I have network setup in my home with 3 different wireless routers. I have only the main router DHCP server running since my printserver only allow connections from its IP range.
The setup is like this:
Modem / wifi router on 1st floor, in front room - i'll call it MASTER.
2nd wifi router on Ground floor, right beneath 1st router - let's call it OFFICE and it's only have 1 LAN port.
3nd router on 1st floor, on back room - let's call it ACC. It has 4 LAN ports.
From MASTER i have a RJ45 cable running down to OFFICE, and here I have a 8-port hub, which run RJ45 cables to all other rooms, to the other routers. The print server in OFFICE also connect to this hub.
The DHCP server in OFFICE is disabled since the printserver only allow connection from devices in the same IP range.
Now i want to make it into one Network coz I have to manually switch to stronger signal network on my devices (phone / laptop / ipad), since they tend to stick to the old one, even thou it's only 1 bar of signal strength.
I tried changing OFFICE router into a repeater by changing its SSID and password the same as MASTER. But its always say 'Limited', and I could not connect to OFFICE anymore unless I manually input IP address and gateway...
You can have the same SSID in use, just ensure they use different channels, you need to configure the PC's NIC cards roaming setting for it to latch on to strongest signal.
On the subject of IP address, the slave routers should be connected back the master router by its LAN ports and not the WAN port. Also, no IP details should be entered for WAN connection, put a static IP in the LAN connection section.
How to set up the NIC? I went to Computer > Manage and my NIC is Atheros Qualcomm, couldn't find any tweak regarding roaming...
On IP address, my MASTER lan is 192.168.1.1, my OFFICE is *.2.1 and my ACC is *.0.1 - should i input a static IP into my Wireless Network setting like IP: 192.168.1.99 and Gateway 192.168.1.1 ? It would be inconvenient if i go out to some other place..
It should have a option under the advanced tab in the same general area you would replace the device driver. It is not under the part of the screen with the tcpip setting and stuff it is in the hardware setting for the nic itself.
Unless there is some feature you need on your other routers that does not work when you run them as AP you want to only have a single main router and run the other devices as AP. You want the main router to control all the IP addresses and any routing to the internet.
Roaming is a massive issue and vendors even have complete product lines to address this. Cisco in general calls this ipmobility since they allow you to roam back and forth between WiFi networks and cellular broadband.
In your case you have 3 issues.
First is the simple ability to get the device to switch back and forth. Without a special client loaded to control this like switching based on number of users connect to the AP or based on utilization you are stuck with the simple when the signal level drops to a defined level go look for a stronger device. This tends to be tricky since if you set it to low it will spend all its time jumping back and forth.
Next you have the issue of the IP blocks. If you were to use the same SSID but allow your router to run as router and give out different subnet based on the device you connect to. Now when the roaming thing switches the PC must detect this switch and ask the DHCP router for a different IP since the one it has won't work. Most times it is too stupid to detect this and will just keep trying to use the wrong IP. But now lets assume you do manage to get a different IP address. Everything you had open will now have to be redone. Since your IP changes every machine you are communicating with will now assume you are some different and you will have to relog into or whatever. There is no solution for this in a home environment. The commercial installation solve this with a form of VPN so only you can keep a fixed virtual address. This is the key reason you want to run you devices as AP and not routers to avoid this issue.
And last since I will assume you are using encryption you will have to reauthenticate and regenerate keys every time you switch AP. This will cause a small stall and if you are using some of the enterprise level options you will have to key in a userid and password. In most cases using a pre shared key and WPA2 you should just see a few seconds of hang when it does this. Again you need to make sure you do not flap back and forth this delay will cause you massive issues.