You need to swich from bios to efi? Read on. DISCLAIMER: you need to be familiar with these commands and make sure you have backup because you may destroy your linux if you do not pay attention.

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In this article I will show you how to create and set up a syslog-ng in docker container and redirect logs from another container to it. You should have already a running docker set up. If you do not know how to do that, do a search on this page as I have created several articles for it. Also, web is full of it.

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I have recently switched to a retina Macbook pro and screen wise, some things are totally different there. Like this situation where guest window of a virtualbox machine is so small that you cannot use it. So small than it is close to the preview thumbnail from VirtualBox manager.

In order to fix this, you need to go to the VirtualBox Preferences » Display and change the Scale Factor to at least 200%.

On a Macbook pro with Retina display you cannot get to native resolution in the system settings. For example, on Macbook Pro 16 inch, the native resolution is 3072x1920 but the maximum available scaled resolution is 2048x1280. The reason is on the native resolution everything looks very tiny on this small screen. Of course, this doesn't mean you cannot get to that resolution. There are few tools on the internet that can achieve this but what I have been using for this is a command line tool called cscreen.

So, you have a mac computer with touch id and you would like to use it also when you do "sudo su -" on Terminal but there is no menu to let you set up this. You actually can, via Terminal :) PS: there is one small downside. You need to do this after each OS upgrade. But since it doesn't happen so often and the procedure is very simple, I am ok with it.

1. Become root with sudo command (you will have to type the password this time):

fmbpro:~ florian$ sudo su -
Password:
fmbpro:~ root# 

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Let's say you are in my situation: you have bought recently a new mac, with Catalina (10.15) and you are switching from an older one that was supporting only High Sierra (10.13). And you get this error when trying to do sudo port selfupdate.

fmbpro:~ florian$ sudo port -v selfupdate
Password:
Error: Current platform "darwin 19" does not match expected platform "darwin 17"
Error: If you upgraded your OS, please follow the migration instructions: https://trac.macports.org/wiki/Migration
OS platform mismatch
    while executing
"mportinit ui_options gl

You try to start your docker container with limits for memory and you get this warning:

Your kernel does not support swap limit capabilities or the cgroup is not mounted. Memory limited without swap.

At this point, I assume you have already cgroup working, CPU and RAM is limited and only swap is left. These steps were done on Debian Buster.

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How to start services in certain order with Systemd? Have been reading a bunch of documentation to figure this one out. By the way, this also includes the SysV startup scripts (which are called by systemd). So, in this below example (real situation), I have Docker that needs ocfs2 filesystem which runs on top of DRBD. Default startup configuration was not quite ok because docker almost always started first and ocfs2 was started in the same time with drbd and failed to mount the ocfs2 filesystem. The error was:

mount.ocfs2: I/O error on channel while opening device /dev/drbd0

Remember this article? https://tar.gz.ro/linux-backup-restore.html Linux is powerful and whatever linux based, is powerful too. Cygwin can help you in many ways and in this article I will explain how easy is to clone an entire disk with it. Proprietary and costly applications? HA! :) !!! WARNING !!! >>> DO THIS VERY CAREFUL BECAUSE WRONG CHOICES CAN DESTROY DATA <<< !!!

Ever wonder how to connect via ssh to a windows machine? Of course there are other ways but I like this one better because it allows you to access the most powerful tool ever created for Windows: cygwin :) So, here we go.

1. Run cygwin as administrator

Right click on the cygwin icon and select "Run as administrator".

2. Execute the command ssh-host-config:

Assuming this is the first time, you should answer yes to all questions. Also, when prompted to "Enter the value of CYGWIN for the daemon", type 'ntsec'.