Help: My N56U LAN ports stopped working

[asusguy]

Hi all,

I am in desperate need of some help. After 6-7 years of using my RT-N56U, my LAN ports suddenly died - all of them. They are still blinking orange, but seems like no Internet. Strangely, before I reset the router, I was able to communicate through the local LAN and still stream files from my NAS to the TV. WiFi still works flawlessly - both 2.4G and 5G. I tried many things:

- different cables
- different laptops with different Windows versions
- flashed latest Padovan firmware
- flashed latest stock firmware again
- unplugging for a couple of minutes my cable modem and the router

...and nothing works. I still only have WiFi. Can someone tell me if the LAN ports are dead and the only solution is to buy a new router?

IPCONFIG / ALL on a Windows 10 PC
=================================

Ethernet adapter
Connection-specific DNS Suffix . :
Description . . . . . . . . . . . : Intel(R) Ethernet Connection I218-LM
Physical Address. . . . . . . . . : 34-xx
DHCP Enabled. . . . . . . . . . . : Yes
Autoconfiguration Enabled . . . . : Yes
Link-local IPv6 Address . . . . . : fe80::xxxx(Preferred)
Autoconfiguration IPv4 Address. . : 169.xxx.xxx.xxx(Preferred)
Subnet Mask . . . . . . . . . . . : 255.255.0.0
Default Gateway . . . . . . . . . :
DHCPv6 IAID . . . . . . . . . . . : 705xxxx
DHCPv6 Client DUID. . . . . . . . : 00-01-00-xx..
DNS Servers . . . . . . . . . . . : 217.x.xxx.xx
217.x.xxx.xx
NetBIOS over Tcpip. . . . . . . . : Enabled


==================================
Wireless LAN adapter Wi-Fi: -- works OK
Connection-specific DNS Suffix . :
Description . . . . . . . . . . . : Intel(R) Dual Band Wireless-N 7260
Physical Address. . . . . . . . . : 80-xx
DHCP Enabled. . . . . . . . . . . : Yes
Autoconfiguration Enabled . . . . : Yes
Link-local IPv6 Address . . . . . : fe80::xxxx
IPv4 Address. . . . . . . . . . . : 192.168.xxx.xxx(Preferred)
Subnet Mask . . . . . . . . . . . : 255.255.255.0
Lease Obtained. . . . . . . . . . : Friday, June 14, 2019 4:12:23 PM
Lease Expires . . . . . . . . . . : Saturday, June 15, 2019 4:12:22 PM
Default Gateway . . . . . . . . . : 192.168.xxx.xxx
DHCP Server . . . . . . . . . . . : 192.168.xxx.xxx
DHCPv6 IAID . . . . . . . . . . . : 75503924
DHCPv6 Client DUID. . . . . . . . : 00-XX
DNS Servers . . . . . . . . . . . : 192.168.xxx.xxx
NetBIOS over Tcpip. . . . . . . . : Enabled


And here is the info from my Windows 7 PC
==========================================
Ethernet adapter Local Area Connection:
Connection-specific DNS Suffix . :
Description . . . . . . . . . . . : Atheros AR8151 PCI-E Gigabit Ethernet Controller
Physical Address. . . . . . . . . : 60-xx
DHCP Enabled. . . . . . . . . . . : Yes
Autoconfiguration Enabled . . . . : Yes
Link-local IPv6 Address . . . . . : fe80::xxxx
Autoconfiguration IPv4 Address. . : 169.xxx.x.xx(Preferred)
Subnet Mask . . . . . . . . . . . : 255.255.0.0
Default Gateway . . . . . . . . . :
DHCPv6 IAID . . . . . . . . . . . : 25800xxxx
DHCPv6 Client DUID. . . . . . . . : 00-xx
DNS Servers . . . . . . . . . . . : fec0:0:0:ffff::1%1
fec0:0:0:ffff::2%1
fec0:0:0:ffff::3%1
NetBIOS over Tcpip. . . . . . . . : Enabled

 

[L&LD]

Your ports may very well be hardware issues, but until you do a full reset to factory defaults after flashing the firmware you want to use on the router and then minimally and manually configuring it (do not use a saved backup config file) to secure the router and connect to your ISP, you won't know for sure.

See my signature below for the M&M Config to get your router and the rest of your network to a good/known state once more.

 

[asusguy]

See my signature below for the M&M Config to get your router and the rest of your network to a good/known state once more.

Thank you for the guidance. I don't see sig on mobile, but once I get to my PC will check it out. For now I left the cable modem and router unplugged to stay like that a few hours.

 

[L&LD]

Thank you for the guidance. I don't see sig on mobile, but once I get to my PC will check it out. For now I left the cable modem and router unplugged to stay like that a few hours.

You're welcome.

On mobile, try turning your phone and browsing the forums in landscape mode and the signatures should be visible.

 

[asusguy]

See my signature below for the M&M Config to get your router and the rest of your network to a good/known state once more.

Hi L&LD,

I am trying to follow your instructions for M&M Config. However, for the N56U many of them are not there... such as:

• Disable NFSD.
• Spanning Tree Protocol: Disabled.
• Format JFFS partition at next boot: Yes.

Now, if needed, Enable JFFS custom scripts and configs. Reboot and wait 5 minutes after the router comes up.

None of the above options are there to be manipulated. Ans not sure how important is the JFFS partition formatting but I do not see anything related in the GUI. My guess is N56U is pretty old and some of those functions are just not there.