場景：
創建一個Virtual Switch,支持VLAN，支持MAC-Learning
包含下面四個Port：
- P1, truck port
- P2, VLAN 20
- P3, P4 VLAN 30
包含五個flow table:
Table 0: Admission control.
Table 1: VLAN input processing.
Table 2: Learn source MAC and VLAN for ingress port.
Table 3: Look up learned port for destination MAC and VLAN.
Table 4: Output processing
首先創建一個bridge
sudo ovs-vsctl add-br helloworld -- set bridge helloworld fail-mode=secure
然后我們查看這個bridge
$ sudo ovs-vsctl show
c24322e6-8453-402a-afaf-64757ef231e9
Bridge helloworld
fail_mode: secure
Port helloworld
Interface helloworld
type: internal
ovs_version: "2.0.1"
$ sudo ovs-ofctl show helloworld
OFPT_FEATURES_REPLY (xid=0x2): dpid:00003ad44a48c646
n_tables:254, n_buffers:256
capabilities: FLOW_STATS TABLE_STATS PORT_STATS QUEUE_STATS ARP_MATCH_IP
actions: OUTPUT SET_VLAN_VID SET_VLAN_PCP STRIP_VLAN SET_DL_SRC SET_DL_DST SET_NW_SRC SET_NW_DST SET_NW_TOS SET_TP_SRC SET_TP_DST ENQUEUE
LOCAL(helloworld): addr:3a:d4:4a:48:c6:46
config: 0
state: 0
speed: 0 Mbps now, 0 Mbps max
OFPT_GET_CONFIG_REPLY (xid=0x4): frags=normal miss_send_len=0
$ sudo ovs-ofctl dump-flows helloworld
NXST_FLOW reply (xid=0x4):
如果設為fail-secure mode，則初始情況下flow table是空的，否則會有normal
$ sudo ovs-vsctl add-br helloworld1
$ sudo ovs-ofctl show helloworld1
OFPT_FEATURES_REPLY (xid=0x2): dpid:00008a2f1d184941
n_tables:254, n_buffers:256
capabilities: FLOW_STATS TABLE_STATS PORT_STATS QUEUE_STATS ARP_MATCH_IP
actions: OUTPUT SET_VLAN_VID SET_VLAN_PCP STRIP_VLAN SET_DL_SRC SET_DL_DST SET_NW_SRC SET_NW_DST SET_NW_TOS SET_TP_SRC SET_TP_DST ENQUEUE
LOCAL(helloworld1): addr:8a:2f:1d:18:49:41
config: 0
state: 0
speed: 0 Mbps now, 0 Mbps max
OFPT_GET_CONFIG_REPLY (xid=0x4): frags=normal miss_send_len=0
$ sudo ovs-ofctl dump-flows helloworld1
NXST_FLOW reply (xid=0x4):
cookie=0x0, duration=31.467s, table=0, n_packets=8, n_bytes=648, idle_age=21, priority=0 actions=NORMAL
接下來，創建四個veth pair
sudo ip link add first_br type veth peer name first_if
sudo ip link add second_br type veth peer name second_if
sudo ip link add third_br type veth peer name third_if
sudo ip link add forth_br type veth peer name forth_if
xxx_br將是添加到bridge上的。
我們添加四個端口port
sudo ovs-vsctl add-port helloworld first_br -- set Interface first_br ofport_request=1
sudo ovs-vsctl add-port helloworld second_br -- set Interface second_br ofport_request=2
sudo ovs-vsctl add-port helloworld third_br -- set Interface third_br ofport_request=3
sudo ovs-vsctl add-port helloworld forth_br -- set Interface forth_br ofport_request=4
ofport_request是指定端口號
新添加的port都是出於DOWN的狀態
$ ip addr
22: first_if: <BROADCAST,MULTICAST> mtu 1500 qdisc noop state DOWN group default qlen 1000
link/ether ca:d4:fd:47:a6:ce brd ff:ff:ff:ff:ff:ff
23: first_br: <BROADCAST,MULTICAST> mtu 1500 qdisc noop master ovs-system state DOWN group default qlen 1000
link/ether f2:ac:70:72:49:61 brd ff:ff:ff:ff:ff:ff
24: second_if: <BROADCAST,MULTICAST> mtu 1500 qdisc noop state DOWN group default qlen 1000
link/ether 76:fa:16:61:d7:0e brd ff:ff:ff:ff:ff:ff
25: second_br: <BROADCAST,MULTICAST> mtu 1500 qdisc noop master ovs-system state DOWN group default qlen 1000
link/ether 66:63:74:a9:0e:f2 brd ff:ff:ff:ff:ff:ff
26: third_if: <BROADCAST,MULTICAST> mtu 1500 qdisc noop state DOWN group default qlen 1000
link/ether 1e:6c:0e:6f:8c:cb brd ff:ff:ff:ff:ff:ff
27: third_br: <BROADCAST,MULTICAST> mtu 1500 qdisc noop master ovs-system state DOWN group default qlen 1000
link/ether 7e:4e:87:28:33:93 brd ff:ff:ff:ff:ff:ff
28: forth_if: <BROADCAST,MULTICAST> mtu 1500 qdisc noop state DOWN group default qlen 1000
link/ether 9a:0d:44:fc:6b:51 brd ff:ff:ff:ff:ff:ff
29: forth_br: <BROADCAST,MULTICAST> mtu 1500 qdisc noop master ovs-system state DOWN group default qlen 1000
link/ether ea:01:d1:6a:2a:07 brd ff:ff:ff:ff:ff:ff
30: helloworld: <BROADCAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UNKNOWN group default
link/ether ee:04:95:bd:a3:4b brd ff:ff:ff:ff:ff:ff
inet6 fe80::b42d:a4ff:fe49:ba75/64 scope link
valid_lft forever preferred_lft forever
$ sudo ovs-ofctl show helloworld
OFPT_FEATURES_REPLY (xid=0x2): dpid:0000ee0495bda34b
n_tables:254, n_buffers:256
capabilities: FLOW_STATS TABLE_STATS PORT_STATS QUEUE_STATS ARP_MATCH_IP
actions: OUTPUT SET_VLAN_VID SET_VLAN_PCP STRIP_VLAN SET_DL_SRC SET_DL_DST SET_NW_SRC SET_NW_DST SET_NW_TOS SET_TP_SRC SET_TP_DST ENQUEUE
1(first_br): addr:f2:ac:70:72:49:61
config: PORT_DOWN
state: LINK_DOWN
current: 10GB-FD COPPER
speed: 10000 Mbps now, 0 Mbps max
2(second_br): addr:66:63:74:a9:0e:f2
config: PORT_DOWN
state: LINK_DOWN
current: 10GB-FD COPPER
speed: 10000 Mbps now, 0 Mbps max
3(third_br): addr:7e:4e:87:28:33:93
config: PORT_DOWN
state: LINK_DOWN
current: 10GB-FD COPPER
speed: 10000 Mbps now, 0 Mbps max
4(forth_br): addr:ea:01:d1:6a:2a:07
config: PORT_DOWN
state: LINK_DOWN
current: 10GB-FD COPPER
speed: 10000 Mbps now, 0 Mbps max
LOCAL(helloworld): addr:ee:04:95:bd:a3:4b
config: 0
state: 0
speed: 0 Mbps now, 0 Mbps max
OFPT_GET_CONFIG_REPLY (xid=0x4): frags=normal miss_send_len=0
把它們設為UP
sudo ip link set first_if up
sudo ip link set first_br up
sudo ip link set second_br up
sudo ip link set second_if up
sudo ip link set third_if up
sudo ip link set third_br up
sudo ip link set forth_br up
sudo ip link set forth_if up
也可以用下面的命令
ovs-ofctl mod-port helloworld first_br up
$ sudo ip addr
22: first_if: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP group default qlen 1000
link/ether ca:d4:fd:47:a6:ce brd ff:ff:ff:ff:ff:ff
inet6 fe80::c8d4:fdff:fe47:a6ce/64 scope link
valid_lft forever preferred_lft forever
23: first_br: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast master ovs-system state UP group default qlen 1000
link/ether f2:ac:70:72:49:61 brd ff:ff:ff:ff:ff:ff
inet6 fe80::f0ac:70ff:fe72:4961/64 scope link
valid_lft forever preferred_lft forever
24: second_if: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP group default qlen 1000
link/ether 76:fa:16:61:d7:0e brd ff:ff:ff:ff:ff:ff
inet6 fe80::74fa:16ff:fe61:d70e/64 scope link
valid_lft forever preferred_lft forever
25: second_br: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast master ovs-system state UP group default qlen 1000
link/ether 66:63:74:a9:0e:f2 brd ff:ff:ff:ff:ff:ff
inet6 fe80::6463:74ff:fea9:ef2/64 scope link
valid_lft forever preferred_lft forever
26: third_if: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP group default qlen 1000
link/ether 1e:6c:0e:6f:8c:cb brd ff:ff:ff:ff:ff:ff
inet6 fe80::1c6c:eff:fe6f:8ccb/64 scope link
valid_lft forever preferred_lft forever
27: third_br: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast master ovs-system state UP group default qlen 1000
link/ether 7e:4e:87:28:33:93 brd ff:ff:ff:ff:ff:ff
inet6 fe80::7c4e:87ff:fe28:3393/64 scope link
valid_lft forever preferred_lft forever
28: forth_if: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP group default qlen 1000
link/ether 9a:0d:44:fc:6b:51 brd ff:ff:ff:ff:ff:ff
inet6 fe80::980d:44ff:fefc:6b51/64 scope link
valid_lft forever preferred_lft forever
29: forth_br: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast master ovs-system state UP group default qlen 1000
link/ether ea:01:d1:6a:2a:07 brd ff:ff:ff:ff:ff:ff
inet6 fe80::e801:d1ff:fe6a:2a07/64 scope link
valid_lft forever preferred_lft forever
30: helloworld: <BROADCAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UNKNOWN group default
link/ether ee:04:95:bd:a3:4b brd ff:ff:ff:ff:ff:ff
inet6 fe80::b42d:a4ff:fe49:ba75/64 scope link
valid_lft forever preferred_lft forever
$ sudo ovs-ofctl show helloworld
OFPT_FEATURES_REPLY (xid=0x2): dpid:0000ee0495bda34b
n_tables:254, n_buffers:256
capabilities: FLOW_STATS TABLE_STATS PORT_STATS QUEUE_STATS ARP_MATCH_IP
actions: OUTPUT SET_VLAN_VID SET_VLAN_PCP STRIP_VLAN SET_DL_SRC SET_DL_DST SET_NW_SRC SET_NW_DST SET_NW_TOS SET_TP_SRC SET_TP_DST ENQUEUE
1(first_br): addr:f2:ac:70:72:49:61
config: 0
state: 0
current: 10GB-FD COPPER
speed: 10000 Mbps now, 0 Mbps max
2(second_br): addr:66:63:74:a9:0e:f2
config: 0
state: 0
current: 10GB-FD COPPER
speed: 10000 Mbps now, 0 Mbps max
3(third_br): addr:7e:4e:87:28:33:93
config: 0
state: 0
current: 10GB-FD COPPER
speed: 10000 Mbps now, 0 Mbps max
4(forth_br): addr:ea:01:d1:6a:2a:07
config: 0
state: 0
current: 10GB-FD COPPER
speed: 10000 Mbps now, 0 Mbps max
LOCAL(helloworld): addr:ee:04:95:bd:a3:4b
config: 0
state: 0
speed: 0 Mbps now, 0 Mbps max
OFPT_GET_CONFIG_REPLY (xid=0x4): frags=normal miss_send_len=0
實現第一個Table 0，Admission control
包進入vswitch的時候首先進入Table 0，我們在這里可以設定規則，控制那些包可以進入，那些包不可以進入。
比如，如果source address是multicast的就不允許進入。
01:00:00:00:00:00/01:00:00:00:00:00是廣播地址
00:00:00:00:00:00/01:00:00:00:00:00是單播地址
這種表示形式類似CIDR
於是我們添加下面的規則：
sudo ovs-ofctl add-flow helloworld "table=0, dl_src=01:00:00:00:00:00/01:00:00:00:00:00, actions=drop"
STP的也不接受
sudo ovs-ofctl add-flow helloworld "table=0, dl_dst=01:80:c2:00:00:00/ff:ff:ff:ff:ff:f0, actions=drop"
我們在添加最后一個flow，這個flow的priority低於default，如果上面兩個不匹配，則我們進入table 1
sudo ovs-ofctl add-flow helloworld "table=0, priority=0, actions=resubmit(,1)"
我們查看一下所有的flow
$ sudo ovs-ofctl dump-flows helloworld
NXST_FLOW reply (xid=0x4):
cookie=0x0, duration=42.162s, table=0, n_packets=0, n_bytes=0, idle_age=42, priority=0 actions=resubmit(,1)
cookie=0x0, duration=232.121s, table=0, n_packets=0, n_bytes=0, idle_age=232, dl_src=01:00:00:00:00:00/01:00:00:00:00:00 actions=drop
cookie=0x0, duration=167.636s, table=0, n_packets=0, n_bytes=0, idle_age=167, dl_dst=01:80:c2:00:00:00/ff:ff:ff:ff:ff:f0 actions=drop
測試Table 0
有個很好的工具ovs-appctl ofproto/trace
不滿足條件DROP
$ sudo ovs-appctl ofproto/trace helloworld in_port=1,dl_dst=01:80:c2:00:00:05
Flow: metadata=0,in_port=1,vlan_tci=0x0000,dl_src=00:00:00:00:00:00,dl_dst=01:80:c2:00:00:05,dl_type=0x0000
Rule: table=0 cookie=0 dl_dst=01:80:c2:00:00:00/ff:ff:ff:ff:ff:f0
OpenFlow actions=drop
Final flow: unchanged
Relevant fields: skb_priority=0,in_port=1,dl_src=00:00:00:00:00:00/01:00:00:00:00:00,dl_dst=01:80:c2:00:00:00/ff:ff:ff:ff:ff:f0,dl_type=0x0000,nw_frag=no
Datapath actions: drop
滿足條件RESUBMIT
$ sudo ovs-appctl ofproto/trace helloworld in_port=1,dl_dst=01:80:c2:00:00:10
Flow: metadata=0,in_port=1,vlan_tci=0x0000,dl_src=00:00:00:00:00:00,dl_dst=01:80:c2:00:00:10,dl_type=0x0000
Rule: table=0 cookie=0 priority=0
OpenFlow actions=resubmit(,1)
Resubmitted flow: unchanged
Resubmitted regs: reg0=0x0 reg1=0x0 reg2=0x0 reg3=0x0 reg4=0x0 reg5=0x0 reg6=0x0 reg7=0x0
Resubmitted odp: drop
No match
Final flow: unchanged
Relevant fields: skb_priority=0,in_port=1,dl_src=00:00:00:00:00:00/01:00:00:00:00:00,dl_dst=01:80:c2:00:00:10/ff:ff:ff:ff:ff:f0,dl_type=0x0000,nw_frag=no
Datapath actions: drop
實現第二個Table 1：VLAN Input Processing
首先添加一個最低優先級的DROP的規則
sudo ovs-ofctl add-flow helloworld "table=1, priority=0, actions=drop"
對於port 1，是trunk口，無論有沒有VLAN Header都接受。
sudo ovs-ofctl add-flow helloworld "table=1, priority=99, in_port=1, actions=resubmit(,2)"
對於port 2, 3, 4, 我們希望沒有VLAN Tag，然后我們給打上VLAN Tag
$ sudo ovs-ofctl add-flows helloworld - <<'EOF'
table=1, priority=99, in_port=2, vlan_tci=0, actions=mod_vlan_vid:20, resubmit(,2)
table=1, priority=99, in_port=3, vlan_tci=0, actions=mod_vlan_vid:30, resubmit(,2)
table=1, priority=99, in_port=4, vlan_tci=0, actions=mod_vlan_vid:30, resubmit(,2)
EOF
$ sudo ovs-ofctl dump-flows helloworld
NXST_FLOW reply (xid=0x4):
cookie=0x0, duration=4478.582s, table=0, n_packets=0, n_bytes=0, idle_age=4478, priority=0 actions=resubmit(,1)
cookie=0x0, duration=4668.541s, table=0, n_packets=0, n_bytes=0, idle_age=4668, dl_src=01:00:00:00:00:00/01:00:00:00:00:00 actions=drop
cookie=0x0, duration=4604.056s, table=0, n_packets=0, n_bytes=0, idle_age=4604, dl_dst=01:80:c2:00:00:00/ff:ff:ff:ff:ff:f0 actions=drop
cookie=0x0, duration=89.273s, table=1, n_packets=0, n_bytes=0, idle_age=89, priority=99,in_port=2,vlan_tci=0x0000 actions=mod_vlan_vid:20,resubmit(,2)
cookie=0x0, duration=89.273s, table=1, n_packets=0, n_bytes=0, idle_age=89, priority=99,in_port=4,vlan_tci=0x0000 actions=mod_vlan_vid:30,resubmit(,2)
cookie=0x0, duration=89.273s, table=1, n_packets=0, n_bytes=0, idle_age=89, priority=99,in_port=3,vlan_tci=0x0000 actions=mod_vlan_vid:30,resubmit(,2)
cookie=0x0, duration=220.318s, table=1, n_packets=0, n_bytes=0, idle_age=220, priority=99,in_port=1 actions=resubmit(,2)
cookie=0x0, duration=298.739s, table=1, n_packets=0, n_bytes=0, idle_age=298, priority=0 actions=drop
測試一個從port 1進入，tag為5的
$ sudo ovs-appctl ofproto/trace helloworld in_port=1,vlan_tci=5
Flow: metadata=0,in_port=1,vlan_tci=0x0005,dl_src=00:00:00:00:00:00,dl_dst=00:00:00:00:00:00,dl_type=0x0000
Rule: table=0 cookie=0 priority=0
OpenFlow actions=resubmit(,1)
Resubmitted flow: unchanged
Resubmitted regs: reg0=0x0 reg1=0x0 reg2=0x0 reg3=0x0 reg4=0x0 reg5=0x0 reg6=0x0 reg7=0x0
Resubmitted odp: drop
Rule: table=1 cookie=0 priority=99,in_port=1
OpenFlow actions=resubmit(,2)
Resubmitted flow: unchanged
Resubmitted regs: reg0=0x0 reg1=0x0 reg2=0x0 reg3=0x0 reg4=0x0 reg5=0x0 reg6=0x0 reg7=0x0
Resubmitted odp: drop
No match
Final flow: unchanged
Relevant fields: skb_priority=0,in_port=1,dl_src=00:00:00:00:00:00/01:00:00:00:00:00,dl_dst=00:00:00:00:00:00/ff:ff:ff:ff:ff:f0,dl_type=0x0000,nw_frag=no
Datapath actions: drop
測試二，從port 2進入，沒有打Tag的
$ sudo ovs-appctl ofproto/trace helloworld in_port=2
Flow: metadata=0,in_port=2,vlan_tci=0x0000,dl_src=00:00:00:00:00:00,dl_dst=00:00:00:00:00:00,dl_type=0x0000
Rule: table=0 cookie=0 priority=0
OpenFlow actions=resubmit(,1)
Resubmitted flow: unchanged
Resubmitted regs: reg0=0x0 reg1=0x0 reg2=0x0 reg3=0x0 reg4=0x0 reg5=0x0 reg6=0x0 reg7=0x0
Resubmitted odp: drop
Rule: table=1 cookie=0 priority=99,in_port=2,vlan_tci=0x0000
OpenFlow actions=mod_vlan_vid:20,resubmit(,2)
Resubmitted flow: metadata=0,in_port=2,dl_vlan=20這里被打上了Tag,dl_vlan_pcp=0,dl_src=00:00:00:00:00:00,dl_dst=00:00:00:00:00:00,dl_type=0x0000
Resubmitted regs: reg0=0x0 reg1=0x0 reg2=0x0 reg3=0x0 reg4=0x0 reg5=0x0 reg6=0x0 reg7=0x0
Resubmitted odp: drop
No match
Final flow: unchanged
Relevant fields: skb_priority=0,in_port=2,vlan_tci=0x0000,dl_src=00:00:00:00:00:00/01:00:00:00:00:00,dl_dst=00:00:00:00:00:00/ff:ff:ff:ff:ff:f0,dl_type=0x0000,nw_frag=no
Datapath actions: drop
測試三：從port進入，帶Tag 5的
$ sudo ovs-appctl ofproto/trace helloworld in_port=2,vlan_tci=5
Flow: metadata=0,in_port=2,vlan_tci=0x0005,dl_src=00:00:00:00:00:00,dl_dst=00:00:00:00:00:00,dl_type=0x0000
Rule: table=0 cookie=0 priority=0
OpenFlow actions=resubmit(,1)
Resubmitted flow: unchanged
Resubmitted regs: reg0=0x0 reg1=0x0 reg2=0x0 reg3=0x0 reg4=0x0 reg5=0x0 reg6=0x0 reg7=0x0
Resubmitted odp: drop
Rule: table=1 cookie=0 priority=0
OpenFlow actions=drop
Final flow: unchanged
Relevant fields: skb_priority=0,in_port=2,vlan_tci=0x0005,dl_src=00:00:00:00:00:00/01:00:00:00:00:00,dl_dst=00:00:00:00:00:00/ff:ff:ff:ff:ff:f0,dl_type=0x0000,nw_frag=no
Datapath actions: drop
實現第三個Table 2: MAC, VLAN learning for ingress port
對於普通的switch，都會有這個學習的過程，當一個包到來的時候，由於包里面有MAC，VLAN Tag，以及從哪個口進來的這個信息。於是switch學習后，維護了一個表格port –> MAC –> VLAN Tag。
這樣以后如果有需要發給這個MAC的包，不用ARP，switch自然之道應該發給哪個port，應該打什么VLAN Tag。
OVS也要學習這個，並維護三個之間的mapping關系。
在我們的例子中，無論是從port進來的本身就帶Tag的，還是從port 2, 3, 4進來的后來被打上Tag的，都需要學習。
sudo ovs-ofctl add-flow helloworld "table=2 actions=learn(table=10, NXM_OF_VLAN_TCI[0..11], NXM_OF_ETH_DST[]=NXM_OF_ETH_SRC[], load:NXM_OF_IN_PORT[]->NXM_NX_REG0[0..15]), resubmit(,3)"
這一句比較難理解。
learn表示這是一個學習的action
table 10，這是一個MAC learning table，學習的結果會放在這個table中。
NXM_OF_VLAN_TCI這個是VLAN Tag，在MAC Learning table中，每一個entry都是僅僅對某一個VLAN來說的，不同VLAN的learning table是分開的。在學習的結果的entry中，會標出這個entry是對於哪個VLAN的。
NXM_OF_ETH_DST[]=NXM_OF_ETH_SRC[]這個的意思是當前包里面的MAC Source Address會被放在學習結果的entry里面的dl_dst里面。這是因為每個switch都是通過Ingress包來學習，某個MAC從某個port進來，switch就應該記住以后發往這個MAC的包要從這個port出去，因而MAC source address就被放在了Mac destination address里面，因為這是為發送用的。
NXM_OF_IN_PORT[]->NXM_NX_REG0將portf放入register.
一般對於學習的entry還需要有hard_timeout，這是的每個學習結果都會expire，需要重新學習。
我們再來分析一個實踐中，openstack中使用openvswitch的情況，這是br-tun上的規則。
cookie=0x0, duration=802188.071s, table=10, n_packets=4885, n_bytes=347789, idle_age=730, hard_age=65534, priority=1 actions=learn(table=20,hard_timeout=300,priority=1,NXM_OF_VLAN_TCI[0..11],NXM_OF_ETH_DST[]=NXM_OF_ETH_SRC[],load:0->NXM_OF_VLAN_TCI[],load:NXM_NX_TUN_ID[]->NXM_NX_TUN_ID[],output:NXM_OF_IN_PORT[]),output:1
cookie=0x0, duration=802187.786s, table=20, n_packets=0, n_bytes=0, idle_age=65534, hard_age=65534, priority=0 actions=resubmit(,21)
cookie=0x0, duration=802038.514s, table=20, n_packets=1239, n_bytes=83620, idle_age=735, hard_age=65534, priority=2,dl_vlan=1,dl_dst=fa:16:3e:7e:ab:cc actions=strip_vlan,set_tunnel:0x3e9,output:2
cookie=0x0, duration=802187.653s, table=21, n_packets=17, n_bytes=1426, idle_age=65534, hard_age=65534, priority=0 actions=drop
cookie=0x0, duration=802055.878s, table=21, n_packets=40, n_bytes=1736, idle_age=65534, hard_age=65534, dl_vlan=1 actions=strip_vlan,set_tunnel:0x3e9,output:2
這里table 10是用來學習的。table 20是learning table。如果table 20是空的，也即還沒有學到什么，則會通過priority=0的規則resubmit到table 21.
table 21是發送規則，將br-int上的vlan tag消除，然后打上gre tunnel的id。
上面的情況中，table 20不是空的，也即發送給dl_dst=fa:16:3e:7e:ab:cc的包不用走默認規則，直接通過table 20就發送出去了。
table 20的規則是通過table 10學習得到的，table 10是一個接受規則。最終output 1，發送給了br-int
NXM_OF_VLAN_TCI[0..11]是記錄vlan tag，所以學習結果中有dl_vlan=1
NXM_OF_ETH_DST[]=NXM_OF_ETH_SRC[]是將mac source address記錄，所以結果中有dl_dst=fa:16:3e:7e:ab:cc
load:0->NXM_OF_VLAN_TCI[]意思是發送出去的時候，vlan tag設為0，所以結果中有actions=strip_vlan
load:NXM_NX_TUN_ID[]->NXM_NX_TUN_ID[]意思是發出去的時候，設置tunnul id，所以結果中有set_tunnel:0x3e9
output:NXM_OF_IN_PORT[]意思是發送給哪個port，由於是從port2進來的，因而結果中有output:2
測試一：從port 1來一個vlan為20的mac為50:00:00:00:00:01的包
$ sudo ovs-appctl ofproto/trace helloworld in_port=1,vlan_tci=20,dl_src=50:00:00:00:00:01 -generate
Flow: metadata=0,in_port=1,vlan_tci=0x0014,dl_src=50:00:00:00:00:01,dl_dst=00:00:00:00:00:00,dl_type=0x0000
Rule: table=0 cookie=0 priority=0
OpenFlow actions=resubmit(,1)
Resubmitted flow: unchanged
Resubmitted regs: reg0=0x0 reg1=0x0 reg2=0x0 reg3=0x0 reg4=0x0 reg5=0x0 reg6=0x0 reg7=0x0
Resubmitted odp: drop
Rule: table=1 cookie=0 priority=99,in_port=1
OpenFlow actions=resubmit(,2)
Resubmitted flow: unchanged
Resubmitted regs: reg0=0x0 reg1=0x0 reg2=0x0 reg3=0x0 reg4=0x0 reg5=0x0 reg6=0x0 reg7=0x0
Resubmitted odp: drop
Rule: table=2 cookie=0
OpenFlow actions=learn(table=10,NXM_OF_VLAN_TCI[0..11],NXM_OF_ETH_DST[]=NXM_OF_ETH_SRC[],load:NXM_OF_IN_PORT[]->NXM_NX_REG0[0..15]),resubmit(,3)
Resubmitted flow: unchanged
Resubmitted regs: reg0=0x0 reg1=0x0 reg2=0x0 reg3=0x0 reg4=0x0 reg5=0x0 reg6=0x0 reg7=0x0
Resubmitted odp: drop
No match
Final flow: unchanged
Relevant fields: skb_priority=0,in_port=1,vlan_tci=0x0014/0x0fff,dl_src=50:00:00:00:00:01,dl_dst=00:00:00:00:00:00/ff:ff:ff:ff:ff:f0,dl_type=0x0000,nw_frag=no
Datapath actions: drop
$ sudo ovs-ofctl dump-flows helloworld
NXST_FLOW reply (xid=0x4):
cookie=0x0, duration=90537.25s, table=0, n_packets=0, n_bytes=0, idle_age=65534, hard_age=65534, priority=0 actions=resubmit(,1)
cookie=0x0, duration=90727.209s, table=0, n_packets=0, n_bytes=0, idle_age=65534, hard_age=65534, dl_src=01:00:00:00:00:00/01:00:00:00:00:00 actions=drop
cookie=0x0, duration=90662.724s, table=0, n_packets=0, n_bytes=0, idle_age=65534, hard_age=65534, dl_dst=01:80:c2:00:00:00/ff:ff:ff:ff:ff:f0 actions=drop
cookie=0x0, duration=86147.941s, table=1, n_packets=0, n_bytes=0, idle_age=65534, hard_age=65534, priority=99,in_port=2,vlan_tci=0x0000 actions=mod_vlan_vid:20,resubmit(,2)
cookie=0x0, duration=86147.941s, table=1, n_packets=0, n_bytes=0, idle_age=65534, hard_age=65534, priority=99,in_port=4,vlan_tci=0x0000 actions=mod_vlan_vid:30,resubmit(,2)
cookie=0x0, duration=86147.941s, table=1, n_packets=0, n_bytes=0, idle_age=65534, hard_age=65534, priority=99,in_port=3,vlan_tci=0x0000 actions=mod_vlan_vid:30,resubmit(,2)
cookie=0x0, duration=86278.986s, table=1, n_packets=0, n_bytes=0, idle_age=65534, hard_age=65534, priority=99,in_port=1 actions=resubmit(,2)
cookie=0x0, duration=86357.407s, table=1, n_packets=0, n_bytes=0, idle_age=65534, hard_age=65534, priority=0 actions=drop
cookie=0x0, duration=83587.281s, table=2, n_packets=0, n_bytes=0, idle_age=65534, hard_age=65534, actions=learn(table=10,NXM_OF_VLAN_TCI[0..11],NXM_OF_ETH_DST[]=NXM_OF_ETH_SRC[],load:NXM_OF_IN_PORT[]->NXM_NX_REG0[0..15]),resubmit(,3)
cookie=0x0, duration=31.258s, table=10, n_packets=0, n_bytes=0, idle_age=31, vlan_tci=0x0014/0x0fff,dl_dst=50:00:00:00:00:01 actions=load:0x1->NXM_NX_REG0[0..15]
table 10多了一條，vlan為20，dl_dst為50:00:00:00:00:01，發送的時候從port 1出去。
測試二：從port 2進來，被打上了vlan 20，mac為50:00:00:00:00:02
$ sudo ovs-appctl ofproto/trace helloworld in_port=2,dl_src=50:00:00:00:00:02 -generate
Flow: metadata=0,in_port=2,vlan_tci=0x0000,dl_src=50:00:00:00:00:02,dl_dst=00:00:00:00:00:00,dl_type=0x0000
Rule: table=0 cookie=0 priority=0
OpenFlow actions=resubmit(,1)
Resubmitted flow: unchanged
Resubmitted regs: reg0=0x0 reg1=0x0 reg2=0x0 reg3=0x0 reg4=0x0 reg5=0x0 reg6=0x0 reg7=0x0
Resubmitted odp: drop
Rule: table=1 cookie=0 priority=99,in_port=2,vlan_tci=0x0000
OpenFlow actions=mod_vlan_vid:20,resubmit(,2)
Resubmitted flow: metadata=0,in_port=2,dl_vlan=20,dl_vlan_pcp=0,dl_src=50:00:00:00:00:02,dl_dst=00:00:00:00:00:00,dl_type=0x0000
Resubmitted regs: reg0=0x0 reg1=0x0 reg2=0x0 reg3=0x0 reg4=0x0 reg5=0x0 reg6=0x0 reg7=0x0
Resubmitted odp: drop
Rule: table=2 cookie=0
OpenFlow actions=learn(table=10,NXM_OF_VLAN_TCI[0..11],NXM_OF_ETH_DST[]=NXM_OF_ETH_SRC[],load:NXM_OF_IN_PORT[]->NXM_NX_REG0[0..15]),resubmit(,3)
Resubmitted flow: unchanged
Resubmitted regs: reg0=0x0 reg1=0x0 reg2=0x0 reg3=0x0 reg4=0x0 reg5=0x0 reg6=0x0 reg7=0x0
Resubmitted odp: drop
No match
Final flow: unchanged
Relevant fields: skb_priority=0,in_port=2,vlan_tci=0x0000,dl_src=50:00:00:00:00:02,dl_dst=00:00:00:00:00:00/ff:ff:ff:ff:ff:f0,dl_type=0x0000,nw_frag=no
Datapath actions: drop
$ sudo ovs-ofctl dump-flows helloworld
NXST_FLOW reply (xid=0x4):
cookie=0x0, duration=90823.14s, table=0, n_packets=0, n_bytes=0, idle_age=65534, hard_age=65534, priority=0 actions=resubmit(,1)
cookie=0x0, duration=91013.099s, table=0, n_packets=0, n_bytes=0, idle_age=65534, hard_age=65534, dl_src=01:00:00:00:00:00/01:00:00:00:00:00 actions=drop
cookie=0x0, duration=90948.614s, table=0, n_packets=0, n_bytes=0, idle_age=65534, hard_age=65534, dl_dst=01:80:c2:00:00:00/ff:ff:ff:ff:ff:f0 actions=drop
cookie=0x0, duration=86433.831s, table=1, n_packets=0, n_bytes=0, idle_age=65534, hard_age=65534, priority=99,in_port=2,vlan_tci=0x0000 actions=mod_vlan_vid:20,resubmit(,2)
cookie=0x0, duration=86433.831s, table=1, n_packets=0, n_bytes=0, idle_age=65534, hard_age=65534, priority=99,in_port=4,vlan_tci=0x0000 actions=mod_vlan_vid:30,resubmit(,2)
cookie=0x0, duration=86433.831s, table=1, n_packets=0, n_bytes=0, idle_age=65534, hard_age=65534, priority=99,in_port=3,vlan_tci=0x0000 actions=mod_vlan_vid:30,resubmit(,2)
cookie=0x0, duration=86564.876s, table=1, n_packets=0, n_bytes=0, idle_age=65534, hard_age=65534, priority=99,in_port=1 actions=resubmit(,2)
cookie=0x0, duration=86643.297s, table=1, n_packets=0, n_bytes=0, idle_age=65534, hard_age=65534, priority=0 actions=drop
cookie=0x0, duration=83873.171s, table=2, n_packets=0, n_bytes=0, idle_age=65534, hard_age=65534, actions=learn(table=10,NXM_OF_VLAN_TCI[0..11],NXM_OF_ETH_DST[]=NXM_OF_ETH_SRC[],load:NXM_OF_IN_PORT[]->NXM_NX_REG0[0..15]),resubmit(,3)
cookie=0x0, duration=4.472s, table=10, n_packets=0, n_bytes=0, idle_age=4, vlan_tci=0x0014/0x0fff,dl_dst=50:00:00:00:00:02 actions=load:0x2->NXM_NX_REG0[0..15]
cookie=0x0, duration=317.148s, table=10, n_packets=0, n_bytes=0, idle_age=317, vlan_tci=0x0014/0x0fff,dl_dst=50:00:00:00:00:01 actions=load:0x1->NXM_NX_REG0[0..15]
實現第四個table 3: Look Up Destination Port
在table 2中，vswtich通過進入的包，學習了vlanid –> mac –> port的映射后，對於要發送的包，可以根據學習到的table 10里面的內容，根據destination mac和vlan，來找到相應的port發送出去，而不用每次都flood
sudo ovs-ofctl add-flow helloworld "table=3 priority=50 actions=resubmit(,10), resubmit(,4)"
添加這條規則，首先到table 10中查找learn table entry，如果找不到則到table 4
如果包本身就是multicast的或者broadcast的，則不用去table 10里面取查找。
sudo ovs-ofctl add-flow helloworld "table=3 priority=99 dl_dst=01:00:00:00:00:00/01:00:00:00:00:00 actions=resubmit(,4)"
我們進行一項測試
$ sudo ovs-appctl ofproto/trace helloworld in_port=1,dl_vlan=20,dl_src=f0:00:00:00:00:01,dl_dst=90:00:00:00:00:01 -generate
Flow: metadata=0,in_port=1,dl_vlan=20,dl_vlan_pcp=0,dl_src=f0:00:00:00:00:01,dl_dst=90:00:00:00:00:01,dl_type=0x0000
Rule: table=0 cookie=0 priority=0
OpenFlow actions=resubmit(,1)
Resubmitted flow: unchanged
Resubmitted regs: reg0=0x0 reg1=0x0 reg2=0x0 reg3=0x0 reg4=0x0 reg5=0x0 reg6=0x0 reg7=0x0
Resubmitted odp: drop
Rule: table=1 cookie=0 priority=99,in_port=1
OpenFlow actions=resubmit(,2)
Resubmitted flow: unchanged
Resubmitted regs: reg0=0x0 reg1=0x0 reg2=0x0 reg3=0x0 reg4=0x0 reg5=0x0 reg6=0x0 reg7=0x0
Resubmitted odp: drop
Rule: table=2 cookie=0
OpenFlow actions=learn(table=10,NXM_OF_VLAN_TCI[0..11],NXM_OF_ETH_DST[]=NXM_OF_ETH_SRC[],load:NXM_OF_IN_PORT[]->NXM_NX_REG0[0..15]),resubmit(,3)
Resubmitted flow: unchanged
Resubmitted regs: reg0=0x0 reg1=0x0 reg2=0x0 reg3=0x0 reg4=0x0 reg5=0x0 reg6=0x0 reg7=0x0
Resubmitted odp: drop
Rule: table=3 cookie=0 priority=50
OpenFlow actions=resubmit(,10),resubmit(,4)
Resubmitted flow: unchanged
Resubmitted regs: reg0=0x0 reg1=0x0 reg2=0x0 reg3=0x0 reg4=0x0 reg5=0x0 reg6=0x0 reg7=0x0
Resubmitted odp: drop
No match
Resubmitted flow: unchanged
Resubmitted regs: reg0=0x0 reg1=0x0 reg2=0x0 reg3=0x0 reg4=0x0 reg5=0x0 reg6=0x0 reg7=0x0
Resubmitted odp: drop
No match
Final flow: unchanged
Relevant fields: skb_priority=0,in_port=1,vlan_tci=0x0014/0x0fff,dl_src=f0:00:00:00:00:01,dl_dst=90:00:00:00:00:01,dl_type=0x0000,nw_frag=no
Datapath actions: drop
由於目標地址f0:00:00:00:00:01沒有在table 10中找到，因而到達table 4.
但是這次測試使得table 10中學習到了mac地址90:00:00:00:00:01
$ sudo ovs-ofctl dump-flows helloworld
NXST_FLOW reply (xid=0x4):
cookie=0x0, duration=91588.452s, table=0, n_packets=0, n_bytes=0, idle_age=65534, hard_age=65534, priority=0 actions=resubmit(,1)
cookie=0x0, duration=91778.411s, table=0, n_packets=0, n_bytes=0, idle_age=65534, hard_age=65534, dl_src=01:00:00:00:00:00/01:00:00:00:00:00 actions=drop
cookie=0x0, duration=91713.926s, table=0, n_packets=0, n_bytes=0, idle_age=65534, hard_age=65534, dl_dst=01:80:c2:00:00:00/ff:ff:ff:ff:ff:f0 actions=drop
cookie=0x0, duration=87199.143s, table=1, n_packets=0, n_bytes=0, idle_age=65534, hard_age=65534, priority=99,in_port=2,vlan_tci=0x0000 actions=mod_vlan_vid:20,resubmit(,2)
cookie=0x0, duration=87199.143s, table=1, n_packets=0, n_bytes=0, idle_age=65534, hard_age=65534, priority=99,in_port=4,vlan_tci=0x0000 actions=mod_vlan_vid:30,resubmit(,2)
cookie=0x0, duration=87199.143s, table=1, n_packets=0, n_bytes=0, idle_age=65534, hard_age=65534, priority=99,in_port=3,vlan_tci=0x0000 actions=mod_vlan_vid:30,resubmit(,2)
cookie=0x0, duration=87330.188s, table=1, n_packets=0, n_bytes=0, idle_age=65534, hard_age=65534, priority=99,in_port=1 actions=resubmit(,2)
cookie=0x0, duration=87408.609s, table=1, n_packets=0, n_bytes=0, idle_age=65534, hard_age=65534, priority=0 actions=drop
cookie=0x0, duration=84638.483s, table=2, n_packets=0, n_bytes=0, idle_age=65534, hard_age=65534, actions=learn(table=10,NXM_OF_VLAN_TCI[0..11],NXM_OF_ETH_DST[]=NXM_OF_ETH_SRC[],load:NXM_OF_IN_PORT[]->NXM_NX_REG0[0..15]),resubmit(,3)
cookie=0x0, duration=352.841s, table=3, n_packets=0, n_bytes=0, idle_age=352, priority=50 actions=resubmit(,10),resubmit(,4)
cookie=0x0, duration=212.704s, table=3, n_packets=0, n_bytes=0, idle_age=212, priority=99,dl_dst=01:00:00:00:00:00/01:00:00:00:00:00 actions=resubmit(,4)
cookie=0x0, duration=117.364s, table=10, n_packets=0, n_bytes=0, idle_age=117, vlan_tci=0x0014/0x0fff,dl_dst=f0:00:00:00:00:01 actions=load:0x1->NXM_NX_REG0[0..15]
cookie=0x0, duration=769.784s, table=10, n_packets=0, n_bytes=0, idle_age=769, vlan_tci=0x0014/0x0fff,dl_dst=50:00:00:00:00:02 actions=load:0x2->NXM_NX_REG0[0..15]
cookie=0x0, duration=1082.46s, table=10, n_packets=0, n_bytes=0, idle_age=1082, vlan_tci=0x0014/0x0fff,dl_dst=50:00:00:00:00:01 actions=load:0x1->NXM_NX_REG0[0..15]
下面我們進行另一個測試
$ sudo ovs-appctl ofproto/trace helloworld in_port=2,dl_src=90:00:00:00:00:01,dl_dst=f0:00:00:00:00:01 -generate
Flow: metadata=0,in_port=2,vlan_tci=0x0000,dl_src=90:00:00:00:00:01,dl_dst=f0:00:00:00:00:01,dl_type=0x0000
Rule: table=0 cookie=0 priority=0
OpenFlow actions=resubmit(,1)
Resubmitted flow: unchanged
Resubmitted regs: reg0=0x0 reg1=0x0 reg2=0x0 reg3=0x0 reg4=0x0 reg5=0x0 reg6=0x0 reg7=0x0
Resubmitted odp: drop
Rule: table=1 cookie=0 priority=99,in_port=2,vlan_tci=0x0000
OpenFlow actions=mod_vlan_vid:20,resubmit(,2)
Resubmitted flow: metadata=0,in_port=2,dl_vlan=20,dl_vlan_pcp=0,dl_src=90:00:00:00:00:01,dl_dst=f0:00:00:00:00:01,dl_type=0x0000
Resubmitted regs: reg0=0x0 reg1=0x0 reg2=0x0 reg3=0x0 reg4=0x0 reg5=0x0 reg6=0x0 reg7=0x0
Resubmitted odp: drop
Rule: table=2 cookie=0
OpenFlow actions=learn(table=10,NXM_OF_VLAN_TCI[0..11],NXM_OF_ETH_DST[]=NXM_OF_ETH_SRC[],load:NXM_OF_IN_PORT[]->NXM_NX_REG0[0..15]),resubmit(,3)
Resubmitted flow: unchanged
Resubmitted regs: reg0=0x0 reg1=0x0 reg2=0x0 reg3=0x0 reg4=0x0 reg5=0x0 reg6=0x0 reg7=0x0
Resubmitted odp: drop
Rule: table=3 cookie=0 priority=50
OpenFlow actions=resubmit(,10),resubmit(,4)
Resubmitted flow: unchanged
Resubmitted regs: reg0=0x0 reg1=0x0 reg2=0x0 reg3=0x0 reg4=0x0 reg5=0x0 reg6=0x0 reg7=0x0
Resubmitted odp: drop
Rule: table=10 cookie=0 vlan_tci=0x0014/0x0fff,dl_dst=f0:00:00:00:00:01
OpenFlow actions=load:0x1->NXM_NX_REG0[0..15]
Resubmitted flow: reg0=0x1,metadata=0,in_port=2,dl_vlan=20,dl_vlan_pcp=0,dl_src=90:00:00:00:00:01,dl_dst=f0:00:00:00:00:01,dl_type=0x0000
Resubmitted regs: reg0=0x1 reg1=0x0 reg2=0x0 reg3=0x0 reg4=0x0 reg5=0x0 reg6=0x0 reg7=0x0
Resubmitted odp: drop
No match
Final flow: unchanged
Relevant fields: skb_priority=0,in_port=2,vlan_tci=0x0000,dl_src=90:00:00:00:00:01,dl_dst=f0:00:00:00:00:01,dl_type=0x0000,nw_frag=no
Datapath actions: drop
因為剛才學習到了mac地址f0:00:00:00:00:01，所以這次在table 10中找到了這條記錄，這次同時也學習到了mac地址90:00:00:00:00:01
下面我們再發送第一次的包
$ sudo ovs-appctl ofproto/trace helloworld in_port=1,dl_vlan=20,dl_src=f0:00:00:00:00:01,dl_dst=90:00:00:00:00:01 -generate
Flow: metadata=0,in_port=1,dl_vlan=20,dl_vlan_pcp=0,dl_src=f0:00:00:00:00:01,dl_dst=90:00:00:00:00:01,dl_type=0x0000
Rule: table=0 cookie=0 priority=0
OpenFlow actions=resubmit(,1)
Resubmitted flow: unchanged
Resubmitted regs: reg0=0x0 reg1=0x0 reg2=0x0 reg3=0x0 reg4=0x0 reg5=0x0 reg6=0x0 reg7=0x0
Resubmitted odp: drop
Rule: table=1 cookie=0 priority=99,in_port=1
OpenFlow actions=resubmit(,2)
Resubmitted flow: unchanged
Resubmitted regs: reg0=0x0 reg1=0x0 reg2=0x0 reg3=0x0 reg4=0x0 reg5=0x0 reg6=0x0 reg7=0x0
Resubmitted odp: drop
Rule: table=2 cookie=0
OpenFlow actions=learn(table=10,NXM_OF_VLAN_TCI[0..11],NXM_OF_ETH_DST[]=NXM_OF_ETH_SRC[],load:NXM_OF_IN_PORT[]->NXM_NX_REG0[0..15]),resubmit(,3)
Resubmitted flow: unchanged
Resubmitted regs: reg0=0x0 reg1=0x0 reg2=0x0 reg3=0x0 reg4=0x0 reg5=0x0 reg6=0x0 reg7=0x0
Resubmitted odp: drop
Rule: table=3 cookie=0 priority=50
OpenFlow actions=resubmit(,10),resubmit(,4)
Resubmitted flow: unchanged
Resubmitted regs: reg0=0x0 reg1=0x0 reg2=0x0 reg3=0x0 reg4=0x0 reg5=0x0 reg6=0x0 reg7=0x0
Resubmitted odp: drop
Rule: table=10 cookie=0 vlan_tci=0x0014/0x0fff,dl_dst=90:00:00:00:00:01
OpenFlow actions=load:0x2->NXM_NX_REG0[0..15]
Resubmitted flow: reg0=0x2,metadata=0,in_port=1,dl_vlan=20,dl_vlan_pcp=0,dl_src=f0:00:00:00:00:01,dl_dst=90:00:00:00:00:01,dl_type=0x0000
Resubmitted regs: reg0=0x2 reg1=0x0 reg2=0x0 reg3=0x0 reg4=0x0 reg5=0x0 reg6=0x0 reg7=0x0
Resubmitted odp: drop
No match
Final flow: unchanged
Relevant fields: skb_priority=0,in_port=1,vlan_tci=0x0014/0x0fff,dl_src=f0:00:00:00:00:01,dl_dst=90:00:00:00:00:01,dl_type=0x0000,nw_frag=no
Datapath actions: drop
發現也在table 10中找到了記錄
實現第五個table 4: Output Processing
這個時候，register 0中包含了output port，如果是0則說明是flood。
對於port 1來講，是trunk port，所以攜帶的vlan tag就讓他帶着，從port 1出去。
sudo ovs-ofctl add-flow helloworld "table=4 reg0=1 actions=1"
對於port 2來講，是vlan 20的，然而出去的時候，vlan tag會被抹掉，從port 2發出去
對於port 3， 4來講，是vlan 30的，然而出去的時候，vlan tag會被抹掉，從port 3, 4出去
$ sudo ovs-ofctl add-flows helloworld - <<'EOF'
table=4 reg0=2 actions=strip_vlan,2
table=4 reg0=3 actions=strip_vlan,3
table=4 reg0=4 actions=strip_vlan,4
EOF
對於broadcast來講，我們希望一個vlan的broadcast僅僅在這個vlan里面發送，不影響其他的vlan。
$ sudo ovs-ofctl add-flows helloworld - <<'EOF'
table=4 reg0=0 priority=99 dl_vlan=20 actions=1,strip_vlan,2
table=4 reg0=0 priority=99 dl_vlan=30 actions=1,strip_vlan,3,4
table=4 reg0=0 priority=50 actions=1
EOF
所以對於register = 0的，也即是broadcast的，屬於vlan 20的，則從port 1, 2出去，屬於vlan 30的，則從port 1, 3, 4出去。
$ sudo ovs-ofctl dump-flows helloworld
NXST_FLOW reply (xid=0x4):
cookie=0x0, duration=92909.119s, table=0, n_packets=0, n_bytes=0, idle_age=65534, hard_age=65534, priority=0 actions=resubmit(,1)
cookie=0x0, duration=93099.078s, table=0, n_packets=0, n_bytes=0, idle_age=65534, hard_age=65534, dl_src=01:00:00:00:00:00/01:00:00:00:00:00 actions=drop
cookie=0x0, duration=93034.593s, table=0, n_packets=0, n_bytes=0, idle_age=65534, hard_age=65534, dl_dst=01:80:c2:00:00:00/ff:ff:ff:ff:ff:f0 actions=drop
cookie=0x0, duration=88519.81s, table=1, n_packets=0, n_bytes=0, idle_age=65534, hard_age=65534, priority=99,in_port=2,vlan_tci=0x0000 actions=mod_vlan_vid:20,resubmit(,2)
cookie=0x0, duration=88519.81s, table=1, n_packets=0, n_bytes=0, idle_age=65534, hard_age=65534, priority=99,in_port=4,vlan_tci=0x0000 actions=mod_vlan_vid:30,resubmit(,2)
cookie=0x0, duration=88519.81s, table=1, n_packets=0, n_bytes=0, idle_age=65534, hard_age=65534, priority=99,in_port=3,vlan_tci=0x0000 actions=mod_vlan_vid:30,resubmit(,2)
cookie=0x0, duration=88650.855s, table=1, n_packets=0, n_bytes=0, idle_age=65534, hard_age=65534, priority=99,in_port=1 actions=resubmit(,2)
cookie=0x0, duration=88729.276s, table=1, n_packets=0, n_bytes=0, idle_age=65534, hard_age=65534, priority=0 actions=drop
cookie=0x0, duration=85959.15s, table=2, n_packets=0, n_bytes=0, idle_age=65534, hard_age=65534, actions=learn(table=10,NXM_OF_VLAN_TCI[0..11],NXM_OF_ETH_DST[]=NXM_OF_ETH_SRC[],load:NXM_OF_IN_PORT[]->NXM_NX_REG0[0..15]),resubmit(,3)
cookie=0x0, duration=1673.508s, table=3, n_packets=0, n_bytes=0, idle_age=1673, priority=50 actions=resubmit(,10),resubmit(,4)
cookie=0x0, duration=1533.371s, table=3, n_packets=0, n_bytes=0, idle_age=1533, priority=99,dl_dst=01:00:00:00:00:00/01:00:00:00:00:00 actions=resubmit(,4)
cookie=0x0, duration=332.478s, table=4, n_packets=0, n_bytes=0, idle_age=332, reg0=0x3 actions=strip_vlan,output:3
cookie=0x0, duration=228.839s, table=4, n_packets=0, n_bytes=0, idle_age=228, priority=50,reg0=0x0 actions=output:1
cookie=0x0, duration=483.068s, table=4, n_packets=0, n_bytes=0, idle_age=483, reg0=0x1 actions=output:1
cookie=0x0, duration=332.478s, table=4, n_packets=0, n_bytes=0, idle_age=332, reg0=0x4 actions=strip_vlan,output:4
cookie=0x0, duration=332.478s, table=4, n_packets=0, n_bytes=0, idle_age=332, reg0=0x2 actions=strip_vlan,output:2
cookie=0x0, duration=228.84s, table=4, n_packets=0, n_bytes=0, idle_age=228, priority=99,reg0=0x0,dl_vlan=30 actions=output:1,strip_vlan,output:3,output:4
cookie=0x0, duration=228.84s, table=4, n_packets=0, n_bytes=0, idle_age=228, priority=99,reg0=0x0,dl_vlan=20 actions=output:1,strip_vlan,output:2
cookie=0x0, duration=1438.031s, table=10, n_packets=0, n_bytes=0, idle_age=1438, hard_age=1109, vlan_tci=0x0014/0x0fff,dl_dst=f0:00:00:00:00:01 actions=load:0x1->NXM_NX_REG0[0..15]
cookie=0x0, duration=2090.451s, table=10, n_packets=0, n_bytes=0, idle_age=2090, vlan_tci=0x0014/0x0fff,dl_dst=50:00:00:00:00:02 actions=load:0x2->NXM_NX_REG0[0..15]
cookie=0x0, duration=1258.881s, table=10, n_packets=0, n_bytes=0, idle_age=1258, vlan_tci=0x0014/0x0fff,dl_dst=90:00:00:00:00:01 actions=load:0x2->NXM_NX_REG0[0..15]
cookie=0x0, duration=2403.127s, table=10, n_packets=0, n_bytes=0, idle_age=2403, vlan_tci=0x0014/0x0fff,dl_dst=50:00:00:00:00:01 actions=load:0x1->NXM_NX_REG0[0..15]
首先來測試一個multicast和broadcast
如果是一個port 1來的vlan 30的broadcast
$ sudo ovs-appctl ofproto/trace helloworld in_port=1,dl_dst=ff:ff:ff:ff:ff:ff,dl_vlan=30
Flow: metadata=0,in_port=1,dl_vlan=30,dl_vlan_pcp=0,dl_src=00:00:00:00:00:00,dl_dst=ff:ff:ff:ff:ff:ff,dl_type=0x0000
Rule: table=0 cookie=0 priority=0
OpenFlow actions=resubmit(,1)
Resubmitted flow: unchanged
Resubmitted regs: reg0=0x0 reg1=0x0 reg2=0x0 reg3=0x0 reg4=0x0 reg5=0x0 reg6=0x0 reg7=0x0
Resubmitted odp: drop
Rule: table=1 cookie=0 priority=99,in_port=1
OpenFlow actions=resubmit(,2)
Resubmitted flow: unchanged
Resubmitted regs: reg0=0x0 reg1=0x0 reg2=0x0 reg3=0x0 reg4=0x0 reg5=0x0 reg6=0x0 reg7=0x0
Resubmitted odp: drop
Rule: table=2 cookie=0
OpenFlow actions=learn(table=10,NXM_OF_VLAN_TCI[0..11],NXM_OF_ETH_DST[]=NXM_OF_ETH_SRC[],load:NXM_OF_IN_PORT[]->NXM_NX_REG0[0..15]),resubmit(,3)
Resubmitted flow: unchanged
Resubmitted regs: reg0=0x0 reg1=0x0 reg2=0x0 reg3=0x0 reg4=0x0 reg5=0x0 reg6=0x0 reg7=0x0
Resubmitted odp: drop
Rule: table=3 cookie=0 priority=99,dl_dst=01:00:00:00:00:00/01:00:00:00:00:00
OpenFlow actions=resubmit(,4)
Resubmitted flow: unchanged
Resubmitted regs: reg0=0x0 reg1=0x0 reg2=0x0 reg3=0x0 reg4=0x0 reg5=0x0 reg6=0x0 reg7=0x0
Resubmitted odp: drop
Rule: table=4 cookie=0 priority=99,reg0=0x0,dl_vlan=30
OpenFlow actions=output:1,strip_vlan,output:3,output:4
skipping output to input port
Final flow: metadata=0,in_port=1,vlan_tci=0x0000,dl_src=00:00:00:00:00:00,dl_dst=ff:ff:ff:ff:ff:ff,dl_type=0x0000
Relevant fields: skb_priority=0,in_port=1,dl_vlan=30,dl_vlan_pcp=0,dl_src=00:00:00:00:00:00,dl_dst=ff:ff:ff:ff:ff:f0/ff:ff:ff:ff:ff:f0,dl_type=0x0000,nw_frag=no
Datapath actions: pop_vlan,12,13
結果是port 1就不發送了，發送給了port 3, 4
$ sudo ovs-appctl ofproto/trace helloworld in_port=3,dl_dst=ff:ff:ff:ff:ff:ff
Flow: metadata=0,in_port=3,vlan_tci=0x0000,dl_src=00:00:00:00:00:00,dl_dst=ff:ff:ff:ff:ff:ff,dl_type=0x0000
Rule: table=0 cookie=0 priority=0
OpenFlow actions=resubmit(,1)
Resubmitted flow: unchanged
Resubmitted regs: reg0=0x0 reg1=0x0 reg2=0x0 reg3=0x0 reg4=0x0 reg5=0x0 reg6=0x0 reg7=0x0
Resubmitted odp: drop
Rule: table=1 cookie=0 priority=99,in_port=3,vlan_tci=0x0000
OpenFlow actions=mod_vlan_vid:30,resubmit(,2)
Resubmitted flow: metadata=0,in_port=3,dl_vlan=30,dl_vlan_pcp=0,dl_src=00:00:00:00:00:00,dl_dst=ff:ff:ff:ff:ff:ff,dl_type=0x0000
Resubmitted regs: reg0=0x0 reg1=0x0 reg2=0x0 reg3=0x0 reg4=0x0 reg5=0x0 reg6=0x0 reg7=0x0
Resubmitted odp: drop
Rule: table=2 cookie=0
OpenFlow actions=learn(table=10,NXM_OF_VLAN_TCI[0..11],NXM_OF_ETH_DST[]=NXM_OF_ETH_SRC[],load:NXM_OF_IN_PORT[]->NXM_NX_REG0[0..15]),resubmit(,3)
Resubmitted flow: unchanged
Resubmitted regs: reg0=0x0 reg1=0x0 reg2=0x0 reg3=0x0 reg4=0x0 reg5=0x0 reg6=0x0 reg7=0x0
Resubmitted odp: drop
Rule: table=3 cookie=0 priority=99,dl_dst=01:00:00:00:00:00/01:00:00:00:00:00
OpenFlow actions=resubmit(,4)
Resubmitted flow: unchanged
Resubmitted regs: reg0=0x0 reg1=0x0 reg2=0x0 reg3=0x0 reg4=0x0 reg5=0x0 reg6=0x0 reg7=0x0
Resubmitted odp: drop
Rule: table=4 cookie=0 priority=99,reg0=0x0,dl_vlan=30
OpenFlow actions=output:1,strip_vlan,output:3,output:4
skipping output to input port
Final flow: metadata=0,in_port=3,vlan_tci=0x0000,dl_src=00:00:00:00:00:00,dl_dst=ff:ff:ff:ff:ff:ff,dl_type=0x0000
Relevant fields: skb_priority=0,in_port=3,vlan_tci=0x0000,dl_src=00:00:00:00:00:00,dl_dst=ff:ff:ff:ff:ff:f0/ff:ff:ff:ff:ff:f0,dl_type=0x0000,nw_frag=no
Datapath actions: push_vlan(vid=30,pcp=0),10,pop_vlan,13
接着我們測試mac learning
$ sudo ovs-appctl ofproto/trace helloworld in_port=1,dl_vlan=30,dl_src=10:00:00:00:00:01,dl_dst=20:00:00:00:00:01 -generate
Flow: metadata=0,in_port=1,dl_vlan=30,dl_vlan_pcp=0,dl_src=10:00:00:00:00:01,dl_dst=20:00:00:00:00:01,dl_type=0x0000
Rule: table=0 cookie=0 priority=0
OpenFlow actions=resubmit(,1)
Resubmitted flow: unchanged
Resubmitted regs: reg0=0x0 reg1=0x0 reg2=0x0 reg3=0x0 reg4=0x0 reg5=0x0 reg6=0x0 reg7=0x0
Resubmitted odp: drop
Rule: table=1 cookie=0 priority=99,in_port=1
OpenFlow actions=resubmit(,2)
Resubmitted flow: unchanged
Resubmitted regs: reg0=0x0 reg1=0x0 reg2=0x0 reg3=0x0 reg4=0x0 reg5=0x0 reg6=0x0 reg7=0x0
Resubmitted odp: drop
Rule: table=2 cookie=0
OpenFlow actions=learn(table=10,NXM_OF_VLAN_TCI[0..11],NXM_OF_ETH_DST[]=NXM_OF_ETH_SRC[],load:NXM_OF_IN_PORT[]->NXM_NX_REG0[0..15]),resubmit(,3)
Resubmitted flow: unchanged
Resubmitted regs: reg0=0x0 reg1=0x0 reg2=0x0 reg3=0x0 reg4=0x0 reg5=0x0 reg6=0x0 reg7=0x0
Resubmitted odp: drop
Rule: table=3 cookie=0 priority=50
OpenFlow actions=resubmit(,10),resubmit(,4)
Resubmitted flow: unchanged
Resubmitted regs: reg0=0x0 reg1=0x0 reg2=0x0 reg3=0x0 reg4=0x0 reg5=0x0 reg6=0x0 reg7=0x0
Resubmitted odp: drop
No match
Resubmitted flow: unchanged
Resubmitted regs: reg0=0x0 reg1=0x0 reg2=0x0 reg3=0x0 reg4=0x0 reg5=0x0 reg6=0x0 reg7=0x0
Resubmitted odp: drop
Rule: table=4 cookie=0 priority=99,reg0=0x0,dl_vlan=30
OpenFlow actions=output:1,strip_vlan,output:3,output:4
skipping output to input port
Final flow: metadata=0,in_port=1,vlan_tci=0x0000,dl_src=10:00:00:00:00:01,dl_dst=20:00:00:00:00:01,dl_type=0x0000
Relevant fields: skb_priority=0,in_port=1,dl_vlan=30,dl_vlan_pcp=0,dl_src=10:00:00:00:00:01,dl_dst=20:00:00:00:00:01,dl_type=0x0000,nw_frag=no
Datapath actions: pop_vlan,12,13
由於這兩個地址沒有出現過，則除了進行學習以外，廣播發送給port 3，4
$ sudo ovs-appctl ofproto/trace helloworld in_port=4,dl_src=20:00:00:00:00:01,dl_dst=10:00:00:00:00:01 -generate
Flow: metadata=0,in_port=4,vlan_tci=0x0000,dl_src=20:00:00:00:00:01,dl_dst=10:00:00:00:00:01,dl_type=0x0000
Rule: table=0 cookie=0 priority=0
OpenFlow actions=resubmit(,1)
Resubmitted flow: unchanged
Resubmitted regs: reg0=0x0 reg1=0x0 reg2=0x0 reg3=0x0 reg4=0x0 reg5=0x0 reg6=0x0 reg7=0x0
Resubmitted odp: drop
Rule: table=1 cookie=0 priority=99,in_port=4,vlan_tci=0x0000
OpenFlow actions=mod_vlan_vid:30,resubmit(,2)
Resubmitted flow: metadata=0,in_port=4,dl_vlan=30,dl_vlan_pcp=0,dl_src=20:00:00:00:00:01,dl_dst=10:00:00:00:00:01,dl_type=0x0000
Resubmitted regs: reg0=0x0 reg1=0x0 reg2=0x0 reg3=0x0 reg4=0x0 reg5=0x0 reg6=0x0 reg7=0x0
Resubmitted odp: drop
Rule: table=2 cookie=0
OpenFlow actions=learn(table=10,NXM_OF_VLAN_TCI[0..11],NXM_OF_ETH_DST[]=NXM_OF_ETH_SRC[],load:NXM_OF_IN_PORT[]->NXM_NX_REG0[0..15]),resubmit(,3)
Resubmitted flow: unchanged
Resubmitted regs: reg0=0x0 reg1=0x0 reg2=0x0 reg3=0x0 reg4=0x0 reg5=0x0 reg6=0x0 reg7=0x0
Resubmitted odp: drop
Rule: table=3 cookie=0 priority=50
OpenFlow actions=resubmit(,10),resubmit(,4)
Resubmitted flow: unchanged
Resubmitted regs: reg0=0x0 reg1=0x0 reg2=0x0 reg3=0x0 reg4=0x0 reg5=0x0 reg6=0x0 reg7=0x0
Resubmitted odp: drop
Rule: table=10 cookie=0 vlan_tci=0x001e/0x0fff,dl_dst=10:00:00:00:00:01
OpenFlow actions=load:0x1->NXM_NX_REG0[0..15]
Resubmitted flow: reg0=0x1,metadata=0,in_port=4,dl_vlan=30,dl_vlan_pcp=0,dl_src=20:00:00:00:00:01,dl_dst=10:00:00:00:00:01,dl_type=0x0000
Resubmitted regs: reg0=0x1 reg1=0x0 reg2=0x0 reg3=0x0 reg4=0x0 reg5=0x0 reg6=0x0 reg7=0x0
Resubmitted odp: drop
Rule: table=4 cookie=0 reg0=0x1
OpenFlow actions=output:1
Final flow: unchanged
Relevant fields: skb_priority=0,in_port=4,vlan_tci=0x0000,dl_src=20:00:00:00:00:01,dl_dst=10:00:00:00:00:01,dl_type=0x0000,nw_frag=no
Datapath actions: push_vlan(vid=30,pcp=0),10
回復的時候，由於學習過了，則僅僅從port 1發送出去。
$ sudo ovs-appctl ofproto/trace helloworld in_port=1,dl_vlan=30,dl_src=10:00:00:00:00:01,dl_dst=20:00:00:00:00:01 -generate
Flow: metadata=0,in_port=1,dl_vlan=30,dl_vlan_pcp=0,dl_src=10:00:00:00:00:01,dl_dst=20:00:00:00:00:01,dl_type=0x0000
Rule: table=0 cookie=0 priority=0
OpenFlow actions=resubmit(,1)
Resubmitted flow: unchanged
Resubmitted regs: reg0=0x0 reg1=0x0 reg2=0x0 reg3=0x0 reg4=0x0 reg5=0x0 reg6=0x0 reg7=0x0
Resubmitted odp: drop
Rule: table=1 cookie=0 priority=99,in_port=1
OpenFlow actions=resubmit(,2)
Resubmitted flow: unchanged
Resubmitted regs: reg0=0x0 reg1=0x0 reg2=0x0 reg3=0x0 reg4=0x0 reg5=0x0 reg6=0x0 reg7=0x0
Resubmitted odp: drop
Rule: table=2 cookie=0
OpenFlow actions=learn(table=10,NXM_OF_VLAN_TCI[0..11],NXM_OF_ETH_DST[]=NXM_OF_ETH_SRC[],load:NXM_OF_IN_PORT[]->NXM_NX_REG0[0..15]),resubmit(,3)
Resubmitted flow: unchanged
Resubmitted regs: reg0=0x0 reg1=0x0 reg2=0x0 reg3=0x0 reg4=0x0 reg5=0x0 reg6=0x0 reg7=0x0
Resubmitted odp: drop
Rule: table=3 cookie=0 priority=50
OpenFlow actions=resubmit(,10),resubmit(,4)
Resubmitted flow: unchanged
Resubmitted regs: reg0=0x0 reg1=0x0 reg2=0x0 reg3=0x0 reg4=0x0 reg5=0x0 reg6=0x0 reg7=0x0
Resubmitted odp: drop
Rule: table=10 cookie=0 vlan_tci=0x001e/0x0fff,dl_dst=20:00:00:00:00:01
OpenFlow actions=load:0x4->NXM_NX_REG0[0..15]
Resubmitted flow: reg0=0x4,metadata=0,in_port=1,dl_vlan=30,dl_vlan_pcp=0,dl_src=10:00:00:00:00:01,dl_dst=20:00:00:00:00:01,dl_type=0x0000
Resubmitted regs: reg0=0x4 reg1=0x0 reg2=0x0 reg3=0x0 reg4=0x0 reg5=0x0 reg6=0x0 reg7=0x0
Resubmitted odp: drop
Rule: table=4 cookie=0 reg0=0x4
OpenFlow actions=strip_vlan,output:4
Final flow: reg0=0x4,metadata=0,in_port=1,vlan_tci=0x0000,dl_src=10:00:00:00:00:01,dl_dst=20:00:00:00:00:01,dl_type=0x0000
Relevant fields: skb_priority=0,in_port=1,dl_vlan=30,dl_vlan_pcp=0,dl_src=10:00:00:00:00:01,dl_dst=20:00:00:00:00:01,dl_type=0x0000,nw_frag=no
Datapath actions: pop_vlan,13
由於在回復中進行了學習，因而發送的時候，僅僅發送port 4