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haccks
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What Private Network IP Address should I asighn to the Internal LAN?

Mon Apr 11, 2016 6:46 pm

My RB450G is connected to a Cisco router on ether5 (WAN). ether1 is used for LAN and my computer is connect with this port via Ethernet cable. Setup is shown in the diagram below:

Image

I added two addresses in address list, one for WAN with IP 192.168.1.114/24 and another for LAN with IP 192.168.0.1/24. After configuring the setup it shows there is No Internet.
How can I fix this? What IP address Should I assign to the LAN?
 
pe1chl
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Re: What Private Network IP Address should I asighn to the Internal LAN?

Mon Apr 11, 2016 7:14 pm

What is your reason for not using a default setup, i.e. port 1 connected towards internet and using the default
LAN address range of 192.168.88.1/24 ?
 
haccks
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Re: What Private Network IP Address should I asighn to the Internal LAN?

Mon Apr 11, 2016 7:37 pm

What is your reason for not using a default setup, i.e. port 1 connected towards internet and using the default
LAN address range of 192.168.88.1/24 ?


Purpose is to learn how to customize it.
 
Sob
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Re: What Private Network IP Address should I asighn to the Internal LAN?

Mon Apr 11, 2016 8:20 pm

The most likely problem with this setup is missing route to 192.168.0.1/24 on Cisco router. You must tell it that it's behing 192.168.1.114, otherwise it has no idea where to find it and will try to reach it using default route, i.e. send packets to ISP and that's not where your 192.168.0.1/24 is.

If you can't change Cisco's config, you have to use NAT, the same way as if your RB was connected directly to ISP.
 
haccks
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Re: What Private Network IP Address should I asighn to the Internal LAN?

Mon Apr 11, 2016 9:09 pm

The most likely problem with this setup is missing route to 192.168.0.1/24 on Cisco router. You must tell it that it's behing 192.168.1.114, otherwise it has no idea where to find it and will try to reach it using default route, i.e. send packets to ISP and that's not where your 192.168.0.1/24 is.

If you can't change Cisco's config, you have to use NAT, the same way as if your RB was connected directly to ISP.

OK. If I connect directly to ISP then should it work?
 
Sob
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Re: What Private Network IP Address should I asighn to the Internal LAN?

Mon Apr 11, 2016 11:02 pm

If you connect RB directly to ISP instead of Cisco, then of course it won't work without some config changes. Did you perhaps miss what I was trying to tell you?

Once again, with the original setup you have two options (if you want to have separate subnet):

a) On Cisco, add static route to 192.168.0.0/24 with gateway 192.168.1.114. If you do this, internet access from 192.168.0.0/24 will work. Also most likely computers from 192.168.0.0/24 and 192.168.1.0/24 will be able to communicate with each other (but it also depends on Cisco).

b) On RB, enable NAT on WAN port. This way, all connections from 192.168.0.0/24 will be hidden behind common address 192.168.1.114 and no configuration will be necessary elsewhere. But you'll have double NAT, which is not the best thing.
 
haccks
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Re: What Private Network IP Address should I asighn to the Internal LAN?

Thu Apr 14, 2016 5:12 pm

If you connect RB directly to ISP instead of Cisco, then of course it won't work without some config changes. Did you perhaps miss what I was trying to tell you?

Once again, with the original setup you have two options (if you want to have separate subnet):

a) On Cisco, add static route to 192.168.0.0/24 with gateway 192.168.1.114. If you do this, internet access from 192.168.0.0/24 will work. Also most likely computers from 192.168.0.0/24 and 192.168.1.0/24 will be able to communicate with each other (but it also depends on Cisco).

b) On RB, enable NAT on WAN port. This way, all connections from 192.168.0.0/24 will be hidden behind common address 192.168.1.114 and no configuration will be necessary elsewhere. But you'll have double NAT, which is not the best thing.

Thanks. That worked.