Category: tcp

Technology Blog

Asus Router with Merlin Firmware External Network Interface Alias How To

Asus Router with Merlin Firmware External Network Interface Alias for Cable Modem Management The external network interface alias is used for obtaining direct access to the cable modem’s management interface when the modem is in bridge modem. A reason for this would be if the cable providers network has some sort of issue that causes…
Read more

Site to Site VPN using Asus Merlin Router and Unifi USG-Pro4

Site to Site VPN using Asus Merlin Router and Unifi USG-Pro4 I decided recently to replace my Asus RT-N66U. It served me well over many years but I had become frustrated that Asus had stopped patching and maintaining the firmware. I also noticed over time strange things would occur at times with the Asus Router.…
Read more

Router to Router VPN Tunnel using Asus Routers

Router to Router VPN Tunnel using Asus Routers Over the past few years I’ve tried a few times to successfully configure a Router to Router VPN tunnel using Asus Routers. In all the articles online something always was missing. So I figured this was a good article to write about. I currently have a tunnel…
Read more

Hadoop and ip_conntrack: table full, dropping packet

I’m pretty sure many folks have seen this specific error across multiple different linux systems specifically when iptables is enabled and the OS has thousands of connections coming in second. In my case I ran into this Examples of this are with Hadoop NameNode. Someone accidentally executed iptables -L to try to get a list…
Read more

Hadoop and Redhat System Tuning /etc/sysctl.conf

Hadoop and Redhat System Tuning /etc/sysctl.conf One of the most overlooked things after building out a Hadoop cluster is the operating system tuning. This post will cover how to tune settings in /etc/sysctl.conf also known as Linux Kernel Settings. /etc/sysctl.conf ## ALWAYS INCREASE KERNEL SEMAPHORES especially IF using IBM JDK with SharedClassCache also a separate…
Read more

Why now?

GS Tech Blog What is the GS Tech Blog! It’s a place for me to rant and provide my thoughts about technology I’ve worked with over many years. So after working as a Technology Systems Engineer for almost 20 years, I decided it’s time to create a blog to publish some of my ideas and…
Read more