Again, you’ll need the fullchain.pem file but with the appended DST Root CA X3 certificate that was prepared in this article.
Navigate to Templates and then under Security, click on the SSL/TLS tab.
First we need to import each of the CA certificates in the chain before we import the certificate for the Avi Controller.
Again the certificates in the fullchain.pem file in order are
Subscriber Certificate R3 Certificate ISRG Root X1 Certificate DST Root CA X3 Certificate
Click on CREATE, Root/Intermediate CA Certificate. Then import each certificate individually starting from the bottom. Click on Validate and then Import.
Do this again for the other two certificates, the ISRG Root X1 certificate and then the R3 intermediate certificate. Once done, you’ll see the following.
The Subscriber certificate is done differently.
Click on CREATE, Controller Certificate. Then give the certificate a name, click on the Import option and browse to the fullchain.pem file and also the privkey.pem file. A passphrase is not required as Let’s Encrypt does not create a passphrase. Click on Validate and then Import.
Once done, you’ll see the following.
Now that we’ve imported the Let’s Encrypt CA certificates, we can proceed to change the SSL certificate used by the Avi Controller for HTTPS web management.
Navigate to Administration, Settings, Access Settings, then click on the pencil icon.
Delete all of the current certificates in the SSL/TLS Certificate box and then select the new Subscriber certificate that we imported earlier, in my case I named it star-vmwire-com.
Once you press Save, you can close the browser session and open up a new one to start enjoying secure connections to your Avi Controller.