networking @sh.itjust.works WhyAUsername_1 @lemmy.world 7 mo. ago

Trying to connect two routers

Hi all!

I have 2 ISPs with their own routers.

Router A: 192.168.0.1/24

Router B: 192.168.20.1/24

I have my servers plugged into Router A and all my endpoint and users' devices connected to Router B.

I want users connected to Router B (192.168.20.1/24) to have access to server 192.168.0.90

I thought plugging a LAN cable and connecting Router A and Router B and then defining static routes in both routers would solve the issue.

However, at the first step itself I have an issue. When connecting the routers via a LAN cable, both routers dont get any IP.

I was also referring to this post on superuser. Though Router B is capable of creating subnet and static route, I am not sure if Router A (Archer XR500v) is capable of creating a subnet and/or a static route.

https://superuser.com/questions/1667068/connect-two-routers-with-different-subnet

10 comments

You are going down a road of headaches here. Do you absolutely have to use this hardware to complete this setup? If not please consider getting a dual-wan load-balancing router. Cisco makes a nice one, tp-link has a fairly cheap version too. You can use the provided routers behind a firewall as better wireless AP nodes.
- Yeah, this looks like consumer grade crap. I'm a simple home user, and I've found a lot of value in entry level enterprise gear (Mikrotik router, Ubiquiti AP).
  
  OP, if your org is big enough to need two ISPs, you're big enough to buy enterprise hardware. It doesn't need to be expensive, for example this TP-link router can do up to 3 WANs (~$60 on Amazon) and I use the Mikrotik Hex S (~$70; it can do at least two). Separate your router and AP and you can upgrade each independently as needed. That said, configuration will be more complicated (esp for my Mikrotik, not sure amor TP-Link) since they're designed for power users, but there are lots of good guides online.
Wouldn't it be easier just to put both routers on the same IP range and just set the gateway on the clients to be whichever router you wanted to provide internet access?

You might want to disable DHCP on the non-favoured one.
- This is the way I ended up doing it.
  
  Thanks for pointing me in the right direction. :)
  
  You're welcome!
  
  Happy 2024, and thanks for letting me know.
- Sounds reasonable, basically what I suggested as well.
You have two DHCP servers but can't set a separate IP on one of the interfaces as far as your information goes. You didn't provide the second router model.

That means I would disable the DHCP server on router B and set its IP to a static one in the router A's subnet. This means that you can hand out the gateway A from A via DHCP to clients and have the server set to a static IP with B as a gateway.

This all depends on the configuration options though. If you can set an IP or DHCP client per interface, you could also just do that.
I'm not sure about the point of your setup but let's ignore that :

Create a vlan "servers" on router B, assign a port (WITHOUT vlan tagging) to this vlan, patch a cable between this port and any port on rouer A

Put a static IP address 0.x on router B in this vlan

Enable routing between the default vlan and vlan "servers" on router B .

Configure router A to not distribute this IP address (by setting up a permanent DHCP lease for example)

On all your servers put a static route that says : "192.168.20.0/24 via 192.168.0.x"

If you can setup this route on A, things connected to A will work whether they have the route or not (it's not a big deal but the routing would be assymetrical)

If you can create a VLAN and a route on A, you can create a distinct "interconnect" VLAN and make all of that nice and clean without the extra static routes on the servers.
- Probably a consumer router which can't even VLAN.

You've viewed 10 comments.