Thanks Juergen for the link, that was helpful. I found the but about ‘renewing’ … this says …
To renew certificates:
When your certificate is about to expire, it can be renewed using this option.
- Click CSR .
- Select Renew certificate and click Next .
- Download the generated private key and certificate signing request.
- Send the CSR to the desired certificate authority for a renewed certificate.
I have 2 certificates one from Letsencrypt and one from synology. I select the lets encrypt one then click CSR and have only 2 options:
Create a CSR and SIgn CSR - there isn’t a renew option. HOWEVER …
On the ‘Add’ dropdown tab along the top there is an option to renew - so I’ve tried that and recieved an error about port 80 needing to be open to letsencrypt so I think that’s my next area to investigate (I have changed my router since the original install so I guess I’ve some work to do)