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XueHai8
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Joined: Mon Jul 24, 2017 12:19 pm

Can''t access Pi from other Subnet

Sun May 06, 2018 9:22 am

I have multiple subnets on my home network and 3 of my Pi's are on 192.168.3.x
If my PC is on 192.168.2.x, then I can't connect via SSH to any of the Pi's on 192.168.3.x
Is this a setting in the Raspberry Pi or would be something in my Router?
Thanks!

epoch1970
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Joined: Thu May 05, 2016 9:33 am
Location: Paris, France

Re: Can''t access Pi from other Subnet

Sun May 06, 2018 9:33 am

To go from network to network, packets have to pass through a gateway (aka router).
The router has one leg on each network and can filter and forward as required.

The device you want to configure is the one that accesses/manages both networks, probably your ISP router.
"S'il n'y a pas de solution, c'est qu'il n'y a pas de problème." Les Shadoks, J. Rouxel

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XueHai8
Posts: 42
Joined: Mon Jul 24, 2017 12:19 pm

Re: Can''t access Pi from other Subnet

Sun May 06, 2018 12:29 pm

Ok. I think I understand now. Thought it might be something with the Pi that was keeping me out from another subnet.
I'll dig around my router's rules and learn up on it.
Thanks!!

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rpdom
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Location: Chelmsford, Essex, UK

Re: Can''t access Pi from other Subnet

Sun May 06, 2018 2:16 pm

There are two things that are required.

Firstly a router that will route traffic from one subnet to the other.

Secondly, every machine on those subnets will need to know the IP address of the router, so it knows how to get to the other subnet.

drgeoff
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Joined: Wed Jan 25, 2012 6:39 pm

Re: Can''t access Pi from other Subnet

Sun May 06, 2018 4:13 pm

rpdom wrote:
Sun May 06, 2018 2:16 pm
There are two things that are required.

Firstly a router that will route traffic from one subnet to the other.

Secondly, every machine on those subnets will need to know the IP address of the router, so it knows how to get to the other subnet.
Many ISP supplied routers do not support multiple subnets.

hippy
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Location: UK

Re: Can''t access Pi from other Subnet

Sun May 06, 2018 4:36 pm

XueHai8 wrote:
Sun May 06, 2018 12:29 pm
I'll dig around my router's rules and learn up on it.
You might need a switch rather than router to handle multiple subnets on the same network.

Some routers are effectively switch-plus-router, will put everything coming in from the LAN side out on all other cables on the LAN side, others won't.

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XueHai8
Posts: 42
Joined: Mon Jul 24, 2017 12:19 pm

Re: Can''t access Pi from other Subnet

Mon May 07, 2018 3:03 am

I have a pfSense router with 4 physical Lan Interfaces. So apparently I just gotta learn how to set up routing on it. :)
Thanks all!

epoch1970
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Location: Paris, France

Re: Can''t access Pi from other Subnet

Mon May 07, 2018 8:40 am

XueHai8 wrote:
Mon May 07, 2018 3:03 am
I have a pfSense router with 4 physical Lan Interfaces. So apparently I just gotta learn how to set up routing on it. :)
Thanks all!
I don't think you need to do much on the router, except to setup filtering to allow traffic to flow between the interfaces you're interested in.
"S'il n'y a pas de solution, c'est qu'il n'y a pas de problème." Les Shadoks, J. Rouxel

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