

5. 5
Open vSwitchで何ができる？
• 転送機能 ：Bridge, VLAN, STP, LACP, GRE, GRE over IPsec,
CAPWAP
• 管理機能 ：NetFlow, sFlow
• 制御機能 ：OpenFlow1.0, 1.1, 1.2

6. 6
Open vSwitchの歴史？
• 2010/03/15 v1.0.0リリース
▫ OpenFlow1.0.0に対応
▫ GRE対応
→1.0.1まで
• 2011/04/05 v1.1.0リリース
▫ QoS対応
▫ Bonding対応
▫ OpenFlowのベンダ拡張(NXM)対応
→1.1.2まで
• 2011/08/03 v1.2.0リリース
▫ とても性能が良くなったらしい
→1.2.2まで
• 2011/12/09 v1.3.0リリース
▫ FlowTableが255個に(OpenFlow1.1.0の機能が使える？)
▫ STPに対応
▫ NXM機能拡張
• 2012/01/30 v1.4.0リリース
▫ NXM機能拡張
• ※0.9以前のドキュメントが見つけることができませんでした…

7. 7
Open vSwitchインストール
前提：Ubuntu 10.04 server amd64
• パッケージインストール
いろんなところでSSL対応したい場合はlibsslを入れる
# apt-get install make pkg-config gcc autoconf libtool
• Open vSwitchのインストール
# wget http://openvswitch.org/releases/openvswitch-1.4.0.tar.gz
# tar zxvf openvswitch-1.4.0.tar.gz
# cd openvswitch-1.4.0
# ./boot.sh
# ./configure --with-linux=/lib/modules/`uname -r`/build
# make
# make install
# insmod datapath/linux/openvswitch_mod.ko
• ovsdbの作成
# mkdir -p /usr/local/etc/openvswitch
# ovsdb-tool create /usr/local/etc/openvswitch/conf.db ¥
vswitchd/vswitch.ovsschema

8. 8
Open vSwitch起動
• ovsdb-server起動
SSL対応したい場合はlibsslを入れる
# ovsdb-server --remote=punix:/usr/local/var/run/openvswitch/db.sock ¥
--remote=db:Open_vSwitch,manager_options ¥
--pidfile --detach
• vswitchdの起動
# ovs-vsctl --no-wait init
# ovs-vswitchd --pidfile --detach

9. 9
基本的な使い方
• Bridge作成
# ovs-vsctl add-br br0
# ovs-vsctl add-port br0 eth1
# ovs-vsctl add-port br0 eth2
• 設定の確認
# ovs-vsctl list-br
br0
# ovs-vsctl list-ports br0
eth1
br0
eth2
eth1 eth2
10.0.0.1/24 10.0.0.2/24

10. 10
Open vSwitch設定の流れ
① ovs-vsctlコマンドがovsdb-serverに設定情報を送信する
② ovsdb-serverがovs-vswitchdに設定情報を送信する
③ ovs-vswitchdがopenvswitch_modを設定する
④ ovs-vswitchdがovsdb-serverに設定結果を送信する
⑤ ovsdb-serverがovsdbに設定情報、設定結果を登録する
→設定情報は①と②の間に書き込んでいるかもしれない
⑥ ovsdb-serverがovs-vsctlコマンドに設定結果を送信する
設定情報はovsdbで持つ。
ovsdbの実態はovsdb-toolで
ovs-vsctl 作成したconf.dbファイル。
① ⑥
JSON-RPC
②
ovs-vswitchd ovsdb-server ⑤ ovsdb
④
③
openvswitch_mod

11. 11
少し脱線
設定済みのovsdbファイルをコピーすると同じ環境が作れる
ovsdbファイルをコピー
ovsdb-server,
ovsdb ovsdb ovsdb ovsdb ovs-vswitchdを起動
ovsdb-server ovsdb-server ovsdb-server ovsdb-server
コピー元と
ovs-vswitchd ovs-vswitchd ovs-vswitchd ovs-vswitchd 同じ環境になる
br0 br0 br0 br0
eth1 eth2 eth1 eth2 eth1 eth2 eth1 eth2

12. 12
もう少しだけ脱線
ovs-vswitchdとovsdb-server間をTCP/IP or SSLで接続して、複数のOpen
vSwitchホストをovsdb専用ホストで集中管理することもできる
ovsdb ovsdb ovsdb ovsdb ovsdb
専用ホスト ovsdb-server ovsdb-server ovsdb-server ovsdb-server
ovs-vswitchd ovs-vswitchd ovs-vswitchd ovs-vswitchd
Open vSwitch br0 br0 br0 br0
ホスト群
eth1 eth2 eth1 eth2 eth1 eth2 eth1 eth2

13. 13
libvirtとの連携
brctlコマンドを使うことができればよい
• bridge-utilsをインストールする
# apt-get install bridge-utils
• ovs-brcompatdを起動する
# cd openvswitch-1.4.0
# insmod openvswitch-1.4.0/datapath/linux/brcompat_mod.ko
# ovs-brcompatd --pidfile --detach
• brctlコマンドが使えるようになる
# brctl addbr br1
# brctl addif br1 eth1
# brctl addif br1 eth2
• brctlコマンドで設定した結果がovs-vsctlコマンドで確認できる
# ovs-vsctl list-br
br1
# ovs-vsctl list-ports br1
eth1
eth2

14. 14
brctlコマンド利用時の設定の流れ
① brctlコマンドがbrcompat_modを設定する
② brcompat_modがovs-brcompatdに設定情報を通知する
③ ovs-brcompatdがovs-vsctlコマンドを実行する
④ 以降、ovs-vsctlコマンド利用時と同じ
brctl ovs-vsctl
③ ④ ⑨
①
JSON-RPC
⑤
ovs-brcompatd ovs-vswitchd ovsdb-server ⑧ ovsdb
⑦
② ⑥
brcompat_mod openvswitch_mod

15. 15
OpenFlowスイッチとして使う
• 最初からOpenFlowのフローエントリベースで動作している
#ovs-ofctl dump-flows br0
NXST_FLOW reply (xid=0x4):
cookie=0x0, duration=2058.998s, table=0, n_packets=183, n_bytes=29257, priority=0 actions=NORMAL
• フローエントリを削除すると通信できなくなる
#ovs-ofctl del-flows br0
#ovs-ofctl dump-flows br0
NXST_FLOW reply (xid=0x4):

16. 16
OpenFlowスイッチとして使う
• ovs-ofctlコマンドでフローエントリが書ける
# ovs-ofctl add-flow br0 ¥
in_port=1,dl_type=0x0800,nw_src=10.0.0.1,nw_dst=10.0.0.2,actions=output:2
# ovs-ofctl add-flow br0 ¥
in_port=2,dl_type=0x0800,nw_src=10.0.0.2,nw_dst=10.0.0.1,actions=output:1
→フィルタリングにも使える
• フローエントリを書くときに使えるfield
in_port, dl_vlan, dl_vlan_pcp, dl_src, dl_dst, dl_type, nw_src, nw_dst, nw_proto, nw_tos,
nw_ecn, nw_ttl, tp_src, tp_dst, icmp_type, icmp_code, table, vlan_tci, ip_frag, arp_sha,
arp_tha, ipv6_src, ipv6_dst, ipv6_label, nd_target, nd_sll, nd_tll, tun_id, regX
→OpenFlow 1.1, 1.2に9割対応しているらしい

17. 17
ovs-ofctlでフローエントリ設定の流れ
① ovs-ofctlコマンドがovs-vswitchdに設定情報を送信する
② ovs-vswitchdがopenvswitch_modを設定する
brctl ovs-ofctl ovs-vsctl
①
JSON-RPC
ovs-brcompatd ovs-vswitchd ovsdb-server ovsdb
②
brcompat_mod openvswitch_mod

18. 18
コントローラから制御する
• OpenFlowコントローラと接続する
# ovs-vsctl set-controller br0 tcp:172.0.0.10:6633
• OpenFlowコントローラが設定されるとL2SWとして動作するための
フローエントリが消える
# ovs-ofctl dump-flows br0
NXST_FLOW reply (xid=0x4):
→以降、コントローラの制御で動作する。
コントローラ
ovs-vswitchd
br0
eth1 eth2

19. 19
Open vSwitchのデータ構造
ovsdb-clientを使ってovsdbのデータ構造を見る
どんなDBがあるか？ どんなtableがあるか？
# ovsdb-client list-dbs # ovsdb-client list-tables Open_vSwitch
Open_vSwitch Table
------------
Capability
SSL
Bridge
Controller
NetFlow
Port
Mirror
Queue
QoS
Interface
Open_vSwitch
sFlow
Manager

20. 20
Open vSwitchのデータ構造
各tableのcolumnと設定可能な値の定義
# ovsdb-client list-columns Open_vSwitch Bridge
Column Type
------------- ------------------------------------------------------------------------------
status {"key":"string","max":"unlimited","min":0,"value":"string"}
fail_mode {"key":{"enum":["set",["secure","standalone"]],"type":"string"},"min":0}
other_config {"key":"string","max":"unlimited","min":0,"value":"string"}
_version "uuid"
name "string"
datapath_type "string"
netflow {"key":{"refTable":"NetFlow","type":"uuid"},"min":0}
ports {"key":{"refTable":"Port","type":"uuid"},"max":"unlimited","min":0}
external_ids {"key":"string","max":"unlimited","min":0,"value":"string"}
flood_vlans {"key":{"maxInteger":4095,"minInteger":0,"type":"integer"},"max":4096,"min":0}
_uuid "uuid"
controller {"key":{"refTable":"Controller","type":"uuid"},"max":"unlimited","min":0}
datapath_id {"key":"string","min":0}
stp_enable "boolean"
mirrors {"key":{"refTable":"Mirror","type":"uuid"},"max":"unlimited","min":0}
sflow {"key":{"refTable":"sFlow","type":"uuid"},"min":0}

21. 21
Open vSwitchのデータ構造
Open_vSwitch
1 1 1 1
0,* 0,* 0,1 0,*
Manager Capability SSL Bridge
1 1 1 1
1
0,1 0,* 0,* 0,1
NetFlow Mirror Controller sFlow
1
0,* 0,*
Port
1 1 0,1
*
QoS
Interface 1
0,*
Queue

22. 22
Open vSwitchのデータ構造
実際の設定はどうなっているか
ovs-vsctlコマンドで確認
# ovs-vsctl list bridge
_uuid : 333ad8b8-7486-40ab-9d29-5051144734c2
controller : [311d4af1-6d48-4b75-85ed-17e67a94cfb0]
datapath_id : "000000151769d908"
datapath_type : ""
external_ids : {}
fail_mode : []
flood_vlans : []
mirrors : []
name : "br0"
netflow : []
other_config : {}
ports : [65f57564-d408-42ac-84f7-7c6a4b433a5e, 86ecd3a9-7776-4567-83a3-ae19b9e4b46e,
f490bdfa-8424-475a-9949-d10e2d3b8820]
sflow : []
status : {}
stp_enable : false

23. 23
ovsdbに直接設定
ovs-vsctlコマンドでfail_modeにsecureを設定してみる
# ovs-vsctl set Bridge br0 fail_mode=secure
# ovs-vsctl list Bridge
_uuid : 333ad8b8-7486-40ab-9d29-5051144734c2
controller : [34d55998-475b-47d4-aa72-a37cfa6d294a]
datapath_id : "000000151769d908"
datapath_type : ""
external_ids : {}
fail_mode : secure
flood_vlans : []
mirrors : []
name : "br0"
netflow : []
other_config : {}
ports : [65f57564-d408-42ac-84f7-7c6a4b433a5e, 86ecd3a9-7776-4567-83a3-ae19b9e4b46e,
f490bdfa-8424-475a-9949-d10e2d3b8820]
sflow : []
status : {}
stp_enable : false

24. 24
まとめ
• Open vSwitchの基本的な使い方を紹介
• Open vSwitchを構成するコンポーネントの関係性を紹介
• Open vSwitchのデータ構造を紹介

25. 25
(参考)Open_vSwitchテーブル構造
# ovsdb-client list-columns Open_vSwitch Open_vSwitch
Column Type
--------------- ------------------------------------------------------------------------------------------
_uuid "uuid"
system_type {"key":"string","min":0}
external_ids {"key":"string","max":"unlimited","min":0,"value":"string"}
capabilities {"key":"string","max":"unlimited","min":0,"value":{"refTable":"Capability","type":"uuid"}}
system_version {"key":"string","min":0}
_version "uuid"
manager_options {"key":{"refTable":"Manager","type":"uuid"},"max":"unlimited","min":0}
other_config {"key":"string","max":"unlimited","min":0,"value":"string"}
statistics {"key":"string","max":"unlimited","min":0,"value":"string"}
cur_cfg "integer"
ssl {"key":{"refTable":"SSL","type":"uuid"},"min":0}
ovs_version {"key":"string","min":0}
next_cfg "integer"
db_version {"key":"string","min":0}
bridges {"key":{"refTable":"Bridge","type":"uuid"},"max":"unlimited","min":0}

26. 26
(参考)Bridgeテーブル構造
# ovsdb-client list-columns Open_vSwitch Bridge
Column Type
------------- ------------------------------------------------------------------------------
status {"key":"string","max":"unlimited","min":0,"value":"string"}
fail_mode {"key":{"enum":["set",["secure","standalone"]],"type":"string"},"min":0}
other_config {"key":"string","max":"unlimited","min":0,"value":"string"}
_version "uuid"
name "string"
datapath_type "string"
netflow {"key":{"refTable":"NetFlow","type":"uuid"},"min":0}
ports {"key":{"refTable":"Port","type":"uuid"},"max":"unlimited","min":0}
external_ids {"key":"string","max":"unlimited","min":0,"value":"string"}
flood_vlans {"key":{"maxInteger":4095,"minInteger":0,"type":"integer"},"max":4096,"min":0}
_uuid "uuid"
controller {"key":{"refTable":"Controller","type":"uuid"},"max":"unlimited","min":0}
datapath_id {"key":"string","min":0}
stp_enable "boolean"
mirrors {"key":{"refTable":"Mirror","type":"uuid"},"max":"unlimited","min":0}
sflow {"key":{"refTable":"sFlow","type":"uuid"},"min":0}

27. 27
(参考)Portテーブル構造
# ovsdb-client list-columns Open_vSwitch Port
Column Type
--------------- -------------------------------------------------------------------------------------------------------
bond_fake_iface "boolean"
status {"key":"string","max":"unlimited","min":0,"value":"string"}
other_config {"key":"string","max":"unlimited","min":0,"value":"string"}
bond_mode {"key":{"enum":["set",["active-backup","balance-slb","balance-tcp","stable"]],"type":"string"},"min":0}
_version "uuid"
interfaces {"key":{"refTable":"Interface","type":"uuid"},"max":"unlimited"}
name "string"
bond_updelay "integer"
vlan_mode {"key":{"enum":["set",["access","native-tagged","native-untagged","trunk"]],"type":"string"},"min":0}
lacp {"key":{"enum":["set",["active","off","passive"]],"type":"string"},"min":0}
mac {"key":"string","min":0}
_uuid "uuid"
external_ids {"key":"string","max":"unlimited","min":0,"value":"string"}
trunks {"key":{"maxInteger":4095,"minInteger":0,"type":"integer"},"max":4096,"min":0}
statistics {"key":"string","max":"unlimited","min":0,"value":"integer"}
fake_bridge "boolean"
tag {"key":{"maxInteger":4095,"minInteger":0,"type":"integer"},"min":0}
bond_downdelay "integer"
qos {"key":{"refTable":"QoS","type":"uuid"},"min":0}

28. 28
(参考)Interfaceテーブル構造
# ovsdb-client list-columns Open_vSwitch Interface
Column Type
---------------------- ----------------------------------------------------------------
status {"key":"string","max":"unlimited","min":0,"value":"string"}
link_resets {"key":"integer","min":0}
link_speed {"key":"integer","min":0}
duplex {"key":{"enum":["set",["full","half"]],"type":"string"},"min":0}
admin_state {"key":{"enum":["set",["down","up"]],"type":"string"},"min":0}
ofport {"key":"integer","min":0}
_version "uuid"
other_config {"key":"string","max":"unlimited","min":0,"value":"string"}
name "string"
link_state {"key":{"enum":["set",["down","up"]],"type":"string"},"min":0}
type "string"
mtu {"key":"integer","min":0}
mac {"key":"string","min":0}
cfm_mpid {"key":"integer","min":0}
cfm_fault {"key":"boolean","min":0}
_uuid "uuid"
external_ids {"key":"string","max":"unlimited","min":0,"value":"string"}
options {"key":"string","max":"unlimited","min":0,"value":"string"}
ingress_policing_rate {"key":{"minInteger":0,"type":"integer"}}
statistics {"key":"string","max":"unlimited","min":0,"value":"integer"}
cfm_remote_mpids {"key":"integer","max":"unlimited","min":0}
ingress_policing_burst {"key":{"minInteger":0,"type":"integer"}}
lacp_current {"key":"boolean","min":0}

29. 29
(参考)QoSテーブル構造
# ovsdb-client list-columns Open_vSwitch QoS
Column Type
------------ ---------------------------------------------------------------------------------------------------------------
-----------------------
queues
{"key":{"maxInteger":4294967295,"minInteger":0,"type":"integer"},"max":"unlimited","min":0,"value":{
"refTable":"Queue","type":"uuid"}}
external_ids {"key":"string","max":"unlimited","min":0,"value":"string"}
_uuid "uuid"
type "string"
other_config {"key":"string","max":"unlimited","min":0,"value":"string"}
_version "uuid"

30. 30
(参考)Queueテーブル構造
# ovsdb-client list-columns Open_vSwitch Queue
Column Type
------------ -----------------------------------------------------------------
external_ids {"key":"string","max":"unlimited","min":0,"value":"string"}
_uuid "uuid"
dscp {"key":{"maxInteger":63,"minInteger":0,"type":"integer"},"min":0}
other_config {"key":"string","max":"unlimited","min":0,"value":"string"}
_version "uuid"

31. 31
(参考)Controllerテーブル構造
# ovsdb-client list-columns Open_vSwitch Controller
Column Type
---------------------- ---------------------------------------------------------------------------
_uuid "uuid"
external_ids {"key":"string","max":"unlimited","min":0,"value":"string"}
status {"key":"string","max":"unlimited","min":0,"value":"string"}
local_netmask {"key":"string","min":0}
_version "uuid"
is_connected "boolean"
controller_burst_limit {"key":{"minInteger":25,"type":"integer"},"min":0}
max_backoff {"key":{"minInteger":1000,"type":"integer"},"min":0}
controller_rate_limit {"key":{"minInteger":100,"type":"integer"},"min":0}
local_ip {"key":"string","min":0}
local_gateway {"key":"string","min":0}
connection_mode {"key":{"enum":["set",["in-band","out-of-band"]],"type":"string"},"min":0}
inactivity_probe {"key":"integer","min":0}
target "string"
role {"key":{"enum":["set",["master","other","slave"]],"type":"string"},"min":0}

32. 32
(参考)Managerテーブル構造
# ovsdb-client list-columns Open_vSwitch Manager
Column Type
---------------- --------------------------------------------------------------------------
_uuid "uuid"
external_ids {"key":"string","max":"unlimited","min":0,"value":"string"}
status {"key":"string","max":"unlimited","min":0,"value":"string"}
max_backoff {"key":{"minInteger":1000,"type":"integer"},"min":0}
_version "uuid"
is_connected "boolean"
connection_mode {"key":{"enum":["set",["in-band","out-of-band"]],"type":"string"},"min":0}
inactivity_probe {"key":"integer","min":0}
target "string"

33. 33
(参考)Capabilityテーブル構造
# ovsdb-client list-columns Open_vSwitch Capability
Column Type
-------- -----------------------------------------------------------
_uuid "uuid"
details {"key":"string","max":"unlimited","min":0,"value":"string"}
_version "uuid"

34. 34
(参考)SSLテーブル構造
# ovsdb-client list-columns Open_vSwitch SSL
Column Type
----------------- -----------------------------------------------------------
certificate "string"
external_ids {"key":"string","max":"unlimited","min":0,"value":"string"}
_uuid "uuid"
private_key "string"
ca_cert "string"
bootstrap_ca_cert "boolean"
_version "uuid"

35. 35
(参考)Mirrorテーブル構造
# ovsdb-client list-columns Open_vSwitch Mirror
Column Type
--------------- ------------------------------------------------------------------------------------
_uuid "uuid"
external_ids {"key":"string","max":"unlimited","min":0,"value":"string"}
select_vlan {"key":{"maxInteger":4095,"minInteger":0,"type":"integer"},"max":4096,"min":0}
select_src_port {"key":{"refTable":"Port","refType":"weak","type":"uuid"},"max":"unlimited","min":0}
_version "uuid"
select_all "boolean"
name "string"
statistics {"key":"string","max":"unlimited","min":0,"value":"integer"}
select_dst_port {"key":{"refTable":"Port","refType":"weak","type":"uuid"},"max":"unlimited","min":0}
output_port {"key":{"refTable":"Port","refType":"weak","type":"uuid"},"min":0}
output_vlan {"key":{"maxInteger":4095,"minInteger":1,"type":"integer"},"min":0}

36. 36
(参考)NetFlowテーブル構造
# ovsdb-client list-columns Open_vSwitch NetFlow
Column Type
------------------- ------------------------------------------------------------------
_uuid "uuid"
external_ids {"key":"string","max":"unlimited","min":0,"value":"string"}
targets {"key":"string","max":"unlimited"}
add_id_to_interface "boolean"
_version "uuid"
active_timeout {"key":{"minInteger":-1,"type":"integer"}}
engine_id {"key":{"maxInteger":255,"minInteger":0,"type":"integer"},"min":0}
engine_type {"key":{"maxInteger":255,"minInteger":0,"type":"integer"},"min":0}

37. 37
(参考)sFlowテーブル構造
# ovsdb-client list-columns Open_vSwitch sFlow
Column Type
------------ -----------------------------------------------------------
_uuid "uuid"
external_ids {"key":"string","max":"unlimited","min":0,"value":"string"}
targets {"key":"string","max":"unlimited"}
agent {"key":"string","min":0}
header {"key":"integer","min":0}
_version "uuid"
sampling {"key":"integer","min":0}
polling {"key":"integer","min":0}