How to use two different ISP on same LAN with one Ethernet switch?

Question

Sorry if same question is asked on Stackoverflow. I searched and tried some configuration but are not working in my case.

I have a LAN with 6 machines which are on same network (each other can be accessed using name and IP Address). I was using BSNL net connection till now. Now I have bought AIRTEL 4G connection. I dont want to disconnect BSNL conection. I want my 3 machines to use AIRTEL net connection and rest 3 to use BSNL connection only. At the same time I also want each machine to interact with each other in same previous manner.

How should I setup network for these? What configuration will I need for BSNL modem and Airtel Modem? What IP Address configuration will I need for each machines with subnet mask and gateway?

Thanks.

Solution

Connect the Airtel to the switch first. Then configure the Airtel with a free IP address on the same subnet as the other hosts and then change the default router on the three desired hosts which need to connect through the Airtel router.

If you use DHCP on the LAN, make sure you have DHCP configured (disabled) correctly before connecting the Airtel device to the switch.

If, for instance, the IP address of the BSNL is 192.168.1.1 and 192.168.1.2 is not in use, you can use that address on the LAN interface of the Airtel device. Use that address (192.168.1.2) as default gateway on the three hosts which need to connect through the Airtel device.

Comments

[Vishal Vaishya]

@Lenniey Can you please give more information on this. Like IP Address for Airtel modem and BSNL modem. And IP address and gateway address for machines to use Airtel connection.

[Lenniey]

look at Lamberts answer...I won't configure your network for you, some things you have to do yourself.

[Vishal Vaishya]

yes. trying with Lambert solution. and sorry for requesting detailed answer as am not Network Engineer so don't know much in depth.

[Vishal Vaishya]

@Lamert A quick and small question. Am not able to access Airtel router from browser but when I connect it directly I am able to with IP address 192.168.1.2

[Lambert]

@VishalVaishya, there are multiple scenarios and unfortunately it is impossible to discuss them all in comments. Besides, this it not the right way to troubleshoot such issues. In general it is best to provide as much info as you can collect such as IP configurations when directly connected and when connected to the switch and so on. Try to add such info to the question and I will try to answer it in another answer to this question.