qemu-kvm / virsh：使用桥接networking时没有networking连接

我遇到了通过libvirt / qemu-kvm执行虚拟化的问题，其中我的桥接networking设置似乎没有正常工作。 我已经按照我可以find的每一个教程，并花了几个小时，通过论坛，但目前无济于事。

主机和来宾都使用Centos6。

这是主机的设置：

[root@node2 ~]# ifconfig -a bridge0 Link encap:Ethernet HWaddr BC:30:5B:E8:C0:4F inet addr:10.59.190.253 Bcast:10.59.190.255 Mask:255.255.255.0 inet6 addr: fe80::be30:5bff:fee8:c04f/64 Scope:Link UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets:5315 errors:0 dropped:0 overruns:0 frame:0 TX packets:3350 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:0 RX bytes:316961 (309.5 KiB) TX bytes:3943630 (3.7 MiB) eth0 Link encap:Ethernet HWaddr BC:30:5B:E8:C0:4F inet6 addr: fe80::be30:5bff:fee8:c04f/64 Scope:Link UP BROADCAST RUNNING PROMISC MULTICAST MTU:1500 Metric:1 RX packets:5286 errors:0 dropped:0 overruns:0 frame:0 TX packets:5325 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:409939 (400.3 KiB) TX bytes:4095006 (3.9 MiB) Interrupt:16 Memory:c0000000-c0012800 eth1 Link encap:Ethernet HWaddr BC:30:5B:E8:C0:50 UP BROADCAST MULTICAST MTU:1500 Metric:1 RX packets:0 errors:0 dropped:0 overruns:0 frame:0 TX packets:0 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:0 (0.0 b) TX bytes:0 (0.0 b) Interrupt:17 Memory:c2000000-c2012800 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:16436 Metric:1 RX packets:28 errors:0 dropped:0 overruns:0 frame:0 TX packets:28 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:0 RX bytes:2832 (2.7 KiB) TX bytes:2832 (2.7 KiB) sit0 Link encap:IPv6-in-IPv4 NOARP MTU:1480 Metric:1 RX packets:0 errors:0 dropped:0 overruns:0 frame:0 TX packets:0 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:0 RX bytes:0 (0.0 b) TX bytes:0 (0.0 b) vnet0 Link encap:Ethernet HWaddr FE:54:00:3A:C5:C9 inet6 addr: fe80::fc54:ff:fe3a:c5c9/64 Scope:Link UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets:0 errors:0 dropped:0 overruns:0 frame:0 TX packets:492 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:500 RX bytes:0 (0.0 b) TX bytes:29516 (28.8 KiB) 

我有两个物理适配器，eth0和eth1。 eth1目前已拔出，并未在此设置中使用。 eth0桥接到bridge0。 bridge0使用DHCP来获取其networkingconfiguration。 适配器使用以下configuration：

• 将虚拟机从虚拟机迁移到物理服务器
• 是否有testing，看看目前是否在Linux会话中启用硬件虚拟化（vmx / svm）？
• 如何find虚拟化性能瓶颈？
• 桌面供应小型Linux软件开发团队
• 潜在的VMWare 5.1容错缺陷/问题？

 [root@node2 network-scripts]# cat ifcfg-eth0 DEVICE="eth0" NM_CONTROLLED="no" ONBOOT=yes HWADDR=BC:30:5B:E8:C0:4F BRIDGE=bridge0 [root@node2 network-scripts]# cat ifcfg-bridge0 DEVICE=bridge0 ONBOOT=yes TYPE=Bridge BOOTPROTO=dhcp DELAY=0 NM_CONTROLLED=no 

…和iptables设置如下：

 [root@node2 network-scripts]# iptables --list-rules -P INPUT ACCEPT -P FORWARD ACCEPT -P OUTPUT ACCEPT -A INPUT -m state --state RELATED,ESTABLISHED -j ACCEPT -A INPUT -p icmp -j ACCEPT -A INPUT -i lo -j ACCEPT -A INPUT -p tcp -m state --state NEW -m tcp --dport 22 -j ACCEPT -A INPUT -p tcp -m state --state NEW -m tcp --dport 5900 -j ACCEPT -A INPUT -j REJECT --reject-with icmp-host-prohibited -A FORWARD -m physdev --physdev-is-bridged -j ACCEPT -A FORWARD -m physdev --physdev-is-bridged -j ACCEPT -A FORWARD -j REJECT --reject-with icmp-host-prohibited 

所以，这是成立的。 然后，我使用以下命令来创build并安装Centos6访客映像：

 virt-install --name=centos-bridge-test --disk path=/var/lib/libvirt/images/centos6-minimal,size=5 --vnc --ram=512 --cdrom=/var/lib/libvirt/images/CentOS-6.0-x86_64-minimal.iso --vnclisten=0.0.0.0 -b bridge0 

我的理解是，这种设置应该足以使桥接networking“正常工作”，但是，当我使用virsh命令（ virsh start centos-bridge-test ）启动guest 虚拟机时，它没有networking连接。

这是一个libvirt域的xml转储：

 [root@node2 network-scripts]# virsh dumpxml centos-bridge-test <domain type='kvm' id='7'> <name>centos-bridge-test</name> <uuid>5d611267-2feb-c6f7-7a48-29f9695a4a75</uuid> <memory>524288</memory> <currentMemory>524288</currentMemory> <vcpu>1</vcpu> <os> <type arch='x86_64' machine='rhel6.0.0'>hvm</type> <boot dev='hd'/> </os> <features> <acpi/> <apic/> <pae/> </features> <clock offset='utc'/> <on_poweroff>destroy</on_poweroff> <on_reboot>restart</on_reboot> <on_crash>restart</on_crash> <devices> <emulator>/usr/libexec/qemu-kvm</emulator> <disk type='file' device='disk'> <driver name='qemu' type='raw' cache='none'/> <source file='/var/lib/libvirt/images/centos6-minimal'/> <target dev='hda' bus='ide'/> <alias name='ide0-0-0'/> <address type='drive' controller='0' bus='0' unit='0'/> </disk> <disk type='block' device='cdrom'> <driver name='qemu' type='raw'/> <target dev='hdc' bus='ide'/> <readonly/> <alias name='ide0-1-0'/> <address type='drive' controller='0' bus='1' unit='0'/> </disk> <controller type='ide' index='0'> <alias name='ide0'/> <address type='pci' domain='0x0000' bus='0x00' slot='0x01' function='0x1'/> </controller> <interface type='bridge'> <mac address='52:54:00:3a:c5:c9'/> <source bridge='bridge0'/> <target dev='vnet0'/> <alias name='net0'/> <address type='pci' domain='0x0000' bus='0x00' slot='0x03' function='0x0'/> </interface> <serial type='pty'> <source path='/dev/pts/1'/> <target port='0'/> <alias name='serial0'/> </serial> <console type='pty' tty='/dev/pts/1'> <source path='/dev/pts/1'/> <target port='0'/> <alias name='serial0'/> </console> <input type='mouse' bus='ps2'/> <graphics type='vnc' port='5900' autoport='yes' listen='0.0.0.0' keymap='en-gb'/> <video> <model type='cirrus' vram='9216' heads='1'/> <alias name='video0'/> <address type='pci' domain='0x0000' bus='0x00' slot='0x02' function='0x0'/> </video> <memballoon model='virtio'> <alias name='balloon0'/> <address type='pci' domain='0x0000' bus='0x00' slot='0x04' function='0x0'/> </memballoon> </devices> <seclabel type='dynamic' model='selinux'> <label>system_u:system_r:svirt_t:s0:c384,c608</label> <imagelabel>system_u:object_r:svirt_image_t:s0:c384,c608</imagelabel> </seclabel> </domain> 

界面似乎设置正确（从看libvirt文档）。

所以，每当我启动客人时，就没有networking连接。

 [root@localhost ~]# ifconfig -a eth0 Link encap:Ehternet HWaddr 52:54:00:3A:C5:C9 BROADCAST MULTICAST MTU:1500 Metric:1 RX packets:0 errors:0 dropped:0 overruns:0 frame:0 TX packets:0 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:0 (0.0 b) TX bytes:0 (0.0 b) Interrupt:10 Base address:0x6000 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:16436 Metric:1 RX packets:0 errors:0 dropped:0 overruns:0 frame:0 TX packets:0 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:0 RX bytes:0 (0.0 b) TX bytes:0 (0.0 b) 

编辑：请注意，eth0不在这里，所以我一直在运行ifup eth0来得到适配器来，然后给出以下输出：

 [root@localhost ~]# ifconfig -a eth0 Link encap:Ehternet HWaddr 52:54:00:3A:C5:C9 inet6 addr: fe80::5054:ff:fe3a:c5c9/64 Scope:Link UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets65 errors:0 dropped:0 overruns:0 frame:0 TX packets:5 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:3896 (3.8 KiB) TX bytes:398 (398.0 b) 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:16436 Metric:1 RX packets:0 errors:0 dropped:0 overruns:0 frame:0 TX packets:0 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:0 RX bytes:0 (0.0 b) TX bytes:0 (0.0 b) 

…当我尝试访问networking的内部或外部地址，我得到这个：

 [root@localhost ~]# ping 10.59.190.253 connect: Network is unreachable [root@localhost ~]# ping www.google.com ping: unknown host www.google.com [root@localhost ~]# ping 173.194.66.99 connect: Network is unreachable 

附加信息：以下是对于这个问题的意见所要求的一些额外的信息。 这些命令是在主机正在运行的情况下运行的：

 [root@node2 network-scripts]# brctl show bridge name bridge id STP enabled interfaces bridge0 8000.bc305be8c04f no eth0 vnet0 [root@node2 network-scripts]# ps -ef | grep qemu qemu 1597 1 0 11:28 ? 00:00:25 /usr/libexec/qemu-kvm -S -M rhel6.0.0 -enable-kvm -m 512 -smp 1,sockets=1,cores=1,threads=1 -name centos-bridge-test -uuid 5d611267-2feb-c6f7-7a48-29f9695a4a75 -nodefconfig -nodefaults -chardev socket,id=monitor,path=/var/lib/libvirt/qemu/centos-bridge-test.monitor,server,nowait -mon chardev=monitor,mode=control -rtc base=utc -boot c -drive file=/var/lib/libvirt/images/centos6-minimal,if=none,id=drive-ide0-0-0,boot=on,format=raw,cache=none -device ide-drive,bus=ide.0,unit=0,drive=drive-ide0-0-0,id=ide0-0-0 -drive if=none,media=cdrom,id=drive-ide0-1-0,readonly=on,format=raw -device ide-drive,bus=ide.1,unit=0,drive=drive-ide0-1-0,id=ide0-1-0 -netdev tap,fd=20,id=hostnet0 -device rtl8139,netdev=hostnet0,id=net0,mac=52:54:00:3a:c5:c9,bus=pci.0,addr=0x3 -chardev pty,id=serial0 -device isa-serial,chardev=serial0 -usb -vnc 0.0.0.0:0 -k en-gb -vga cirrus -device virtio-balloon-pci,id=balloon0,bus=pci.0,addr=0x4 root 2815 32057 0 14:31 pts/0 00:00:00 grep qemu 

我非常感谢现在的帮助！ 如果您需要我提供任何进一步的configuration等，请让我知道。

编辑：我使用最小安装的Centos6，所以我没有安装任何窗口pipe理器，所以我试图通过virsh和virsh-install做所有的事情，并且想尽量避免使用virsh-manager。 谢谢。