If you mainly want to “hide” your IP, you can’t. Look at the headers of any message. It’ll still show the original source IP, which will be yours.
For the rest of the time I’d recommend getting a spam filtering service. Mimecast, ProofPoint, Barracuda, etc.
Messages sent to you go to the filter, which then forwards the message over to your mail server. Outbound you configure your server to use the filter as a smart host. These filters will also buffer messages if your mail server is offline. So if the server is down, the filter holds on to messages and retries delivery later when your server is back up (within reason).
If you mainly want to “hide” your IP, you can’t. Look at the headers of any message. It’ll still show the original source IP, which will be yours.
For the rest of the time I’d recommend getting a spam filtering service. Mimecast, ProofPoint, Barracuda, etc.
Messages sent to you go to the filter, which then forwards the message over to your mail server. Outbound you configure your server to use the filter as a smart host. These filters will also buffer messages if your mail server is offline. So if the server is down, the filter holds on to messages and retries delivery later when your server is back up (within reason).