Setting up internal Bind DNS for Zimbra mail server on Amazon EC2 CentOS & RHEL Servers

Zimbra Collaboration server needs to resolve MX records of a domain while installing. Amazon EC2 instances are behind NAT so we need to have an working internal DNS server to do the MX resolution.

1. Install Bind

yum install bind9 -y

2. Add required changes on bind configuration file. Need to change forwarder and add zone for the domain.

vi /etc/named.conf

Find and replace the forwarders with the below (it is a google DNS servers we are using)

forwarders { 8.8.8.8; };

Add zone information in named.conf (replace mail.example.com with your domain) Continue reading Setting up internal Bind DNS for Zimbra mail server on Amazon EC2 CentOS & RHEL Servers

Zimbra & Sendgrid SMTP Setup

All the operations need to be done as a Zimbra user.

1. Point a domain to an SMTP server

zmprov ms mail.example.com zimbraMtaRelayHost smtp.sendgrid.net


2. Add SMTP authentication for smtp relay server

echo smtp.sendgrid.net username:password > /opt/zimbra/conf/relay_password


3. Export it to postfix

postmap hash:/opt/zimbra/conf/relay_password


4. Check the credentials are saved properly

postmap -q smtp.sendgrid.net /opt/zimbra/conf/relay_password


5. Setup SASL to use smtp relay authentication Continue reading Zimbra & Sendgrid SMTP Setup