neutron基础三（linuxbridges）

需要基础二 veth peer和namespace的例子
先建一个veth peer，
外面的IP是veth0 192.168.3.1/29
namespace里面的ip是veth 192.168.3.2/29
主机的ip是192.168.137.55

[root@centos7 ~]# brctl addbr mybridge
[root@centos7 ~]# brctl show
bridge name     bridge id               STP enabled     interfaces
mybridge                8000.000000000000       no
virbr0          8000.5254007194cc       yes             virbr0-nic

[root@centos7 ~]# ip link
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN mode DEFAULT 
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP mode DEFAULT qlen 1000
    link/ether 50:50:18:aa:80:17 brd ff:ff:ff:ff:ff:ff
3: virbr0: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc noqueue state DOWN mode DEFAULT 
    link/ether 52:54:00:71:94:cc brd ff:ff:ff:ff:ff:ff
4: virbr0-nic: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc pfifo_fast master virbr0 state DOWN mode DEFAULT qlen 500
    link/ether 52:54:00:71:94:cc brd ff:ff:ff:ff:ff:ff
5: veth0@if6: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP mode DEFAULT qlen 1000
    link/ether be:ab:06:b0:59:fa brd ff:ff:ff:ff:ff:ff link-netnsid 0
7: mybridge: <BROADCAST,MULTICAST> mtu 1500 qdisc noop state DOWN mode DEFAULT 
    link/ether fa:22:e9:ca:f0:bd brd ff:ff:ff:ff:ff:ff
[root@centos7 ~]# ip link set dev mybridge up
[root@centos7 ~]# brctl showmacs mybridge
port no mac addr                is local?       ageing timer

[root@centos7 ~]# bridge fdb
01:00:5e:00:00:01 dev eth0 self permanent
33:33:00:00:00:01 dev eth0 self permanent
33:33:ff:aa:80:17 dev eth0 self permanent
01:00:5e:00:00:fb dev eth0 self permanent
52:54:00:71:94:cc dev virbr0-nic vlan 1 master virbr0 permanent
52:54:00:71:94:cc dev virbr0-nic master virbr0 permanent
0a:a5:d6:5b:db:94 dev virbr0 vlan 1 master virbr0 permanent
01:00:5e:00:00:01 dev virbr0-nic self permanent
33:33:00:00:00:01 dev veth0 self permanent
01:00:5e:00:00:01 dev veth0 self permanent
01:00:5e:00:00:fb dev veth0 self permanent
33:33:ff:b0:59:fa dev veth0 self permanent
fa:22:e9:ca:f0:bd dev mybridge vlan 1 master mybridge permanent

[root@centos7 ~]# brctl addif mybridge veth0
[root@centos7 ~]# brctl show
bridge name     bridge id               STP enabled     interfaces
mybridge                8000.beab06b059fa       no              veth0
virbr0          8000.5254007194cc       yes             virbr0-nic
[root@centos7 ~]# brctl show macs mybridge
bridge name     bridge id               STP enabled     interfaces
macs            can't get info No such device
mybridge                8000.beab06b059fa       no              veth0

[root@centos7 ~]# ip netns exec test ping 192.168.139.55
PING 192.168.139.55 (192.168.139.55) 56(84) bytes of data.
From 192.168.3.2 icmp_seq=10 Destination Host Unreachable
From 192.168.3.2 icmp_seq=11 Destination Host Unreachable
From 192.168.3.2 icmp_seq=12 Destination Host Unreachable
From 192.168.3.2 icmp_seq=13 Destination Host Unreachable
From 192.168.3.2 icmp_seq=14 Destination Host Unreachable
From 192.168.3.2 icmp_seq=15 Destination Host Unreachable
From 192.168.3.2 icmp_seq=16 Destination Host Unreachable
From 192.168.3.2 icmp_seq=17 Destination Host Unreachable
From 192.168.3.2 icmp_seq=18 Destination Host Unreachable
From 192.168.3.2 icmp_seq=19 Destination Host Unreachable
From 192.168.3.2 icmp_seq=20 Destination Host Unreachable
From 192.168.3.2 icmp_seq=21 Destination Host Unreachable
^C
--- 192.168.139.55 ping statistics ---
22 packets transmitted, 0 received, +12 errors, 100% packet loss, time 21003ms
pipe 4
[root@centos7 ~]# 

另一个ssh终端：

[root@centos7 ~]# tcpdump -i mybridge -e -v
tcpdump: WARNING: mybridge: no IPv4 address assigned
tcpdump: listening on mybridge, link-type EN10MB (Ethernet), capture size 65535 bytes
01:53:50.912984 ba:3f:cf:12:23:5d (oui Unknown) > Broadcast, ethertype ARP (0x0806), length 42: Ethernet (len 6), IPv4 (len 4), Request who-has localhost tell localhost, length 28
01:53:51.915018 ba:3f:cf:12:23:5d (oui Unknown) > Broadcast, ethertype ARP (0x0806), length 42: Ethernet (len 6), IPv4 (len 4), Request who-has localhost tell localhost, length 28
01:53:52.916979 ba:3f:cf:12:23:5d (oui Unknown) > Broadcast, ethertype ARP (0x0806), length 42: Ethernet (len 6), IPv4 (len 4), Request who-has localhost tell localhost, length 28
^C

我们发现，从namespace里面ping主机的ip，ping不通了

把外面veth0的IP
现在给

[root@centos7 ~]# ip addr del dev veth0 192.168.3.1/29
[root@centos7 ~]# 
[root@centos7 ~]# ip addr
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN 
    link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
    inet 127.0.0.1/8 scope host lo
       valid_lft forever preferred_lft forever
    inet6 ::1/128 scope host 
       valid_lft forever preferred_lft forever
2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 1000
    link/ether 50:50:18:aa:80:17 brd ff:ff:ff:ff:ff:ff
    inet 192.168.139.55/20 brd 192.168.143.255 scope global dynamic eth0
       valid_lft 3479sec preferred_lft 3479sec
    inet6 fe80::5250:18ff:feaa:8017/64 scope link 
       valid_lft forever preferred_lft forever
3: virbr0: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc noqueue state DOWN 
    link/ether 52:54:00:71:94:cc brd ff:ff:ff:ff:ff:ff
    inet 192.168.122.1/24 brd 192.168.122.255 scope global virbr0
       valid_lft forever preferred_lft forever
4: virbr0-nic: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc pfifo_fast master virbr0 state DOWN qlen 500
    link/ether 52:54:00:71:94:cc brd ff:ff:ff:ff:ff:ff
5: veth0@if6: <BROADCAST,MULTICAST> mtu 1500 qdisc pfifo_fast master mybridge state DOWN qlen 1000
    link/ether be:ab:06:b0:59:fa brd ff:ff:ff:ff:ff:ff link-netnsid 0
7: mybridge: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc noqueue state DOWN 
    link/ether be:ab:06:b0:59:fa brd ff:ff:ff:ff:ff:ff
    inet6 fe80::bcab:6ff:feb0:59fa/64 scope link 
       valid_lft forever preferred_lft forever
[root@centos7 ~]# ip addr add dev mybridge 192.168.3.1/29
[root@centos7 ~]# ip link set dev veth0 up

测试：

[root@centos7 ~]# ip netns exec test ping 192.168.139.55
PING 192.168.139.55 (192.168.139.55) 56(84) bytes of data.
64 bytes from 192.168.139.55: icmp_seq=1 ttl=64 time=0.111 ms
^C
--- 192.168.139.55 ping statistics ---
1 packets transmitted, 1 received, 0% packet loss, time 0ms
rtt min/avg/max/mdev = 0.111/0.111/0.111/0.000 ms
[root@centos7 ~]#