First, download the new firmware from the official website of D-Link
http://forum.dlink.ru/viewtopic.php?f=2&t=92700
https://ftp.dlink.ru/pub/Switch/DES-3028/Firmware/
Archive with firmware will be unpacked on tftp server.
How to start a tftp server can be read in these articles:
Starting a TFTP server in Windows
Installing and Configuring a TFTP Server in Ubuntu
We connect to the switch via telnet and see what firmware is on it and which one is active:
show firm info
Unnecessary can be removed with the command:
config firmware image_id 2 delete
And load into its place a new (where 192.168.1.5 address of the tftp server):
download firmware_fromTFTP 192.168.1.5 DES_3028_52_V2.94-B22.had image_id 2
If the download does not work, then the firmware file on the TFTP server can be renamed to eg 2.had and run again:
download firmware_fromTFTP 192.168.1.5 2.had image_id 2
If it does not work, then the problem is more likely with a tftp server or a firewall that can block access.
To check the availability of ip, you can ping directly from the switch:
ping 192.168.1.5
When the firmware is loaded into the switch it must be done by running the command:
config firmware image_id 2 boot_up
Then save the configuration:
save
And we will reboot the router so that it boots with the new firmware:
reboot
Done.
By the way, you can also upload the configuration or logs of the switch to the tftp server:
upload cfg_toTFTP/log_toTFTP 192.168.1.5 file.txt
download cfg_fromTFTP/log_fromTFTP 192.168.1.5 file.txt