有一个 CentOS KVM 主机，上面的几个客户机通过 br0 桥接器与真实的外部 IP 一起工作良好
现在创建新的 Guest，为其提供真正的静态 IP（就像我对其他 GUEST 所做的那样），但不能上网。但新 GUEST 可以 ping 通 HOST 和此 HOST 上的其他 GUEST
主机 ifconfig
# ifconfig
br0: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500
inet 62.*.*.44 netmask 255.255.255.0 broadcast 62.*.*.255
inet6 fe80::225:90ff:fe2e:d8a8 prefixlen 64 scopeid 0x20<link>
ether 00:25:90:2e:d8:a8 txqueuelen 1000 (Ethernet)
RX packets 681705441 bytes 1105019968953 (1.0 TiB)
RX errors 0 dropped 124860 overruns 0 frame 0
TX packets 193512123 bytes 107459762227 (100.0 GiB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
br1: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500
inet 192.168.19.254 netmask 255.255.255.0 broadcast 192.168.19.255
inet6 fe80::225:90ff:fe2e:d8a9 prefixlen 64 scopeid 0x20<link>
ether 00:25:90:2e:d8:a9 txqueuelen 1000 (Ethernet)
RX packets 167220 bytes 52175150 (49.7 MiB)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 174167 bytes 32975397 (31.4 MiB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
br2: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500
inet 192.168.20.254 netmask 255.255.255.0 broadcast 192.168.20.255
inet6 fe80::221:91ff:fed6:daa8 prefixlen 64 scopeid 0x20<link>
ether 00:21:91:d6:da:a8 txqueuelen 1000 (Ethernet)
RX packets 145303 bytes 43515865 (41.4 MiB)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 132665 bytes 20911054 (19.9 MiB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
enp1s4: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500
inet6 fe80::221:91ff:fed6:daa8 prefixlen 64 scopeid 0x20<link>
ether 00:21:91:d6:da:a8 txqueuelen 1000 (Ethernet)
RX packets 2503746 bytes 1017776995 (970.6 MiB)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 2471034 bytes 991294789 (945.3 MiB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
enp5s0f0: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500
inet6 fe80::225:90ff:fe2e:d8a8 prefixlen 64 scopeid 0x20<link>
ether 00:25:90:2e:d8:a8 txqueuelen 1000 (Ethernet)
RX packets 869448632 bytes 1087851084640 (1013.1 GiB)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 342604014 bytes 203755604899 (189.7 GiB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
device memory 0xfafe0000-faffffff
enp5s0f1: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500
inet6 fe80::225:90ff:fe2e:d8a9 prefixlen 64 scopeid 0x20<link>
ether 00:25:90:2e:d8:a9 txqueuelen 1000 (Ethernet)
RX packets 21206229 bytes 6500554675 (6.0 GiB)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 20805805 bytes 6408524379 (5.9 GiB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
device memory 0xfaf60000-faf7ffff
lo: flags=73<UP,LOOPBACK,RUNNING> mtu 65536
inet 127.0.0.1 netmask 255.0.0.0
inet6 ::1 prefixlen 128 scopeid 0x10<host>
loop txqueuelen 1 (Local Loopback)
RX packets 502370 bytes 78778656 (75.1 MiB)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 502370 bytes 78778656 (75.1 MiB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
virbr0: flags=4099<UP,BROADCAST,MULTICAST> mtu 1500
inet 192.168.122.1 netmask 255.255.255.0 broadcast 192.168.122.255
ether 52:54:00:37:be:7d txqueuelen 1000 (Ethernet)
RX packets 0 bytes 0 (0.0 B)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 0 bytes 0 (0.0 B)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
virbr1: flags=4099<UP,BROADCAST,MULTICAST> mtu 1500
ether 52:54:00:b8:21:24 txqueuelen 1000 (Ethernet)
RX packets 0 bytes 0 (0.0 B)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 0 bytes 0 (0.0 B)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
vnet0: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500
inet6 fe80::fc54:ff:fee2:caae prefixlen 64 scopeid 0x20<link>
ether fe:54:00:e2:ca:ae txqueuelen 1000 (Ethernet)
RX packets 15369361 bytes 45420762336 (42.3 GiB)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 23668906 bytes 8045283799 (7.4 GiB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
vnet1: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500
inet6 fe80::fc54:ff:fe75:4502 prefixlen 64 scopeid 0x20<link>
ether fe:54:00:75:45:02 txqueuelen 1000 (Ethernet)
RX packets 65372413 bytes 92323003967 (85.9 GiB)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 88528850 bytes 15240358919 (14.1 GiB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
vnet2: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500
inet6 fe80::fc54:ff:fe00:761d prefixlen 64 scopeid 0x20<link>
ether fe:54:00:00:76:1d txqueuelen 1000 (Ethernet)
RX packets 20630909 bytes 6375500628 (5.9 GiB)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 21037136 bytes 6445910789 (6.0 GiB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
vnet3: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500
inet6 fe80::fc54:ff:fec3:35e2 prefixlen 64 scopeid 0x20<link>
ether fe:54:00:c3:35:e2 txqueuelen 1000 (Ethernet)
RX packets 2338278 bytes 970377345 (925.4 MiB)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 2359253 bytes 972272478 (927.2 MiB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
vnet4: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500
inet6 fe80::fc54:ff:fefd:b505 prefixlen 64 scopeid 0x20<link>
ether fe:54:00:fd:b5:05 txqueuelen 1000 (Ethernet)
RX packets 112 bytes 5016 (4.8 KiB)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 8480 bytes 614444 (600.0 KiB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
主机 IP 地址
# ip a
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN qlen 1
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: enp1s4: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast master br2 state UP qlen 1000
link/ether 00:21:91:d6:da:a8 brd ff:ff:ff:ff:ff:ff
inet6 fe80::221:91ff:fed6:daa8/64 scope link
valid_lft forever preferred_lft forever
3: enp5s0f0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc mq master br0 state UP qlen 1000
link/ether 00:25:90:2e:d8:a8 brd ff:ff:ff:ff:ff:ff
inet6 fe80::225:90ff:fe2e:d8a8/64 scope link
valid_lft forever preferred_lft forever
4: enp5s0f1: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc mq master br1 state UP qlen 1000
link/ether 00:25:90:2e:d8:a9 brd ff:ff:ff:ff:ff:ff
inet6 fe80::225:90ff:fe2e:d8a9/64 scope link
valid_lft forever preferred_lft forever
5: br2: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP qlen 1000
link/ether 00:21:91:d6:da:a8 brd ff:ff:ff:ff:ff:ff
inet 192.168.20.254/24 brd 192.168.20.255 scope global br2
valid_lft forever preferred_lft forever
inet6 fe80::221:91ff:fed6:daa8/64 scope link
valid_lft forever preferred_lft forever
6: br0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP qlen 1000
link/ether 00:25:90:2e:d8:a8 brd ff:ff:ff:ff:ff:ff
inet *.*.16.44/24 brd *.*.16.255 scope global br0
valid_lft forever preferred_lft forever
inet 192.168.5.27/24 brd 192.168.5.255 scope global dynamic br0
valid_lft 227543sec preferred_lft 227543sec
inet6 fe80::225:90ff:fe2e:d8a8/64 scope link
valid_lft forever preferred_lft forever
7: br1: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UP qlen 1000
link/ether 00:25:90:2e:d8:a9 brd ff:ff:ff:ff:ff:ff
inet 192.168.19.254/24 brd 192.168.19.255 scope global br1
valid_lft forever preferred_lft forever
inet6 fe80::225:90ff:fe2e:d8a9/64 scope link
valid_lft forever preferred_lft forever
8: virbr1: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc noqueue state DOWN qlen 1000
link/ether 52:54:00:b8:21:24 brd ff:ff:ff:ff:ff:ff
9: virbr1-nic: <BROADCAST,MULTICAST> mtu 1500 qdisc pfifo_fast master virbr1 state DOWN qlen 1000
link/ether 52:54:00:b8:21:24 brd ff:ff:ff:ff:ff:ff
10: virbr0: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc noqueue state DOWN qlen 1000
link/ether 52:54:00:37:be:7d 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
11: virbr0-nic: <BROADCAST,MULTICAST> mtu 1500 qdisc pfifo_fast master virbr0 state DOWN qlen 1000
link/ether 52:54:00:37:be:7d brd ff:ff:ff:ff:ff:ff
16: vnet1: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast master br0 state UNKNOWN qlen 1000
link/ether fe:54:00:75:45:02 brd ff:ff:ff:ff:ff:ff
inet6 fe80::fc54:ff:fe75:4502/64 scope link
valid_lft forever preferred_lft forever
17: vnet2: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast master br1 state UNKNOWN qlen 1000
link/ether fe:54:00:00:76:1d brd ff:ff:ff:ff:ff:ff
inet6 fe80::fc54:ff:fe00:761d/64 scope link
valid_lft forever preferred_lft forever
18: vnet3: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast master br2 state UNKNOWN qlen 1000
link/ether fe:54:00:c3:35:e2 brd ff:ff:ff:ff:ff:ff
inet6 fe80::fc54:ff:fec3:35e2/64 scope link
valid_lft forever preferred_lft forever
30: vnet0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast master br0 state UNKNOWN qlen 1000
link/ether fe:54:00:e2:ca:ae brd ff:ff:ff:ff:ff:ff
inet6 fe80::fc54:ff:fee2:caae/64 scope link
valid_lft forever preferred_lft forever
48: vnet4: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast master br0 state UNKNOWN qlen 1000
link/ether fe:54:00:fd:b5:05 brd ff:ff:ff:ff:ff:ff
inet6 fe80::fc54:ff:fefd:b505/64 scope link
valid_lft forever preferred_lft forever
HOST 路由
# route
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface
default cc4-gw.colocall 0.0.0.0 UG 0 0 0 br0
62.*.*.0 0.0.0.0 255.255.255.0 U 0 0 0 br0
link-local 0.0.0.0 255.255.0.0 U 1005 0 0 br2
link-local 0.0.0.0 255.255.0.0 U 1006 0 0 br0
link-local 0.0.0.0 255.255.0.0 U 1007 0 0 br1
192.168.5.0 0.0.0.0 255.255.255.0 U 0 0 0 br0
192.168.19.0 0.0.0.0 255.255.255.0 U 0 0 0 br1
192.168.20.0 0.0.0.0 255.255.255.0 U 0 0 0 br2
192.168.122.0 0.0.0.0 255.255.255.0 U 0 0 0 virbr0
主机 brctl 显示
# brctl show
bridge name bridge id STP enabled interfaces
br0 8000.0025902ed8a8 no enp5s0f0
vnet0
vnet1
vnet4
br1 8000.0025902ed8a9 no enp5s0f1
vnet2
br2 8000.002191d6daa8 no enp1s4
vnet3
virbr0 8000.52540037be7d yes virbr0-nic
virbr1 8000.525400b82124 yes virbr1-nic
HOST ping 访客
# ping 62.*.*.61
PING 62.*.*.61 (62.*.*.61) 56(84) bytes of data.
64 bytes from 62.*.*.61: icmp_seq=1 ttl=64 time=0.406 ms
64 bytes from 62.*.*.61: icmp_seq=2 ttl=64 time=0.496 ms
64 bytes from 62.*.*.61: icmp_seq=3 ttl=64 time=0.371 ms
^C
--- 62.*.*.61 ping statistics ---
3 packets transmitted, 3 received, 0% packet loss, time 2000ms
rtt min/avg/max/mdev = 0.371/0.424/0.496/0.055 ms
主机 KVM 网络设置
<interface type='bridge'>
<mac address='52:54:00:fd:b5:05'/>
<source bridge='br0'/>
<model type='virtio'/>
<address type='pci' domain='0x0000' bus='0x00' slot='0x03' function='0x0'/>
</interface>
访客 ifconfig
$ ifconfig
ens3 Link encap:Ethernet HWaddr 52:54:00:fd:b5:05
inet addr:62.*.*.61 Bcast:62.*.*.255 Mask:255.255.255.0
inet6 addr: fe80::5054:ff:fefd:b505/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:11209 errors:0 dropped:5 overruns:0 frame:0
TX packets:157 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:815753 (815.7 KB) TX bytes:11211 (11.2 KB)
lo Link encap:Local Loopback
inet addr:127.0.0.1 Mask:255.0.0.0
inet6 addr: ::1/128 Scope:Host
UP LOOPBACK RUNNING MTU:65536 Metric:1
RX packets:9989 errors:0 dropped:0 overruns:0 frame:0
TX packets:9989 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1
RX bytes:742656 (742.6 KB) TX bytes:742656 (742.6 KB)
GUEST ip a
$ ip a
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1
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: ens3: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP group default qlen 1000
link/ether 52:54:00:fd:b5:05 brd ff:ff:ff:ff:ff:ff
inet 62.*.*.61/24 brd 62.*.*.255 scope global ens3
valid_lft forever preferred_lft forever
inet6 fe80::5054:ff:fefd:b505/64 scope link
valid_lft forever preferred_lft forever
客人路线
$ route
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface
default 62.*.*.2 0.0.0.0 UG 0 0 0 ens3
localnet * 255.255.255.0 U 0 0 0 ens3
访客 ping 主机
$ ping 62.*.*.44
PING 62.*.*.44 (62.*.*.44) 56(84) bytes of data.
64 bytes from 62.*.*.44: icmp_seq=1 ttl=64 time=0.324 ms
64 bytes from 62.*.*.44: icmp_seq=2 ttl=64 time=0.290 ms
^C
--- 62.*.*.44 ping statistics ---
2 packets transmitted, 2 received, 0% packet loss, time 999ms
rtt min/avg/max/mdev = 0.290/0.307/0.324/0.017 ms
GUEST ping 该 HOST 上的其他 GUEST
$ ping 62.*.*.42
PING 62.*.*.42 (62.*.*.42) 56(84) bytes of data.
64 bytes from 62.*.*.42: icmp_seq=1 ttl=64 time=1.21 ms
64 bytes from 62.*.*.42: icmp_seq=2 ttl=64 time=0.635 ms
^C
--- 62.*.*.42 ping statistics ---
2 packets transmitted, 2 received, 0% packet loss, time 1001ms
rtt min/avg/max/mdev = 0.635/0.927/1.219/0.292 ms
$ ping 62.*.*.17
PING 62.*.*.17 (62.*.*.17) 56(84) bytes of data.
64 bytes from 62.*.*.17: icmp_seq=1 ttl=64 time=1.15 ms
64 bytes from 62.*.*.17: icmp_seq=2 ttl=64 time=0.744 ms
^C
--- 62.*.*.17 ping statistics ---
2 packets transmitted, 2 received, 0% packet loss, time 1001ms
rtt min/avg/max/mdev = 0.744/0.947/1.150/0.203 ms
GUEST ping 到 8.8.8.8
$ ping 8.8.8.8
PING 8.8.8.8 (8.8.8.8) 56(84) bytes of data.
From 62.*.*.61 icmp_seq=1 Destination Host Unreachable
From 62.*.*.61 icmp_seq=2 Destination Host Unreachable
From 62.*.*.61 icmp_seq=3 Destination Host Unreachable
^C
--- 8.8.8.8 ping statistics ---
4 packets transmitted, 0 received, +3 errors, 100% packet loss, time 3016ms pipe 3
访客 /etc/network/interfaces
$ tail -n50 /etc/network/interfaces
# This file describes the network interfaces available on your system
# and how to activate them. For more information, see interfaces(5).
source /etc/network/interfaces.d/*
# The loopback network interface
auto lo
iface lo inet loopback
# The primary network interface
auto ens3
iface ens3 inet static
address 62.*.*.61
netmask 255.255.255.0
# network 62.*.*.0
broadcast 62.*.*.255
gateway 62.*.*.2
# dns-* options are implemented by the resolvconf package, if installed
dns-nameservers 8.8.8.8 62.149.2.52 62.149.2.60
访客 iptables
# iptables -L
Chain INPUT (policy ACCEPT)
target prot opt source destination
Chain FORWARD (policy ACCEPT)
target prot opt source destination
Chain OUTPUT (policy ACCEPT)
target prot opt source destination
我很困惑，不知道我需要做什么（（（
答案1
是啊！我找到了解决这个问题的方法：我只需要建立新的 Guest 关系网络。然后一切就开始正常工作了！