I solved it little differently by logging into the OPNSense console with following steps:
1. grep -n openvpn-server /conf/config.xml | sed 's/:/ /' --> this will give you the line number where OpenVPN server specific line numbers
2. cat -n /conf/config.xml | sed -n '6478,6500p' --> replace line numbers with your machine specific details, this will show you the entire block
3. nano +6478 /conf/config.xml -> this will open nano at the specified line number
4. CTRL+K --> deletes the line at cursor position, delete the entire block between <openvpn-server> </openvpn-server>
5. Exit from shell and reload all services from command line, you should be able to see from GUI that the openvpn-server instance that you wanted to delete is no longer there.
And before you do any of the above, backup your config.xml file!
1. grep -n openvpn-server /conf/config.xml | sed 's/:/ /' --> this will give you the line number where OpenVPN server specific line numbers
2. cat -n /conf/config.xml | sed -n '6478,6500p' --> replace line numbers with your machine specific details, this will show you the entire block
3. nano +6478 /conf/config.xml -> this will open nano at the specified line number
4. CTRL+K --> deletes the line at cursor position, delete the entire block between <openvpn-server> </openvpn-server>
5. Exit from shell and reload all services from command line, you should be able to see from GUI that the openvpn-server instance that you wanted to delete is no longer there.
And before you do any of the above, backup your config.xml file!
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