On the test, I will update the firmware of the D-Link DES-3828 switch with version 4.50.B23 to 4.61.B35 (firmware without WEB).
First we make a backup copy of the configuration to the TFTP server:
upload cfg_toTFTP 192.168.1.1 3828.cfg
How to start the TFTP server I described in these articles:
Starting a TFTP server in Windows
Installing and Configuring a TFTP Server in Ubuntu
Let’s see which firmware version is installed and under which ID:
show firmware information
I have installed under ID 1, for this new one I will upload under ID 2:
download firmware_fromTFTP 192.168.1.1 DES3828R46_4.61.B35.had image_id 2
We make the firmware under ID 2 boot:
config firmware image_id 2 boot_up
After executing the above command, the switch will offer to perform a reboot, which we will agree to by pressing “y”. Done, the switch will start with the new firmware, the settings will remain unchanged.
P.S. I tried to make the boot firmware back under ID 1, after which the configuration remained, but the switch IP was reset to the standard 10.90.90.90. I had to connect to it via the console and set the previous IP, then you can also download a previously made copy of the configuration to the switch with the command:
download cfg_fromTFTP 192.168.1.1 3828.cfg