Network config and diagrams

hi, i have a few beginner questions. we’re running a POC of MaaS on physical hardware. the summary version of our network is that we have a ton of tagged VLANS. physical hardware management nets are segregated from data networks.

is there a reference diagram for how networking is supposed to be configured for MaaS to work? i’ve found individual users’ network diagrams in here but have either missed or haven’t found something similar in the official docs.

this test system has multiple NICs. at the moment, its primary NIC is configured with an IP on the management net. it can route to a data net where hosts will be provisioned from there. it has one IP configured and active.

at the moment, the MaaS DHCP server gets requests from clients on the test data network, but there’s no ACK on either side. the client never secures an IP. at the moment, DHCP helper config is in place at the switch level, but we’d prefer to remove that.

  1. does the MaaS rack controller expect to have a separate network interface or IP defined and active in host level networking to handle traffic in that subnet, or is it enough to be able to route that traffic via its single interface/IP? specifically, does this line in the docs mean that having separate IPs/NICS in each VLAN is a hard requirement?

A rack controller can connect to multiple VLANs, each from a different network interface.

  1. can you update the docs with clearer language around what’s expected for networking to work and/or some reference diagrams?

  2. how have people dealt with complex networks when configuring MaaS management?

thanks in advance. Our environment spans a couple of data centers, involves a couple thousand physical machines and hundreds of virtual machines. MaaS could potentially provision and help us manage all of it if we can get networking solved.

Bumping this. I’m on the OP’s team, our PoC on MaaS is stuck until we can sort out the networking issued we’re experiencing with DHCP. Thanks for any help anyone can provide.

Hey @rockpapergoat!
So to answer your questions:

  1. The rack controller does not necessarily need an interface / IP in a specific VLAN to manage it. It could be argued that that is easier though, as if you plan on deploying uses host interfaces in a VLAN that the rack controller is not part of, you will have to configure a DHCP relay to a VLAN that the rack controller is part of, and ensure the rack controller’s TFTP (UDP port 69) and HTTP (TCP port 5248) services are routable to said VLAN.

  2. We have fairly extensive networking docs found here, is there any particular topic you feel we could expand more on?

  3. As mentioned in the answer to the first question, you can relay DHCP to another VLAN, you also have to address routing TFTP and the rack’s HTTP yourself in this case (i.e make sure the VLANs are not isolated from one another, open the port on the firewall, etc). As far as a separate power network, this is fairly common, and the only requirement is that the power address of a given host is reachable from the rack controller. Alternatively to the relay and routing, you can have a rack controller in each rack (as the name suggests) managing DHCP for each VLAN you desire to use for booting (though you can manage DHCP via the rack controller for non-boot purposes as well).

In your particular case, it sounds like the DHCP helper should receive the broadcast from the deploying host, relay that to the MAAS-managed VLAN (the non-MAAS managed VLAN should be configured within MAAS to be a relay to the MAAS-managed VLAN, in addition to the relay itself being configured). Can you confirm if the OFFER packet reaches the relay (DHCP helper)? It may be that your relay is missing a DHCP option to correctly identify the intended VLAN and forward accordingly.

If you do wish to remove the DHCP helper (or any relay for that matter), you’ll need the rack controller to have an interface in that VLAN.

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Hello,

in regards to your DHCP server make sure you define option 66,67 within each VLAN scope
option 66 = Boot server hostname (your rack controller.)
Option 67 contains the URL of the provisioning file location on your rack controller