Le lundi 20 décembre 2010 à 23:12 -0700, Alex Williamson a écrit : > On Mon, Dec 20, 2010 at 11:07 PM, Eric Dumazet <[email protected]> wrote: > > Le mardi 21 décembre 2010 à 13:53 +0800, Yueyu Lin a écrit : > >> Hello, everyone > >> I just encountered a very strange issue in Ubuntu 10.10 server > >> edition X86 64bits. I just start up my kvm like : > >> kvm -net nic,macaddr=B3:C0:64:AF:73:28,model=virtio -net > >> tap,script=/etc/qemu-ifup,downscript=/etc/qemu-ifdown,ifname=tap2 > >> -enable-kvm -drive file=cassandra.raw,format=raw,aio=native -vnc :2 > >> This Mac address doesn't work at all. No working means the > >> virtual machine just thinks the eth0 is not plugged in. After I > >> changed the MAC address, it works as I expected. > >> Are there any restrictions that I can't use certain MAC > >> addresses?-- > > > > > > Sure > > > > First byte must be even. > > > > B3 is odd, so its not valid. > > > > low order bit is a marker for 'multicast' > > See here for reference: http://en.wikipedia.org/wiki/MAC_address > > Typically also makes sense to set the locally administered bit to > avoid collisions with real devices too.
KVM should warn the user the given MAC address is wrong. ifconfig does : # ifconfig eth3 hw ether F4:CE:46:87:96:CF # ifconfig eth3 hw ether F5:CE:46:87:96:CF SIOCSIFHWADDR: Invalid argument -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
