Connecting to things locally without router

[Oli1549]

I have a network switch that everything connects to when I remove the router I can no longer connect to anything on the network (Rasp Pi server, printer, Etc) I assume this is because there is no DHCP server.

 

How could I make it so I can connect to my network appliances with no router turned on/connected?

 

 

[LukeSavenije]

you could try to let one pc share a local wired hotspot.

 

you need wifi to work tho

[Oli1549]

2 minutes ago, LukeSavenije said:

you could try to let one pc share a local wired hotspot.

 

you need wifi to work tho

Yeah so if i set my phone to hotspot to my PC, which is what im doing.  how can i share this over the network?

[LukeSavenije]

1 minute ago, Oli1549 said:

Yeah so if i set my phone to hotspot to my PC, which is what im doing.  how can i share this over the network?

in the network settings (control panel) at your network adapter (your hotspot in this case) under share

there you select the ethernet adapter, you connect that to the wan, done

[Oli1549]

1 minute ago, LukeSavenije said:

in the network settings (control panel) at your network adapter (your hotspot in this case) under share

there you select the ethernet adapter, you connect that to the wan, done

is there a way to display the IP addresses given to devices?

 

And will it automatically give a address to a PI?

[LukeSavenije]

2 minutes ago, Oli1549 said:

is there a way to display the IP addresses given to devices?

 

And will it automatically give a address to a PI?

not sure... maybe on the pi itself?

[Oli1549]

2 minutes ago, LukeSavenije said:

not sure... maybe on the pi itself?

Its in my atic, no monitor or keyboard up there, and if i cant work out the IP i cant SSH into it, Same with my unraid server, i really dont want to have to grab a monitor and keyboard, surely theres a easier way?!

 

 

[LukeSavenije]

Just now, Oli1549 said:

Its in my atic, no monitor or keyboard up there, and if i cant work out the IP i cant SSH into it, Same with my unraid server, i really dont want to have to grab a monitor and keyboard, surely theres a easier way?!

 

 

I don't know any... but I'm not a network guru or something, so I'll leave that to someone else...

[buzzinkeegs]

https://smallbusiness.chron.com/ping-ip-addresses-lan-68381.html

[Windows7ge]

This might be annoying down the road but if you setup static IP's on all of the devices this might maintain intercommunication in the absence of the router. I can't guarantee that though.

 

One of the issues when you unplug the router is each systems ARP table won't have build the local network. Each system just has the router and the router holds the table. The Switch will have a Layer 2 table of each device but every system still wants to send to the router.

 

You'd have to build the switches table each time you disconnect the router while having static IP's assigned to the clients. The switch would send out broadcasts upon requests and progressively maintain communication on the network.

 

The main issue here is I don't believe the switch will hold two paths if the router disappears. If the router is plugged in, everything will go through the router. If the router isn't plugged in, everything will be forwarded through the switch but each time you do the the table has to be rebuilt which will result in a temporary network outage.

 

In the enterprise there are setups that have redundant routers with redundant tables where 1 router can be taken down and the other will kick in so the users don't know that anything happened at all.

[Windows7ge]

1 hour ago, Oli1549 said:

is there a way to display the IP addresses given to devices?

 

And will it automatically give a address to a PI?

On a router it will build a list of connected clients with their IP, MAC, and associated name. Assuming DHCP is setup on the Pi and you can remote into it once it receives an IP the router will tell you what address it was given enabling you to do so.

[Oli1549]

4 minutes ago, Windows7ge said:

On a router it will build a list of connected clients with their IP, MAC, and associated name. Assuming DHCP is setup on the Pi and you can remote into it once it receives an IP the router will tell you what address it was given enabling you to do so.

Yeah the IP that it was given by the router has obviously changed because i cant connect to it.

[Oli1549]

33 minutes ago, Windows7ge said:

This might be annoying down the road but if you setup static IP's on all of the devices this might maintain intercommunication in the absence of the router. I can't guarantee that though.

 

One of the issues when you unplug the router is each systems ARP table won't have build the local network. Each system just has the router and the router holds the table. The Switch will have a Layer 2 table of each device but every system still wants to send to the router.

 

You'd have to build the switches table each time you disconnect the router while having static IP's assigned to the clients. The switch would send out broadcasts upon requests and progressively maintain communication on the network.

 

The main issue here is I don't believe the switch will hold two paths if the router disappears. If the router is plugged in, everything will go through the router. If the router isn't plugged in, everything will be forwarded through the switch but each time you do the the table has to be rebuilt which will result in a temporary network outage.

 

In the enterprise there are setups that have redundant routers with redundant tables where 1 router can be taken down and the other will kick in so the users don't know that anything happened at all.

Ok, so, if i literally use a old router, connect that to the switch directly, allow it to do the DHCP and all the fancy stuff, then have the new router connected to the old router, providing internet? so if the internet one goes the only thing lost is an internet connection??

 

Maybe this will work somehow?

[mtz_federico]

Have you tried giving each client a static ip and setting the gateway to one device that has two ethernet ports, one connected to the switch and another connected or disconnected to the router for internet.

[Windows7ge]

10 hours ago, Oli1549 said:

Yeah the IP that it was given by the router has obviously changed because i cant connect to it.

If you go inside the router it should tell you what it changed to. Once you're back in give it a static IP then remove that address from the DHCP pool.

 

9 hours ago, Oli1549 said:

Ok, so, if i literally use a old router, connect that to the switch directly, allow it to do the DHCP and all the fancy stuff, then have the new router connected to the old router, providing internet? so if the internet one goes the only thing lost is an internet connection??

 

Maybe this will work somehow?

No, that wouldn't work. If one fails the whole network goes down. In enterprise environments there would be a managed switch or other managed device that would have 2 ports configured in fail-over or link aggregation. These ports would go off to two separate modems often from different providers so at any time if one disconnects the other immediately takes over. The other port(s) on the switch/like device would go off the rest of the local network.

 

This is often seen with modems setup in bridged mode and a router that supports 2+ WAN interfaces.