LAN - help me understand something

[Fr4nt1s3k]

Hello,
I am not really sure what I have done, but the LAN is finally working.

The first picture describes what the configuration was before and the second describes current situation.

I have 1 satellite dish, which connects to a Ubiquiti POE-24-24W device (the little box), which now also connects to the new switch I bought (TP-LINK TL-SF1005D). From this switch, I have ethernet cables to multiple computers.

 

Now, here comes my confusion.
When I used "arp -a" command to find devices at my network, I found the 2 currently connected computers:
192.168.1.7

192.168.1.10

and also this mysterious address:
192.168.1.254

 

I previously thought the little box acted as a router, but it's simply a power supply / protection for my satellite dish, right? So what is this mysterious address? Could it be the switch itself? 

 

If I set up the network with subnet mask 255.255.0.0 and default gateway 192.168.0.0, the devices could communicate between each other, but not use the internet. If I set up subnet mask 255.255.255.0 and default gateway 192.168.1.254, the devices could both communicate in LAN and use the internet too!
I didn't know I could do this just with a switch.

 

Sorry to make this long, but I have one more question...

Some time ago, I asked my ISP to give me my own public IP address 62.???.???.?21 which will be routed to 192.168.1.7. I did this because some of my games had multiplayer issues with NAT transferal, port forwarding etc.. Will it still work in this current configuration with a switch?

[Fr4nt1s3k]

And one more thing, what does default gateway of 192.168.0.0 mean?
Default gateway should be a physical device, yet this is not, right?

[Tzomb1e]

My first comment here is that 192.168.0.0 is not a usable address for a device on your network...which is why your devices have LAN access, but no WAN access.  The devices can send their PDUs to the switch, but the switch doesn't know where to send data for different subnets.  192.168.0.254 is what your default gateway should be set to for your configuration, since that appears to be your router (based on the fact that your devices have WAN access when this is configured).  The Ubiquiti POE-24-24W is just a power injector.  It uses Power-Over-Ethernet to power a device connected to the "Out" port and does not provide any kind of routing or switching, so it should not have any IP assigned to it.  Have you tried to login to 192.168.0.254 to see if you get any kind of GUI?  Based on your information, I am guessing the satellite has some sort of router built into it, or there is another device connected between the switch and the satellite that is not in your diagram (unless one of the other devices on your LAN has something installed that is acting as a router...which would be odd).  As for your public IP hitting 192.168.1.7, you would have to setup port forwarding on your router (default gateway) to send traffic destined for specific ports to that device.  Not sure if any of that helps or not...

[Mikensan]

Are you sure it's a satellite dish and not a microwave dish? I've never heard of a satellite dish using PoE... Since your injector is Ubiquiti, I'd safely assume it is a ubiquiti dish... Whoever controls the remote point, controls .254.

https://www.ubnt.com/products/#airfiber - one of these probably.

 

You have to have a gateway to access the internet, a device to route traffic (router/gateway) outside your LAN. I'm guessing whatever is at the other end of that dish is where .254 resides. Your POE injector and switch are not gateways.

 

255.255.0.0 is a large spectrum of IP addresses, and the only reason it worked was because you specified a proper gateway (192.168.1.254). I'm not sure why you tried using that subnet, but dont complicate it. Stick with a gateway of 192.168.1.254 and a subnet of 255.255.255.0..

 

I'm surprised you aren't using DHCP, I would assume .254 would be handing out IP addresses.

[Mikensan]

**Also, you are likely still behind a NAT. If a proper ISP issues you an IP address, it is up to you to either configure your firewall to 1:1 NAT, or configure the computer's IP address directly to "62.???.???.?21" instead of 192.168.1.7. Neither of which seem like the case.

***Also static IP addresses cost a good bit of change now adays.

 

Is your ISP some local guy in the neighborhood by chance?

[Alex Atkin UK]

Not using DHCP could be because they are connecting all devices directly and their ISP may only issue a single IP address, expecting you to use a router to share it.

 

Its not a great setup, as with using a private IP address then anything like gaming is likely to not work that well, if at all.

Would be interesting to see what would happen if you WERE using a router, or just connect a single client into the dish to see what IP address it gets from DHCP.