SED delete lines between two pattern matches

Question

I am trying to replace lines between two pattern/string matches using SED see below. I need to delete lines below interface GigabitEthernet0/3 up to inter

Answer 1

This might work for you:

sed -e '\#^interface GigabitEthernet0/3#,/^!/{//!d}' input_file

or as you described it in the question:

sed -e '\#^interface GigabitEthernet0/3#,\#^interface GigabitEthernet0/4#{//!d;/4/s/^/!\n/}' input_file

presuming you want to preserve the ! on the line prior to the second interface. If you don't want the ! then omit /4/s/^/!\n/ from the last bit of the sed command