Question: I am trying to set up a part of our network as a linux cluster. Since its a little educational for me, I choose using MAAS with JuJu. However there are some questions that boggle my mind and I was hoping that someone could clarify that for me.

The linux cluster I'm about to set up consists of 10 machines. Half of it Dell and the other HP. Both types of machines have a lights-out module (HP=>iLO2, Dell=>DRAC) that support IPMI on a seperate 100Mb NIC. They both support PXE on the first onboard gigabit NIC. I configured the lights out module with a static IP matching the physical layout of the racks and position height. Installing MAAS however didn't ask me on what subnet and vlan the IPMI protocol should be configured. How do I do this?

Also I want only the region controller to be able to contact the internet for package management. The other provisioned nodes should only be allowed to connect to the internet via a proxy on the region controller. So the region controller in my case should be configured with 3 subnets; 1 for internet, 1 for client protocol connectivity and 1 for cluster traffic. The region controller itself should also be a node for JuJu.

Then at last there is the node configuration that should have a sort of basic layout that can be used within JuJu. As far as I could see there is no possibility to set up cluster subnet configuration. Each machine has at least 4 NIC's that I like to assign the different subnets to; 1 for the IPMI traffic, 1 for the PXE boot traffic, 1 for the cluster traffic and 1 for the storage/client network. What I like to do is to bond all these interfaces together as one big trunk and then use VLAN's to separate the traffic **before** provisioning. Then when provisioning a node, MAAS should automagically configure the network interfaces as the layout suggests above.

Maybe what I'm looking for is a advanced configuration tutorial/guide for MAAS and JuJu.

Regards,
Joham

Answer: 
Maybe if you let install of [Juju GUI](https://juju.ubuntu.com/docs/howto-gui-management.html) to provide adequately more what type of network balancing you need then you could find your answer faster. 

[**Using Juju with GUI**](https://juju.ubuntu.com/docs/howto-gui-management.html)

This advanced guides very close to your problem:  

[**MAAS: Cluster Configuration**](http://maas.ubuntu.com/docs/cluster-configuration.html)  

[**Additional Manual Configuration**](http://maas.ubuntu.com/docs/configure.html#installing-additional-clusters)
Meanwhile I have a better understanding of how networking is arranged in maas and its pretty cool. So to answer my own question: 
I recommend against separating IPMI and PXE traffic. Its more efficient to just share the RAC traffic on eth0. All server can boot PXE default on eth0 too. 

Besides, you don't need an extra ethernet port/switch for just the RAC, and no extra cables, so that is less energy consumption, thus good! You can use shared nic for iDRAC 5+ & ILO2+, iDRAC 6 and higher have shared nic failover, but iLO2 doesn't.

The nic interface for PXE traffic is normally selectable in the server boot options. From there you assign the maas cluster controllers network interface. This interface is connected to the machines you like to control on that cluster network. Give them a dynamic range to boot into with DHCP and your a go. In the network tab of the maas webgui menu you will find your first network. You can select if you will, the first interface of each machine on that maas network and create a new maas network to route your other traffic to. 

Thanks for the input!

Regards,
Joham