Encrypt a Tar Archive with OpenSSL

$ openssl des3 -salt -in unencrypted-data.tar \
-out encrypted-data.tar.des3
enter des-ede3-cbc encryption password:
Verifying - enter des-ede3-cbc encryption password: 

To unlock the encrypted file, use the following command:
$ openssl des3 -d -salt -in encrypted-data.tar.des3 \
-out unencrypted-data.tar
enter des-ede3-cbc encryption password: 

Postfix | Set postfix to read host file

 lmtp_host_lookup = native  
 smtp_host_lookup=native  
 #disable_dns_lookups = yes  
 ignore_mx_lookup_error = yes