Slow throughput from LAN to WAN

I have a 250mpbs internet connection, but It seems that I can't get above 150mbps from WIFI to WAN but I can WIFI to LAN.

I can get the full bandwidth of my ISP WIFI > LAN > router to ISP but WIFI > WAN > router to ISP only 150mbps.

To reproduce, connect via Wireless 5G and plug WAN port into lan side of internet router (I know it's multi natting this way but it shows the problem). In this configuration I cannot get more the 150mbps using If I move the WAN port from VLAN 2 to VLAN 1 so it's on the lan side in same configuration, speed test shows full throughput.

The OEM firmware works fine in this configuration and since the WIFI is ok in the "LAN" configuration, it seems that it's an issue in the VLAN setup itself. The oem firmware is a custom version Attitude Adjustment rc1 version of OpenWrt.

I would assume

  1. NAT
  2. Firewall
  3. Routing

Can you give me your /etc/config/network?

  • What device do you have?
  • Have you enabled Software NAT offloading on the Firewall page?
  • If your device is capable, have you enabled Hardware offloading on the Firewall page?

There's much more overhead in version 18.06.2 than in version 12 (Attitude Adjustment).

Hardware flow offloading hidden under software flow offloading did it! Many thanks lleachii!

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Why not turning wan into another switch interface? So turning AP into a dump AP...

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If your problem is solved, feel free to mark the relevant post as the solution; and edit the title to add "[SOLVED]" to the beginning (click the pencil behind the topic).


Why would the OP expose the AP to the ISP's network?

In most places, the ISP only issues one IP, attempting to obtain more IPs would be a Theft of Service in some jurisdictions.

I think I misunderstood the setup. He wrote something like router to isp and internet router. So there is still some box between ISP and WiFi-AP(?). And he wrote something like

(I know it's multi natting this way but it shows the problem)

I think with Wireless 5G he is not actually meaning 5 G. I think he is meaning the 5 GHz network? Why should you plug a 5G connection into your lan ISP internet router?


Cell WAN card!

They NAT anyway! I see your point!

The OP would be bypassing the OpenWrt DNS, but your idea will work's just that the OP would have to disable DHCP on one of the devices.

In Germany people would call you crazy if u would nat your home network via cellular network. :rofl:
Or you can afford to pay a huge amount to your cellular provider.
We will see how expensive base stations, expensive spectrum, mm-wave and small cells should change this situation. :stuck_out_tongue: (concept of 5G)

I think switching is more energy efficient? :slight_smile:

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I agree in theory, as the CPU wouldn't be doing any routing...but the aircard is doing more NATing.

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Lol. I was looking all over for the way to mark solved. Thx!

OK, ok! Man, I'm surprised at how active this post became. Nice to see things are active!

#1 - My config was only for testing. Not normal setup. I just put the Openwrt router in front of my router connected to the internet for testing between LAN and WAN while maintaining internet connectivity for speed tests.

#2 - 5g is 5ghz WiFi not 5g cellular network.

Thanks again for the help!

You tried to save few keystrokes in your first post and ended up spending a lot more explaining! :laughing:

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