fail2ban I’m using fail2ban to block script kiddies. Here is one line what you will find in your auth.log May 11 05:32:14 srv01 sshd[79609]: Invalid user postgres from 37.49.226.178 port 46504 This description can help you how to install and configure fail2ban I will update this post with new infos. Installation - Ubuntu / Debian sudo apt-get update sudo apt-get upgrade sudo apt-get install fail2ban Installation FreeBSD sudo pkg install py37-fail2ban Configuration Configuration Ubuntu / Devian cd /etc/fail2ban sudo vi jail. Read more

macOS and the X Window System If you want to use the X Window System on macOS, you need XQuartz. Install XQuartz brew cask install xquartz After a Reboot you will get the $DISPLAY set correctly. If you want to set it without a reboot see Start XQuartz temprorary Test with xeyes /opt/X11/bin/xeyes SSH X11Forwarding You can now use ssh -X or ssh -Y Uninstall brew cask uninstall xquartz Start XQuartz temprorary This is only necessary if you want to start XQuartz without a reboot. Read more

Goodbye Ghost Its time to say goodbye to the software I’ve used for long time to blog here. Ghost was a perfect piece of software when I started (again). I’ve learned a lot during that time, e.g. Markdown, configuring NGINX to serve data from Ghost. And how to get nodejs running on my server (which is not that easy as it sounds. more later…) Why? The problems I’ve had: It relies on nodejs - especially at the beginning, there had been some restrictions with the versions. Read more

Even with all the restrictions of today some people need to run macOS Server (mojave 5.7.1). With the availability of letsencrypt it is possible to use this server with a proper signed certificate instead of a self-signed certficate. I am using cloudflare-dns. With some changes you can use this also for other methods. This is a tutorial and scripts to install letsencrypt, get a certificate an renew it. Use it on your own risk! Read more

Fatal Error My Docker on macOS doesn’t start anymore. It shows the following At the very last line, you can see the following Error Message: no space left on device Disk full? Of course there is enough space on my local drive available, but the Docker disk image see FAQ is full. The disk image is located here ~/Library/Containers/com.docker.docker/Data/com.docker.driver.amd64-linux/Docker.qcow2 With the qcow-tool you can check it: $ /Applications/Docker.app/Contents/MacOS/qcow-tool info Docker.qcow2 ((version Three) (backing_file_offset 0) (backing_file_size 0) (cluster_bits 16) (size 68719476736) (crypt_method None) (l1_size 128) (l1_table_offset ((bytes 131072) (is_mutable false) (is_compressed false))) (refcount_table_offset ((bytes 65536) (is_mutable false) (is_compressed false))) (refcount_table_clusters 1) (nb_snapshots 0) (snapshots_offset 0) (additional (((dirty true) (corrupt false) (lazy_refcounts true) (autoclear_features 0) (refcount_order 4)))) (extensions ((Feature_name_table (((ty Incompatible) (bit 0) (feature Dirty)) ((ty Incompatible) (bit 1) (feature Corrupt)) ((ty Compatible) (bit 0) (feature Lazy_refcounts))))))) Okay, looks good so far! Read more