Incremental banning with Fail2Ban

Fail2Ban is a useful tool to keep bad traffic away from your server or VPS. It scans log files for suspicious entries (like failed password entries for SSH logins) and can ban the IPs of these attackers automatically. Naturally if a bot from a certain IP continues to attempt to attack your server or VPS, […]

Fixing a Let’s Encrypt certificate renewal error

So just a moment ago I was wondering why my Let’s Encrypt certificate on a particular server wasn’t renewing. I’m using a simple script called acme-tiny for Let’s Encrypt as it’s just about the lightest implementation for it.  However it failed with this error message: Traceback (most recent call last): File “/home/user/”, line 198, in […]

Let’s Encrypt intermediate certificate change

I checked one of the sites I use Let’s Encrypt free SSL certificates on SSL Labs’ SSL Test recently and found to my dismay that they only got a “B” grade while I was pretty sure I got an “A” grade before. Looking at the details it showed the intermediate certificate chain to be incomplete […]

Enabling http/2 on your sites with Ubuntu and nginx

HTTP is the most important protocol on the web, but hasn’t had a major update in a long time (HTTP 1.1 was introduced in 1997). In May 2015 however the HTTP 2.0 (HTTP/2) standard was published. The new standard promises increased speed. As of right now http/2 will only work on HTTPS sites. Although the […]

Getting snmpd to work through IPv6

I have Cacti installed so that I have pretty graphs (CPU/load/memory/disk/network) for all my servers (VPS) in one place. I just enabled full IPv6 on one of them and Cacti stopped working. The problem wasn’t Cacti though, it was the server it was now trying to contact through IPv6. As I only need SNMP for […]