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Akey_scott's profile

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Tue, Mar 1, 2022 3:20 PM

Can cell booster run off repeater router?

I am trying to install a SS1FII cell booster, but ned to connect it to a secondary router which is hardwired to the house's primary service router. It does not seem to activate. Do I have to connect to the first (primary) router?

Community Support


192K Messages

4 m ago

Great question, @Akey_scott! There are useful tips that can help resolve your Broadband/Transport connectivity experience related to the AT&T Cell Booster.


As recommended at Find and fix AT&T Cell Booster issues, you will want to make sure that your Ethernet cable is connected to the WAN port on your Cell Booster and your router or gateway.


Even if you have a modem and a separate router, try connecting your Cell Booster directly to your modem.


Also, if your internet LED flashes orange or white, it’s having an internet connectivity issue. There are other troubleshooting tips, including:

  • Check the internet connection on other devices.
  • Restart your router or gateway and your Cell Booster device.

If none of these fix that trend with your Cell Booster, get advanced help for firewall and routers. As advised, installing the AT&T Cell Booster behind a firewall, or behind a router with firewall capabilities, requires the following ports be opened to prevent the firewall from blocking communication with the network.


Note: Customers attempting to connect a AT&T Cell Booster on their corporate Internet connection may experience connection issues. The AT&T Cell Booster is designed to function using a direct Internet connection.


Local transport requirements

Confirm the following router/switch settings prior to activating your AT&T Cell Booster:

1. DHCP is ON.

Note: For installations where static assignment of an IP address is desired the use of MAC Binding and static DHCP Reservation is suggested. Static IP is not supported.


2. MTU size is set to 1500 or higher.

3. MAC address filtering is either turned off or allows the MAC address of the Cell Booster.

4. IPSec Pass-Through is Enabled.

5. Block Fragmented Packets is Disabled.


Give this a try and let us know how this works for you. Thank you for contacting AT&T Community Forums.


Lar, AT&T Community Specialist


ACE - Expert


18.1K Messages

4 m ago

@Akey_scott Your setup sounds like a double NAT issue. In your case, the Cell Booster would need to be directly connected to the primary router or the router providing DHCP. See my Tech Guide, link is in my sig line, for proper setup and installation of the Cell Booster.

I'm going to move this post to the Cell Booster forum.




118 Messages

4 m ago

Agreed w/ @OttoPylot

You may have a "double NAT" situation going on that can heavily confuse things. 

On your secondary, hardwired router: 

Turn OFF all DHCP services. If available, turn ON DHCP pass-through and IPSEC pass through. If available, allow packet fragmentation. Make your secondary router as dumb as possible and shut down any and as much firewall functions as possible. Essentially you're making a glorified switch with a Wi-Fi AP built on the back of it.

(Assuming you're set up this way to make a mesh/grid environment to get stonking-strong Wi-Fi in a large home)

On primary router/AP:

Lock a "sticky" DHCP assigned address to your Cell Booster's MAC. Verify that the booster remains on lock after main router reboot. Drop the Booster's sticky IP address into primary router's DMZ.





ACE - Expert


18.1K Messages

4 m ago

@Akey_scott Do you still need help and have you read thru my Tech Guide?

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