Networking help again

[boybi]

This is my setup at my home and office:

DSL Modem---Wifi Router 1---[LAN cable]---Wifi Router 2---<wirelessly bridged to>---Wifi Router 3---[LAN cables]---Office computers & server

Blue = Home
Red = Office

Routers 2 & 3 serve as access points/hubs
Router 1 assigns the IP addresses.

Here's my problem:

There are times the power cord for the Router 2 gets unplugged accidentally, so the office side will lose internet connection. If the computers in the office are turned on before the Router 2 is unplugged, they can still access the server since they've already been assigned their respective IP addresses.

But if Router 2 was unplugged before the office computers were turned on, then none of the office computers get to access the server.

What I like to know is, can the office side have it's own DHCP separate from the home side? I mean, I want the office and home to have their own separate networks, but the office side still get its internet connection from my home network. Is this possible?

If I can do this, can the office computers still have access to files stored on my home computers?

[ghosthunter]

Do you have DHCP service turned on with router 3?

Also,

Can you simply connect Router 3 to Router 1? This would help speed up your LAN.

[boybi]

DHCP is turned off in routers 2 & 3.

Router 1 is beside my computer. I need router 2 to be able to reach router 3.

[ghosthunter]

DHCP is turned off in routers 2 & 3.

Router 1 is beside my computer. I need router 2 to be able to reach router 3.

You can turn on the DHCP on router 3 but assign it a different IP group/range.

Example:
Router1 group: 192.168.1.X
Router2 group: 192.168.2.X
Router3 group: 192.168.3.X

Also on router 3, simply assign the IP address of router 1 as it's gateway.

This would let any PCs connecting to router 3 to get a "local" IP (from router 3) yet still get internet from router 1.

[oj88]

You can turn on the DHCP on router 3 but assign it a different IP group/range.

Example:
Router1 group: 192.168.1.X
Router2 group: 192.168.2.X
Router3 group: 192.168.3.X

Also on router 3, simply assign the IP address of router 1 as it's gateway.

This would let any PCs connecting to router 3 to get a "local" IP (from router 3) yet still get internet from router 1.

Just a note. If you're using a 24-bit mask (255.255.255.0) which is usually the default subnet mask on most router's LAN configuration, that won't work. You need to use a 22-bit masks or lower.

[boybi]

Just a note. If you're using a 24-bit mask (255.255.255.0) which is usually the default subnet mask on most router's LAN configuration, that won't work. You need to use a 22-bit masks or lower.

How to do the 22-bit mask?

[oj88]

You can:

1. Secure the plugs on all routers with zip ties or duct tape, or
2. On the office Windows clients, you can statically assign the IP address, subnet mask, gateway and DNS entries in the Alternate configuration tab.

You most likely wouldn't want to turn on the DHCP server on Router 3, since the gateway IP address it will advertise is itself, and not Router 1. But in the off-chance that you can define the gateway on the DHCP server on Router 3, then this would be the best solution next to #1 above. So, for Router 1, you can set the range of IP addresses it can issue via DHCP from say, 192.168.x.51 - 100 and on Router 3; 192.168.x.101 - 150, depending on how many computers you have on either buildings. The two DHCP servers (Routers 1 and 3) should not overlap or you'll have duplicate IP issues.