I have had a number of occasions lately where a virtual "NAT" network (such as default) has stopped working. I have attempted to stop and then restart the network from the "network details" but the only thing that seems to work is to restart all of the virtual guests which use that network. I don't believe that I should have to do that. Is there some command which will "fix" things? I have had this happen to me a number of times but I am currently uncertain of the cause. Anyone know what is going on? I am not going to bugzilla this until. I do know one way to cause the problem. Disable the network in a virtual machine. Then using virt-manager's connection details menu, stop that (default) network ... then start it up again. Everything sort-of looks ok but it is not. Go back to the virtual machine and re-enable the previously disable network. Nope ... cannot connect. Start another virtual machine which uses that network and it works fine. In the "real world", I can disable a network, then remove a cable, connect the cable back up, re-enable the network and everything works. BTW, NetworkManager is used in all cases. Any ideas? Gene
On 09/03/2012 11:45 AM, Gene Czarcinski wrote:> I have had a number of occasions lately where a virtual "NAT" network > (such as default) has stopped working. I have attempted to stop and > then restart the network from the "network details" but the only thing > that seems to work is to restart all of the virtual guests which use > that network. I don't believe that I should have to do that. Is > there some command which will "fix" things? > > I have had this happen to me a number of times but I am currently > uncertain of the cause. Anyone know what is going on? I am not going > to bugzilla this until. > > I do know one way to cause the problem. Disable the network in a > virtual machine. Then using virt-manager's connection details menu, > stop that (default) network ... then start it up again. Everything > sort-of looks ok but it is not. Go back to the virtual machine and > re-enable the previously disable network. Nope ... cannot connect. > Start another virtual machine which uses that network and it works fine. > > In the "real world", I can disable a network, then remove a cable, > connect the cable back up, re-enable the network and everything works. > > BTW, NetworkManager is used in all cases. > > Any ideas? >I hate it when I answer my own questions! OK, to get that virtual going again ... remove the NIC from the systems configuration, then add a NIC back making sure you keep the same MAC address ... now it works. Shouldn't there be a better way? Gene
hi,all
I am using virDomainInterfaceStats to monitor the network flow of VM. But
there is some strange things.
the description of vnet in xml is:
<interface type='bridge'>
<mac address='00:16:3e:5d:aa:a8'/>
<source bridge='br0'/>
<target dev='vnet0'/>
<model type='virtio'/>
<address type='pci' domain='0x0000' bus='0x00'
slot='0x03' function='0x0'/>
</interface>
but when I call virDomainInterfaceStats to get network flow from vnet0, I
get some wrong data:
rx: 139972719907412 tx:7311107385599290735
after 2 seconds, I call it again and I get:
rx: 31 tx:7311107385599290735
another 2 seconds:
rx:155 tx:7311107385599290735
and...
rx:110 tx:7311107385599290735
(rx:receive, tx:transmit)
what do these data mean? Why there is no difference in tx at all? And why
the difference in rx is so weird?
Many thanks!
regards
zhangzhang
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