On 6/10/2014 12:43 PM, Digimer wrote: > On 10/06/14 12:38 PM, Steve Campbell wrote: >> >> On 6/10/2014 12:05 PM, Digimer wrote: >>> On 10/06/14 11:46 AM, Steve Campbell wrote: >>>> >>>> On 6/10/2014 10:46 AM, Digimer wrote: >>>>> On 10/06/14 10:03 AM, Steve Campbell wrote: >>>>>> I had so much trouble putting Centos 6 guest VMs on a Centos 5 host >>>>>> that >>>>>> I finally switched to a Centos 6 host. >>>>>> >>>>>> I've not needed more that test VMs, so I've used Virtual Machine >>>>>> Manager >>>>>> on the old system, which worked pretty well, so I decided to >>>>>> create my >>>>>> first KVM guest machine. I noticed when I created it, I only had the >>>>>> options of NAT for my network interface, so I used that (obvious). >>>>>> >>>>>> Well, after starting the VM, I find I don't have connectivity with >>>>>> that >>>>>> interface. Reading, I find examples where I need to create bridges >>>>>> perhaps. Xen did most of this for me, so it's a little new to me. >>>>>> >>>>>> Can anyone throw me a clue, please? >>>>>> >>>>>> steve campbell >>>>> >>>>> Setting up a bridge is not that hard, and it will give your VMs >>>>> direct >>>>> access to the outside world, and host <-> VM access just fine as >>>>> well. >>>>> >>>>> Here is a link showing how to setup a bridge connected to a bond >>>>> device. Ignore the bond and pretend it is a straight ethX device: >>>>> >>>>> https://alteeve.ca/w/AN!Cluster_Tutorial_2#Configuring_our_Bridge.2C_Bonds_and_Interfaces >>>>> >>>>> >>>>> >>>>> >>>>> >>>> The host has a device named virbr0 that is installed during system >>>> installation. It also has a network device vnet0. There are no >>>> files in >>>> /etc/sysconfig/network-scripts for these. >>>> >>>> Shouldn't I be able to use the virbr0 virtual bridge for this? I've >>>> tried setting up the VM's device with all of the options that is >>>> listed, >>>> but to no avail. >>>> >>>> Should I need to set up another bridge for this? >>>> >>>> And thanks for the link. >>>> >>>> steve >>> >>> virbr0 is created and managed by libvirtd. If you open Virtual Machine >>> Manager, connect to localhost and then double-click on 'localhost', >>> you will see a tab for creating/managing bridges (NAT'ed, generally). >>> I disable 'virbr0' as NAT'ing is generally not what I want. >>> >>> The 'vnetX' devices are dynamically created to link a VM's interface >>> to a bridge. Think of them as virtual network cables. They get created >>> and destroyed as needed. >>> >>> >> Sorry, but I'm confused: >> >> My host server has a real NIC and IP address with a real gateway to the >> outside: >> virtbr0 IP: 192.168.122.1 >> Host IP: 10.0.5.16 >> Gateway IP: 10.0.5.1 >> on eth0 and this works >> >> My VM server has all fake stuff currently: >> Host IP: 10.0.5.17 >> Gateway IP: 10.0.5.1 >> on eth0 and this is like NIC without a cable. >> >> So I need to create a bridge device on both the host and VM (lets say I >> name it br1). I change the eth0 config file on both host and VM to point >> to br1 and give the br1 config file on both host and VM the correct IP. >> But won't this just let the two talk to each other. How will the VM >> server get outside? >> >> steve > > The bridge is created only on the host. Think of the bridge as being > like a virtual switch. When a VM is created, you tell it to connect to > the bridge, similar to how you would plug a physical wire into a real > switch. That provides the link to the network, and then you configure > the virtual server's network just as if it was a real network. > > On the host, you don't set the IP on the ethX device, instead you tell > ethX to connect to the bridge (look at 'bond2' in the link above for > the 'BRIDGE="..."' line). Then you move the host's IP address/config > to the bridge itself (look at the 'vbr2' in the link above). > > If you're still stuck, tell me the IP addresses you want to set in the > host and VM and I'll see if I can bang out a couple sample 'ifcfg-X' > files. > I'm running into some problems with my config files where I get a message that says the network can't determine my interface names. I'll look further, but the IPs above are what I need. 10.0.5.1 is a firewall that NATs the 10.0.5.0/24 network to another outside public firewall. Thanks steve