Hong's Tech Blog

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Leong Hean Hong

The blog is older than you know. I prefer counting from the emergence of one integral anomaly to the emergence of the next, in which case this is the 4th version.

Setup Fortinet VPN Client In CentOS 7

My applications need to access services in client's private network. I am using openfortivpn to connect to Fortigate SSL VPN server. It should work for PPP VPN too. Installation Checkout https://github.com/adrienverge/openfortivpn#installing for inst...

Unban IP In Fail2ban

Fail2Ban is an intrusion prevention software framework that protects computer servers from brute-force attacks. Source: https://en.wikipedia.org/wiki/Fail2ban Fail2ban detects repeated failed logins, and bans the IP address. Subsequent attempt to es...

OpenSSL Common Usage

OpenSSL is a powerful Linux command for managing certificates. These are some common operations I frequently use. Generate RSA Key Pair This command generates a 2048 bits private key. openssl genrsa -out example.key 2048 Verify private and public ke...

Installing Netezza Client and ODBC Driver In CentOS 7

IBM Netezza is a data warehouse appliance. It partially supports SQL-92 (SQL/2). Unfortunately the software is proprietary. Besides the limited articles on IBM Knowledge Center, it is quite hard to find help on the Stack Overflow. This is how I setup...

Auto-restart Crashed Systemd Service

Systemd is a system and service manager for Linux operating systems. It is designed to be backward compatible with SysV init scripts, and provides a number of features such as parallel startup of system services at boot time, on-demand activation of ...