Importing external TLS certificates

You must import an external TLS certificate on any host that sends encrypted email.

Procedure

Copy the TLS certificate to the /etc/pki/ca-trust/source/anchors/ directory on the host that sends encrypted email.
For example, to import a certificate titled TLS_email.crt, type the following command:
```
openssl s_client -connect <emailServer>:<port> < /dev/null | openssl x509 /etc/pki/ca-trust/source/anchors/TLS_email.crt
```
To update the certificates in the certificate authority (CA), type the following commands:
```
update-ca-trust enable
```
```
update-ca-trust extract
```