You can also have a look on below checklist for security and optimization of your server :
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Security Software Installations
Complete Server Setup, and NS configuration.
CSF firewall installation.
Installing Mod-Security with Advanced Rules
Installing Clamav Anti Virus (Integrating Exim)
Installing Maldet ( Malicious Code Removal Software )
System Optimization and Hardening
Lockdown & Hardening the Root Password
Secure SSHD Port
sysctl.conf Hardening
host.conf Hardening
Network Security with hosts.allow & hosts.deny
nsswitch.conf Hardening
Enable DDOS Protection
Root Login Email Notifications
Noexec, Nosuid Temporary Directories (noexec Directories such as /tmp, /var/tmp, /dev/shm)
Security Updates as released by OS and/or Control Panel
Securing Services
Disable Unwanted Services
Securing DNS
Securing MySQL
Enable PHP Open_Basedir Protection
Enable mod_userdir Protection
Securing Console Access
PHP5 Hardening
Configuring Anti-Spam Features to Reduce Spam ( Enable RBL ACLs, SPF Protection, & Spam Assassin Configurations )
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