How to configure 2 subnets on same LAN talk to each other

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TheR0cket

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#275922 17-Sep-2020 03:30

Hello All,

I need your help and advice with my home network please. Thank you for viewing this post and your help in advance.

Scenario

I changed my ISP to SPARK and received a brand new SPARK Smart Modem

The previous IPS modem was the useless NetComm NF18ACV which total control belong to the ISP customer service which has very weak signal on both 5G & 2.4G so I bought the Asus AiMesh RT-AC68U 2 Pack hoping it would improve speed and coverage.

Like the previous ISP, I connect the RT-AC68U to SPARK Mode and found:

SPARK Smart Modem

LAN IP Addrs / Gateway: 192.168.1.254

IP Addrs Pool: 192.168.1.64 ~ 253

Asus RT-AC68U - Setup under Wireless Router mode / Aimesh Router mode (default)

WAN IP 192.168.1.65

LAN IP Addrs / Gateway: 192.168.2.1

IP Addrs Pool: 192.168.2.2 ~ 254

Devices connected to ASUS are my NAS, Media Player and home computers.

Problems:

If I connected to the internet via the Asus router, I can access all mentioned above fine but if I connect via SPARK, I can't access the Asus network.

Would you be able to give me instruction (for dummies) to configure the two subnets to communicate please.

Please ask if you need more infos in order to find a solution.

Thanks a lot

Jase2985

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#2566387 17-Sep-2020 06:55

turn off the DHCP server on one of the devices so only one is giving out the IP address range you want. you shouldn't need 2 subnets for a simple home network.

which device is acting as the router and connecting to the internet?

personally i would keep the spark smart modem, and if you need more wifi coverage buy one of their smart mesh units. then sell the asus router.

nztim

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#2566388 17-Sep-2020 06:59

Hi There

I don't know if the NF18AV is the same as the NF4V but if it is - the default configuration, with the factory firmware will be an access point with a 5 port switch

1. Download generic firmware from here https://support.netcommwireless.com/products/NF18ACV

2. flash the modem with the generic firmware

3. factory reset the modem, the default IP will be 192.168.20.1 username/password will be admin/admin

4. Once factory reset all ports will be bridged to be a 5 port switch, change the netcomm IP address to 192.168.1.253, disable DHCP server, and setup your desired wifi SSID and key

Any views expressed on these forums are my own and don't necessarily reflect those of my employer.

TheR0cket

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#2566637 17-Sep-2020 09:44

Jase2985:

turn off the DHCP server on one of the devices so only one is giving out the IP address range you want. you shouldn't need 2 subnets for a simple home network.

which device is acting as the router and connecting to the internet?

personally i would keep the spark smart modem, and if you need more wifi coverage buy one of their smart mesh units. then sell the asus router.

Thank you Jase2985 for your time and valuable input.

The Spark Smart modem is the router and connecting to the internet. The Asus is cover my home network which control access to my NAS, my kids' computers, streaming media to TV etc.

I'll try to do as per your instruction, will let you know the result when I done so.

Hi NZTim,

Thank you for your input.

But I returned it back to the ISP when I moved back to SPARK - I hate that modem anyway. 😬

Jase2985

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#2566663 17-Sep-2020 10:02

if thats the case then turn the DHCP server off on the Asus, and change the DHCP server on the spark router to be the same subnet range as what the asus had 192.168.2.2 ~ 254. this should keep the NAS etc happy.

TheR0cket

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#2578691 3-Oct-2020 18:12

Hi Jase2985,

Sorry for being so quiet since out last post. Have been so busy (all of a sudden) since we moved down to Level 1😃 👍 and has not found time to fiddle with my home network until now.

The RT-AC68U has 4 different mode (See screenshot) and the best and default mode is AiMesh, I didn't really want to config it to AP mode (2nd option) because of this AiMesh vs. Repeater vs. Access Point (https://www.youtube.com/watch?v=ic0bgo_ueQ0) I found from YouTube, as the test he did say AP mode will be slower (and Repeater would be worse) compare to the default AiMesh mode.

But since your advice, I tried config the router to AP Mode / AiMesh Router in AP Mode and man, it was a straightforward easy as process. And everything just fall into its place.

I created the static reservation in Spark Smart Modem (Network > Routing > Static Route) for the Asus Router.

Now my network only have one subnet 192.168.1.64 ~ 253, the subnet 192.168.2.2 ~ 254 GONE!

This topic now can be closed/Resolved.

Jase2985

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#2578694 3-Oct-2020 18:31

Thats ok, glad you got it sorted.