1. Company using Ubuntu Linux server with multiple true IPs broadband line, I am finding some email server + webmail applications solution for Ubuntu Linux, email server can handle multiple email domain, as using Linux, freeware email server will be considered, some website suggested Postfix + Dovecot + Openwebmail, is it good for setup or any other email solution you suggest to!
2. Based on Q1, should I enable DNS Bind on Ubuntu if running email system on Ubuntu Linux.
3. Normally, MX records has two, but company only have one Linux server, if enable email system, only one MX record is that OK!