Messy network, virtualized OpenWrt approach, using OSPF?

Ahoy my friends.
Today i'd like to get rid of all the mess i have on my network.
It's been a while since i have upgraded my server. There are almost 100 virtual machines running on it, and it's a 32 Core 128GB ECC RAM EPYC machine.
My actual router is a dual socket based Westmere system, using 2x Xeon X5650 and 16GB ECC RAM.
The power consumption of my server is around 200W, and of my router 250W.

So i was thinking about moving the cpu intense part onto my server, and using my router for mwan3 load balancing only, and as Management-VLAN gateway as well as default gateway for everything else.

So that's how my network currently looks like. A lot of routers because i got my brother living here, having his own internet connection. So the VLAN 1000 is passed through all routers and floors to his room, using PPPoE. Also he got a router connected to my network, using OpenWRT, in order to establish routes between mine, and his network.
Also my network is growing, and there will be additional routers in the future as well.
Currently i am studying for my CCNP certification, and i would like to implement it's related topics somehow in my network, and maybe get some benefit of it. So i thought i may use OSPF for my home network in this case. This way i could get rid of the power consuming router, and use my old and cheap OpenWRT Banana Pi R1 again, for acting as a gateway only. The cpu intense work, like 10G routing, i would like to move it onto an OpenWRT VM in my server, and connecting my almost 100 virtual machines onto it, using vSwitches as well, instead of spreading all these VLANs accorss my network. This way i could dynamically redistribute the connected routes on my server to the rest of the network in order to be able to access them, without having static routes (That's what i currently have on my machine).

Here how it is meant to be, in my opinion.

So in conclusion, i would like to get rid of my old router, and move the cpu intense stuff onto my server, which has a lot of resources left.
Also i'd like to implement techniques, learned from my CCNP preparations in order to get used to them, and have a little bit of practice and fun.

Is it maybe even better to use different areas, or even stub areas? Maybe in order to provide route summarization for all the 192.168.x.x/24 subnets, for a 192.168.0.0/16 route?

The gateway router should simply provide the default route only, using default-information originate

I am looking forward for some advices in my case! At the moment i got almost 100mbps on broadcast traffic.
Thanks in advance!

Personally I would do lab in gns3/eve-ng and leave home [production] network alone. Home network is usually too simple for CCNP/ospf and should be as simple and stable as possible.

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I don't see any sense to overcomplicate the network with the addition of OSPF. You don't have any loops or multiple paths. All hosts are using the OpenWrt VM as gateway, which then forwards to BananaPi. A couple of static routes will do. Same for the OpenWrt router at the bottom.

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Thanks a lot. I have moved onto it and i'm using my Pi router only as a gateway now, and a bunch of other things as well.
Even though i have moved to OSPF now because a third router was necessary right now, and because of all the different subnets maybe a hundred static routes would be mandatory.
But i got a question now. When creating interfaces for subnets on another router, i got my OSPF interface on LAN zone as well as all the other interfaces. Unfortunately i have to specifiy a default ipv4 and ipv6 gateway manually by typing in the ip of the OSPF interface. Is there a way to do so automatically? Because when i create a WAN Interface, it's being written in automatically as a default gateway for new interfaces. Is there a way to do the same for the OSPF interface which is in LAN zone, but not in WAN zone, to automatically act as default gateway for new interfaces?
Reason for that is, i usually create a bunch of new interfaces and sometimes i forget to manually specifiy the ipv4 default gateway. Furthermore i use DHCP in order to assign IP addresses in my "All ospf routers subnet".
Despite these little issues it's running fine. My third router is now a Cisco 2911, quite powerful, and it was able to form an adjacency with the other routers.
Even though i am looking forward to try to form an OSPF adjaceny over Wireguard to my grandma's network.

hint: aggregate

I am not sure I understand the question. The interface has IP/mask and a gateway if it is upstream to the internet.

That doesn't sound like a good idea.

Thanks a lot for your reply.
Well, i've solved the problem. I have created a new zone, called OSPF and accept,accept,accept to and from LAN zone. Now when i create a new interface, my OSPF interface is automatically configured as default IPv4 interface in all the other ones, without manually specifying it.

Oh yeah, thats a good suggestion, aggregation might solve this problem as well. Maybe i will give it a try.

What problems may occur in case of DHCP assignment in case of the OSPF router subnet?

Why should your whole routing depend on a DHCP server?

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