Help regarding subnet configuration

[Raraolalala]

Hi, I figured I should learn networking since it might be helpful later on and I'm now trying to learn how to properly configure stuff using subnets.

The reason why I'm asking is basically that I don't have the equipment to try things out on my own.
Let's imagine the following:
I have two routers, R1 and R2. R2 has an internet connection.
Connected to these two routers are clients that's connected to two different subnets, S1 on R1 and S2 on R2. How do I configure this so that the clients on different subnets have access to each other? While all of them having internet access as well.

Thanks in advance

Btw, if you could, explain it like I'm braindead cause when it comes to this, I am.

 

[McHenryB]

This sounds suspiciously like a homework question.

 

[Raraolalala]

I suppose it does. I wouldn't mind if someone would point me in the right direction regarding information for dummies. I understand the general concept, I think. But I'm not as good theoretically with computers as I am practically, I usually learn by doing not learn by reading.
I've always done router -> switch. Which removes the need of using several subnets. Why would you use subnets if they can fit into 192.168.0.x.
The difference between A, B and C nets are the amount of clients each net can handle? Yes? No?

The sites I've found uses the 'real' terms. Which is why I wondered if you could explain it like I'm braindead. I don't know binary, is that a must to fully understand subnets?

I really do want to learn.

 

[gbb0330]

you have to create a route between the subnets. google route statement

 

[Raraolalala]

Thank you!

 

[Raraolalala]

If I have only one router that splits one C network into two using the netmask 255.255.128.0, do I really need to set up a routing statement between the two subnets? My first impression is that this is the router's job, it should be 'smart' enough to figure out where traffic should go without it. Granted that it's the only device that controls the two subnets.

 

[gbb0330]

If I have only one router that splits one C network into two using the netmask 255.255.128.0, do I really need to set up a routing statement between the two subnets? My first impression is that this is the router's job, it should be 'smart' enough to figure out where traffic should go without it. Granted that it's the only device that controls the two subnets.

this is a highly theoretical question, so here is a theoretical answer. do you want the router to automatically assume that there needs to be a route between the two networks?
what if the reason you have 2 networks is to keep things separate?
why not just have 1 network instead of hoping for a smart router that creates auto-magic routes between all the networks?

 

[Raraolalala]

Well, I thought that's what routers are for. I thought it could 'manage' on it's own without routing between the two subnets it's "hosting". Or I'm hoping, rather since I don't understand the point of using subnets all in all (in smaller scales that is) and without equipment I can't apply the "learning by doing".
To make the two able to communicate you'd forward the gateway adress to the other gateway's adress?
I have googled. ALOT. I wonder if there are ELI5s on reddit. 😀

 

[abailey]

It depends on your router and how you have it set up. Some routers will automatically build the route for all internal LAN interfaces to talk by default. Some do not. You can also use a routing protocol to help set up routes automatically. All that is way more in depth than can be taught here. You usually use subnets to either: break up a broadcast domain, for security, or for management purposes. A simple example would be a visitor network. Say you wanted a visitor network at your house so visitors could get to the internet but not your computers and stuff on your LAN. You would create a subnet for the visitor network and then have the router not route between the visitor and your LAN so they remain secure from each other. Often times subnets are used in conjunction with VLANs. If you really want to learn about subnets, routing and VLANs I would encourage you to save a little money and get some equipment. You could get a small router and a smart switch for less than $100.
https://www.amazon.com/Ubiquiti-EdgeRouter-Advanced-Gigabit-Ethernet/dp/B00YFJT29C/ref=sr_1_1?s=pc&ie=UTF8&qid=1476456977&sr=1-1&keywords=edgerouter
https://www.amazon.com/gp/product/B00N0OHEMA/ref=oh_aui_search_detailpage?ie=UTF8&psc=1