I have an Asus RT-N56U flashed to the latest 18.06.4, and it was working fine. I added a buggy script to Startup, which included a "reboot" command that always trigger. Now, my router is in a reboot loop.
I thought the best way to recover is to enter failsafe. I pressed the reset button repeatedly on power up, and it got into failsafe mode because the LED blinks rapidly non-stop.
I disabled WiFi on my Macbook, configured its LAN interface to 192.168.1.100/24, plugged a LAN cable to LAN port #1 on my N56U, and then SSHed to the router at 192.168.1.1, but I get the error "host is down". Same error message for ping.
I did an ARP but found no MAC address at 192.168.1.1. The LAN port on the router lights up indicating the Ethernet port works.
What am I doing wrong?
Update: I fixed the problem. Please refer to my reply below.