Wrong address range on cat5 connection

Fresh clean install (3rd time)
I'm at the end of the quick start guide. OpenWrt is set as Client Device (DHCP comes from ISP modem/router).
I have the following connections:
Cat5 cable from pc to OpenWrt lan#3
From OpenWrt wan to ISP modem/router's lan port#4
No internet available from Wireles or wired connection.
Wired nic IP received by DHCP:
Wireless nic

The wired nic receive when connected to ISP Modem (internet ok).
ISP modem/router is set to provide DHCP with a pool between and

I need fast cat5 connection as I plan to get a NAS running from OpenWrt.

What is preventing a connection to the internet when I connect to OpenWrt (TP-Link Archer C2600)?

169.254 addresses mean that Windows was unable to obtain a DHCP address.

The default configuration does almost what you want. The only problem is the default LAN IP is, which overlaps the ISP modem. So you must change OpenWrt to something else, like

In other words:

  • Start with default OpenWrt. Do not connect the router to the main network yet.
  • Connect your PC with a cable to one of the OpenWrt LAN ports and get a DHCP address of 192.168.1.X. Log into the router.
  • Change the OpenWrt LAN IP to
  • Reset the network on your PC so it gets a 192.168.2.X address from the OpenWrt router and log in again at
  • Now plug the WAN port of the router into your ISP modem. The default configuration is to obtain a WAN IP as a DHCP client, which is what you want.
  • The main status page should show a IPv4 WAN IP of 192.168.1.X and the Internet should work.

Could not connect to luci after changing the IP to
I kept guetting 169.254.x.x
Static IP set on ethernet card for correct range with no result.
Wireless connection was no better, rebooting router and pc with nothing else connected.

Checked sourcefile (Firmware OpenWrt Install) I got from (http://LINK) and compared the checksum : was way different. Download the file again = same wrong checksum.
Download tplink_c2600-squashfs-factory.bin
from LINK

I now have 3 files with the same checksum
5d b6 16 9e a8 60 b6 4c ac 34 60 07 b0 dd 48 13
and it is suppose to be:

Is there something wrong with the dowload or it's the wrong info on the site?

I reloaded the firmware from the vendor and everything is fine, Solid IP address.

Note: It was extremely hard to know what to do in what order from the information on the web site. Everything is listed alphabatically, not in the order it should be done. I have spend well over 20 hours. This was my second attempt with Linux in the last 15 years with similar pattern.

Not sure I can invest more time.
Pls relay this comment toward feedback on documentation that I came across at one point

Bottom line: I have a lot of experience supporting Win OS on large networks but with Linux I no experience. The documentation could not cover the gap.

There are different checksum or hash methods. If the number of bytes in the checksum is different, you're clearly using a different method than the other guy did. I think sha256 is the preferred method now.

The new LuCI "fallback" system means you only have 30 seconds to successfully log in again after changing the LAN IP, or it will revert on you. I really don't like that, though I seldom use LuCI any more.

Changing the LAN IP for good is very easy with SSH-- once you are using SSH.

Under LuCI I would do a process using a larger netmask so you don't have to re-configure the PC during the 30 second window. If you use a netmask of on the PC and the router, they own the entire 192.168.X.X range.

So it could go like this:

PC IP static (netmask
Router IP (default)

Change router IP to
Promptly type into address bar and log in again (LuCI now happy)

Change PC IP to
Log in and change router netmask to
Log in again

Change PC IP to DHCP
Confirm you have 192.168.2.X

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