If you experienced a blinking DIAG led on your Cisco router, you will have to reinstall a firmware using a dedicated procedure.
Download the latest firmware
You will find it on Cisco Support Website.
In my case, for a Cisco Small Business RV042G, the firmware can be found here.
Send it to your router using tftp
TFTP stands for Trival File Transfer Protocol. It's a FTP like protocole which allows a client to get from or put a file onto a remote host.
The file that will be uploaded will be automatically installed. To do that:
- open a Terminal
- go to the folder were you downloaded the latest firmware
Now type the following command
$ tftp 192.168.1.1 tftp> mode binary tftp> put RV0XX-v4.2.3.06-20150319-code.bin Sent 26284032 bytes in 11.5 seconds
Don't forget to send a
mode binary before you
put the file to the router. Otherwise, it won't install correctly.
A few seconds later, the router will reboot and will be accessible with its default URL.