Before upgrade save your settings. (your mnt could be different)
Restore only the settings from settings.txt that you are absolutely sure off.
For example:
Code examples are found somewhere here on the forums. It's not my creativity.
Code:
nvram show > /mnt/sda1/settings.txt
Restore only the settings from settings.txt that you are absolutely sure off.
For example:
Code:
nvram set dhcp_staticlist="values_previously_saved"
nvram commit
Code examples are found somewhere here on the forums. It's not my creativity.