[Users] simple networking?

[noc]

Resend to the list for others to benefit, I hope :-)

Joop


On 27-11-2013 18:18, Ted Miller wrote:
> I am trying to set up a testing network using o-virt, but the
> networking is refusing to cooperate.  I am testing for possible use in
> two different production setups.
>
> My previous experience has been with VMWare.  I have always set up a
> single bridged network on each host.  All my hosts, VMs, and non-VM
> computers were peers on the LAN.  They could all talk to each other,
> and things worked very well.  There was a firewall/gateway that
> provided access to the Internet, and hosts, VMs, and could all
> communicate with the Internet as needed.
>
> o-virt seems to be compartmentalizing things beyond all reason.
That is a way to use oVirt, but the following simple setup should work 
and give you a way to check against your setup.

I have two setups, one at home and one at work. The one at home is a 
setup of 2 hosts and one of those is a hacked up host/engine.
engine/host1: standard fedora19 kde install, static ip (192.168.1.11) 
configured with my NAS (192.168.1.16) as dhcp/dns server and my internet 
router (192.168.1.254) as gateway
Just make sure that NetworkManager is off and that your interfaces are 
not NM managed, network on.
This was a allinone setup but I got a NAS with NFS so I turned my aio 
setup into a engine/host system. It has problems with that but nothing 
network related.

Host2: same as above but without the engine install, ip:192.168.1.22, gw 
192.168.1.254 DNS:192.168.1.16.

How does it all come together?
Well in your case, and mine if I were to start over, start with a static 
network which is NOT managed by NetworkManager. Use either Fedora or 
Centos which ever you more comfortable with and it also depends on 
whether you want to test/use all the features in oVirt. Currently, there 
are a few features not available in Centos because the versions of 
libvirt/kvm/qemu/gluster are too old in Centos.
Install ovirt-engine on your first 'server', probably choose NFS as your 
storage domain, either on your engine server or from somewhere else on 
your network. Make sure its nfs-v3 and not v4!, local default is v4!
Make sure that ip addresses on you network are resolvable, either 
through /etc/hosts or through DNS! Engine-setup will complain if this 
doesn't work, using localhost will not work either!
On the engine server there will be no bridge and nothing will change the 
network config.

Next the first host.
Prepare the host in a similar way you did the engine server. You can 
choose a minimal install of either Centos or Fedora or install a full 
desktop but make sure that ips are static and NOT managed by 
NetworkManager, hostname resolvable, ovirt repo available.

 From the webui add your prepared host and if everything went OK you'll 
see that on that host you will now have a bridge, ovirtmgmt, which acts 
as the primary interface.
Create a VMs and choose ovirtmgmt as a network for its nics, can't 
choose anything else. Either give the VMs a static address or use a dhcp 
server but the VMs should be able to talk to each other, to the host(s), 
the engine and to the internet.

Every host that you add after the first will also has its network turned 
into a bridge, ovirtmgmt, and communication/migration/display/etc will 
take place over this network. One caveat, storage domain mapping is from 
the host to the storage, the engine, if it is NOT the NFS server, 
doesn't have to have access to the storage.

If you have servers with more that 1 nic then you can create additional 
networks using the webui of oVirt and assign these to clusters and to VMs.

If you need vlans to coexist with ovirtmgmt on the same physical nic, I 
think that is possible but haven't tried it myself. In theory you need 
to setup the network first outside of oVirt, including you vlan 
structure and then install ovirt.

Some concepts:
oVirt engine: is just the manager, does 'nothing' related to running VMs 
itself. You can turn it off and all hosts with their VMs will keep 
running. You just can't start new ones, in short manage them.
oVirt host: is the real workhorse and is managed using oVirt-engine. 
Runs VDSM which communicates with engine and starts/manages the VMs on 
the host on behalf of engine.
oVirt node: is a special slimmed down Fedora distro that includes VDSM 
and a small setup so that it can be used as a oVirt host

People tend to mix and match ovirt-host and ovirt-node which makes for 
nice communication problems :-)

If you haven't done so, there is an irc channel, ovirt, on irc.oftc.net 
with helpful people, if they are awake.

Joop
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