Webmin, Virtualmin and APT for Ubuntu and Debian
I often use Webmin and Virtualmin to manage basic stuff on Linux servers, mostly so because others sometime need to change minor settings on these servers, and they may or …
Sysadmin
Forcing apt-get to use IPv4
When or if you run into trouble with apt-get and IPv6 connections timing out or not resolving properly at all, it may be a good idea to simply prevent apt-get …
URL re-writing with nginx, PHP, and WordPress
There are many posts about nginx, re-directs, PHP, and WordPress. There are somewhat fewer posts that talk about (internal) re-writes, where the request by the web browser is mangled to …
What’s My IP / Dynamic DNS / DDNS / DynDNS
There are a number of ways to figure out your current public IP address automatically, which can be extremely useful for Dynamic DNS (DDNS) situations or other automation ventures, here …
Changing your MTU may help certbot / Let’s Encrypt
While attempting to create a Let’s Encrypt SSL certificate using certbot for a number of domains, I ran into something that appeared to be a timeout issue in the certbot …
Things to do after migrating to Zimbra 8.8.x
As I recently handled a migration from Zimbra 8.7.11 to Zimbra 8.8.12, I’ve been running into things I think the Zimbra updater should handle by itself, and/or things that should …
Using sfdisk to recover a partition table on Linux
As he re-entered the sfdisk dump manually in the remote recovery console, using the devil’s editor (vi), he was silently thanking the Linux developers for not screwing around with the …
Using nmap to “ping” remote ports
nmap -p 443 site.com nmap -p 21,22,2222,80,443 site.com nmap -p 50-100 site.com nmap is a very versatile tool for analyzing remote hosts. Given the above examples, nmap will return the …
Show which process/program is listening to what port using netstat and lsof
lsof -Pnl +M -i4 lsof -Pnl +M -i6 or netstat -tulpn netstat -npl There are obviously a number of ways to accomplish this, but these variations will cover a lot …
Using MTR to create a text file report
mtr –report –report-cycles 20 www.instagram.com > ignetrpt.txt The above should be entered on one line. Using MTR this way makes it easy to simply send a trace report via e-mail. …