linux

Use find (1) as a quick and dirty duplicate file finder

Run the following two commands in bash to get a listing of all duplicate files (from a directory or location). This can help you clean out duplicate files that sometimes accumulate over time. The first command uses find to print all files (and specific attributes) from a specific location to a file, prefixing the size of the file in the name. This way all files with the same filename and… Read More »Use find (1) as a quick and dirty duplicate file finder

Save data from your broken Raspberry Pi SD card with GNU ddrescue

This week my Pi stopped working. After hooking up a monitor I saw kernel errors related to VFS. So the file system was obviously broken. Oops. The end conclusion is that the SD card is physically ‘broken’, but I still managed to salvage my data — which is more important than the card. Here’s how. Broken file system: fsck or dd? What didn’t work for me, but you might want… Read More »Save data from your broken Raspberry Pi SD card with GNU ddrescue

Linux server principles

This is a list, in no particular order, of principles to adhere when running a secure Linux server. SSH – Never allow direct SSH root access (set PermitRootLogin No). SSH – Do not use SSH keys without a passphrase. SSH – If possible, do not run SSH on a public IP interface (preferably use a management VLAN). SSH/SSL – Use strong SSH ciphers and MAC algorithms (Check with https://testssl.sh/). Never… Read More »Linux server principles

Just for Fun: The Story of an Accidental Revolutionary

This book had been sitting on my to-read list for way too long! But I finally found a second hand copy, so here we go! You could say this is the official autobiography of Linus Torvalds, the creator of Linux. The Operating System that changed the world! You can wake me up in the middle of the night to talk about operating systems. So this book is right up my… Read More »Just for Fun: The Story of an Accidental Revolutionary