Zertrin's Wiki

apt

Anonymous (anonymous@undisclosed.example.com) — 2020-04-29T06:09:45+00:00

APT Find reverse dependencies concise list, appropriate for programmatic approaches apt-cache rdepends packagename apt-cache rdepends --installed packagename more details on the type of dependancy apt rdepends packagename more hunam output, focus on installed packages

git

Anonymous (anonymous@undisclosed.example.com) — 2020-04-29T06:19:51+00:00

git Useful submodule foreach commands List current HEAD commit in each submodule git submodule foreach 'git rev-parse HEAD' List current checked-out branch in each submodule git submodule foreach 'git rev-parse --abbrev-ref HEAD' Batch remote management in submodules

linux_bitlocker_automount

Anonymous (anonymous@undisclosed.example.com) — 2025-12-10T16:51:22+00:00

The answer below describes how to mount a BitLocker partition under Linux without using dislocker. Instead, it uses cryptsetup and achieves full auto-mount capability. For security, the partition where /etc/cryptsetyp-keys.d lives should itself be encrypted at rest. In my setup, this is the case as the root partition is LUKS-encrypted, with the unlocking occurring during boot via a passphrase.

linux_file_acl

Anonymous (anonymous@undisclosed.example.com) — 2017-10-02T03:15:44+00:00

Linux File ACL Copying the ACL of one file to another: getfacl file1 | setfacl --set-file=- file2 Copying the access ACL into the Default ACL: getfacl --access dir | setfacl -d -M- dir

linux_file_permissions

Anonymous (anonymous@undisclosed.example.com) — 2015-04-30T10:30:55+00:00

This is an archive of the Slicehost article located at This article is NOT licensed under CC Attribution-Share Alike 3.0 Unported. Linux file permission concepts Linux file permissions are strange and wondrous things. Start down the path of understanding by looking at the core concepts behind them before moving on to practical applications.

lxd

Anonymous (anonymous@undisclosed.example.com) — 2019-05-30T08:36:07+00:00

LXD Setup base ubuntu container with zsh to reuse as base image sudo apt-get update && sudo apt-get install --no-install-recommends -y sudo aptitude git zsh htop vim-nox screen ccze coreutils tree less mc stow python-pip ack-grep powerline ncdu && sudo apt-get clean && sudo rm -rf /var/lib/apt/lists/* /tmp/* /var/tmp/* git clone git://github.com/robbyrussell/oh-my-zsh.git ~/.oh-my-zsh cp ~/.oh-my-zsh/templates/zshrc.zsh-template ~/.zshrc sudo chsh -s /bin/zsh ubuntu

misc_tricks

Anonymous (anonymous@undisclosed.example.com) — 2019-05-30T06:57:14+00:00

Miscellaneous tricks This is a collection of Miscellaneous tricks that I encountered and wanted to archive here. Favicon as Base64 From Convert your image file to Base64 string with a tool like this and then replace the YourBase64StringHere placeholder in the below snippet with your string and put the line in your

ntp

Anonymous (anonymous@undisclosed.example.com) — 2012-11-04T13:42:13+00:00

Fixing NTP Refusing to Sync Article from Petr Baudiš () under Creative Commons Attribution-ShareAlike 3.0 Unported License. April 26th, 2010 I have just been confronted by NTP absolutely refusing to touch my system’s clock. The trouble with NTP is that it is absolute PITA to debug it at all since when it does not get in sync with its peers, it goes at great lengths to make its reasons as incomprehensible as possible.

openvpn

Anonymous (anonymous@undisclosed.example.com) — 2015-03-12T08:37:43+00:00

OpenVPN Links to useful documentation Manpage HOWTO Subnet topology Windows TAP Drivers Lans behind OpenVPN Bridging vs. routing

postgresql

Anonymous (anonymous@undisclosed.example.com) — 2015-07-27T09:13:44+00:00

PostgreSQL This is a collection of PostgreSQL tricks that I encountered and wanted to archive here. Reset database to original state (initdb) on Windows rem ### ------------------------------------------------------------- ### rem ### v v v v v v v v v v v BEGIN CONFIG v v v v v v v v v v v v ### set "postgres_path=C:\PostgreSQL\9.4" set local_postgres_pass=REPLACEME set local_superuser=REPLACEME_admin set local_superuser_pass=REPLACEME set local_port=5434 rem ### ^ ^ ^ ^ ^ ^ ^ ^ ^ ^ ^…

python

Anonymous (anonymous@undisclosed.example.com) — 2015-08-11T07:22:49+00:00

Python tips and tricks This is a collection of Python tips and tricks that I encountered and wanted to archive here. See older versions of package on PyPi From It's perhaps a little inelegant, but it appears that you can go to the URL https://pypi.python.org/simple/

screen_quick_reference

Anonymous (anonymous@undisclosed.example.com) — 2016-02-16T21:37:12+00:00

Document mirrored from under following licence: GNU General Public License 2.0 or later screen Quick Reference Getting in start a new screen session with session name screen -S list running sessions/screens screen -ls attach to a running session screen -x ... to session with name

start

Anonymous (anonymous@undisclosed.example.com) — 2025-12-10T16:33:36+00:00

zertrin.org * sysadmin * bootstrap-script Pages * APT * Git * Linux file permission concepts * Linux file ACLs * Linux BitLocker auto-mount (with cryptsetup) * KVM * LXD * NTP * OpenVPN * PostgreSQL * Python * Screen Quick Reference * Windows Batch Scripting * Windows tricks * Misc tricks Other * private

windows_batch_scripting

Anonymous (anonymous@undisclosed.example.com) — 2015-08-04T12:18:42+00:00

Windows Batch Scripting The Wikibook Tricks How to find if a string is in a list of strings in a DOS batch file from setlocal EnableDelayedExpansion set arg[1]=validArgument1 set arg[2]=validArgument2 set arg[3]=validArgument3 for /L %%i in (1,1,3) do if /I "%1" equ "!arg[%%i]!" SET "ARG=!arg[%%i]!"

windows_tricks

Anonymous (anonymous@undisclosed.example.com) — 2016-11-20T21:22:51+00:00

Windows tricks This is a collection of Windows tricks that I encountered and wanted to archive here. Program doesn't work for normal user's accounts From If your game or application works with admin accounts, but not with limited accounts, you can fix it to allow limited users to access the program files folder with