-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA256 Gao feng @ 12/12/2013 10:18 PM:> I saw there are two bridge br0 and virbr0 in your host. which > bridge the libvirt uses? what's result of #virsh net-list ?well i don't quite understand bridges and their function, i'm kinda just following directions. br0 replaced eth0 though in my interfaces file according to this guide[1] i followed to setup the bridge. i'm pretty sure virbr0 is what libvirt uses.... host$ cat /etc/network/interfaces auto lo iface lo inet loopback auto br0 iface br0 inet static address 67.180.246.122 netmask 255.255.255.248 gateway 67.180.246.121 dns-nameservers 67.180.241.11 67.180.241.12 bridge_ports eth0 bridge_fd 9 bridge_maxage 12 bridge_stp off host$ virsh net-list Name State Autostart - ----------------------------------------- default active yes host$ virsh net-dumpxml default <network> <name>default</name> <uuid>e6d3f97a-5870-8ee7-1d82-64b3434f138b</uuid> <forward mode='nat'/> <bridge name='virbr0' stp='on' delay='0' /> <ip address='192.168.122.1' netmask='255.255.255.0'> <dhcp> <range start='192.168.122.2' end='192.168.122.254' /> </dhcp> </ip> </network> $ 1. https://help.ubuntu.com/12.04/serverguide/network-configuration.html#bridging -----BEGIN PGP SIGNATURE----- iEYEAREIAAYFAlKrx58ACgkQXhfCJNu98qDHhwCguJBus/7kZj+5R2EAYSzSENg8 SFwAoLVCxi6jJQBaUhMl4Ter+Jnvq/rI =4wm8 -----END PGP SIGNATURE-----
On 12/14/2013 10:51 AM, scar wrote:> -----BEGIN PGP SIGNED MESSAGE----- > Hash: SHA256 > > Gao feng @ 12/12/2013 10:18 PM: >> I saw there are two bridge br0 and virbr0 in your host. which >> bridge the libvirt uses? what's result of #virsh net-list ? > > well i don't quite understand bridges and their function, i'm kinda > just following directions. br0 replaced eth0 though in my interfaces > file according to this guide[1] i followed to setup the bridge. i'm > pretty sure virbr0 is what libvirt uses.... > > host$ cat /etc/network/interfaces > auto lo > iface lo inet loopback > > auto br0 > iface br0 inet static > address 67.180.246.122 > netmask 255.255.255.248 > gateway 67.180.246.121 > dns-nameservers 67.180.241.11 67.180.241.12 > bridge_ports eth0 > bridge_fd 9 > bridge_maxage 12 > bridge_stp off >remove this br0 sector from the interfaces file. and restart the network. (remove the bridge br0) I'm not familiar with the configure files in ubuntu, let's use the command. 1, ifconfig eth0 0.0.0.0 2, brctl addif virbr0 eth0 3, ifconfig virbr0 67.180.246.122/29 4，ip route add default via 67.180.246.121 dev virbr0 5, ifconfig eth0 x.x.x.x/29 (in container) 6, ip route add default via 67.180.246.121 dev eth0 (in container) but this will not work when you restart libvirt.> host$ virsh net-list > Name State Autostart > - ----------------------------------------- > default active yes > > host$ virsh net-dumpxml default > <network> > <name>default</name> > <uuid>e6d3f97a-5870-8ee7-1d82-64b3434f138b</uuid> > <forward mode='nat'/> > <bridge name='virbr0' stp='on' delay='0' /> > <ip address='192.168.122.1' netmask='255.255.255.0'> > <dhcp> > <range start='192.168.122.2' end='192.168.122.254' /> > </dhcp> > </ip> > </network> > > $ > > > 1. > https://help.ubuntu.com/12.04/serverguide/network-configuration.html#bridging > -----BEGIN PGP SIGNATURE----- > > iEYEAREIAAYFAlKrx58ACgkQXhfCJNu98qDHhwCguJBus/7kZj+5R2EAYSzSENg8 > SFwAoLVCxi6jJQBaUhMl4Ter+Jnvq/rI > =4wm8 > -----END PGP SIGNATURE----- > > _______________________________________________ > libvirt-users mailing list > libvirt-users@redhat.com > https://www.redhat.com/mailman/listinfo/libvirt-users >
Gao feng @ 12/15/2013 07:47 PM:>> remove this br0 sector from the interfaces file. and restart the network. (remove the bridge br0) >> I'm not familiar with the configure files in ubuntu, >> let's use the command. > >> 1, ifconfig eth0 0.0.0.0 >> 2, brctl addif virbr0 eth0 >> 3, ifconfig virbr0 67.180.246.122/29 >> 4，ip route add default via 67.180.246.121 dev virbr0 >> 5, ifconfig eth0 x.x.x.x/29 (in container) >> 6, ip route add default via 67.180.246.121 dev eth0 (in container) > >> but this will not work when you restart libvirt.hehe well i kinda need something that will work :P also if i take out br0 from interfaces file i'm pretty sure my server will become inaccessible :\
Laine Stump
2013-Dec-20 08:04 UTC
Re: [libvirt-users] assign static external IP to container
On 12/16/2013 04:47 AM, Gao feng wrote:> On 12/14/2013 10:51 AM, scar wrote: >> -----BEGIN PGP SIGNED MESSAGE----- >> Hash: SHA256 >> >> Gao feng @ 12/12/2013 10:18 PM: >>> I saw there are two bridge br0 and virbr0 in your host. which >>> bridge the libvirt uses? what's result of #virsh net-list ? >> well i don't quite understand bridges and their function, i'm kinda >> just following directions. br0 replaced eth0 though in my interfaces >> file according to this guide[1] i followed to setup the bridge. i'm >> pretty sure virbr0 is what libvirt uses.... >> >> host$ cat /etc/network/interfaces >> auto lo >> iface lo inet loopback >> >> auto br0 >> iface br0 inet static >> address 67.180.246.122 >> netmask 255.255.255.248 >> gateway 67.180.246.121 >> dns-nameservers 67.180.241.11 67.180.241.12 >> bridge_ports eth0 >> bridge_fd 9 >> bridge_maxage 12 >> bridge_stp off >> > remove this br0 sector from the interfaces file. and restart the network. (remove the bridge br0) > I'm not familiar with the configure files in ubuntu, > let's use the command. > > 1, ifconfig eth0 0.0.0.0 > 2, brctl addif virbr0 eth0 > 3, ifconfig virbr0 67.180.246.122/29 > 4，ip route add default via 67.180.246.121 dev virbr0 > 5, ifconfig eth0 x.x.x.x/29 (in container) > 6, ip route add default via 67.180.246.121 dev eth0 (in container) > > but this will not work when you restart libvirt.This advice is incorrect and should not be followed! The br0 that he has created is *exactly* what he needs, so he shouldn't remove it from the config. And you should *never* manually mess with the bridges setup by libvirt's virtual networks. What you've done here is modify virbr0 to temporarily appear exactly as he already had br0 setup, and this temporary change will be undone the next time you stop/start libvirt's default network, or restart the host. Sorry for coming in so late on this discussion, but it sounds like the guest (aka "vm") is probably configured to use libvirt's "default" network, which means that it is connected to the bridge "virbr0", and that bridge is *not* directly connected to the physical network - it instead sets up a private network on 192.168.122.0/24 and uses IP masquerading (NAT) to make all the guests appear to the outside world as the host's IP address). You can verify this by looking for the <interface> section in the guest's to see if it looks like this: <interface type='network'> ... <source network='default'/> ... </interface> (also, when configured for DHCP, your guest will get an IP address in the 192.168.122.0/24 range). Since virbr0 has no L2 connection to the physical network - its only connection is via the host's IP routing stack, i.e. L3 - simply changing the IP configuration in the guest just gives you an interface with an IP from the physical net that is effectively disconnected from that network, exactly as you've described. If you want your guest to be connected directly to the physical network, you will need to change the guest's config so that the <interface> section instead looks like this: <interface type='bridge'> ... <source bridge='br0'/> ... </interface> You can make this change by running "virsh edit $guestname" at a root shell prompt (that brings up the guest config in vi, or whatever is set as $EDITOR in root's environment), making the modifications and saving the file. After that, you will need to shutdown the guest completely, then restart it for the changes to take effect. At that time you should be able to modify the guest's network config files (in the guest's own system config) with the secondary static IP address your COLO provider has allocated for you. (Note that, if the COLO has restrictions on MAC address (e.g. Hetzner), then you will need to request a new MAC address to go with the 2nd IP address, and edit the guest config's <interface> section to use that MAC address instead of the one automatically generated by libvirt). TL;DR - put back the config for br0 if you've removed it, then modify the guest's <interface> config to use br0 instead of the default network.