Hello Everyone, I am a newbie in Linux and I really need a tutorial/help for doing this. I have CentOS 5.5 32 bits in Master/Slave Servers 1. For Master Server: I want to speed Up Postfix Mail Server with PowerDNS like http://postfixmail.com/blog/index.php/speed-up-your-mail-server/ I do not know how to do it with PowerDNS. I mean, I want to have "caching-nameserver" with localhost recursion. But I want to deny recursion to external clients. 2. Set up 2 servers master/slave with PowerDNS (With MySQL Backend) And Poweradmin with database replication with ssl encryption http://www.howtoforge.com/how-to-set-up-mysql-database-replication-with-ssl-encryption-on-centos-5.4 http://www.howtoforge.com/installing-powerdns-with-mysql-backend-and-poweradmin-on-centos-5.2 Can those tutorials "work" together to do it? 3. iptables configuration 3.1 I have iptables in Master/Slave Servers. How to configure iptables to work with MySQL database replication with ssl encryption? 3.2. In order to allow remote client to connect the DNS Servers, Should I add the following lines on /etc/sysconfig/iptables -A RH-Firewall-1-INPUT -m state --state NEW -p udp --dport 53 -j ACCEPT -A RH-Firewall-1-INPUT -m state --state NEW -p tcp --dport 53 -j ACCEPT 4. How can I add a second slave server with MySQL database replication with ssl encryption? I mean 3 DNS servers: Master/Slave1/Slave2 5. Can I have PowerDNS and Bind in the same Master Server? I mean, 5.1. speed Up Postfix Mail Server with Bind caching-nameserver 5.2. Master DNS with PowerDNS Thanks for all your help.