rm -rf /

by NeQuissimus

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Project maintained by NeQuissimus Hosted on GitHub Pages — Theme by mattgraham

Fix gigantic Zoom windows

(Aug 28, 2020)

Linux, Zoom

nano ~/.config/zoomus.conf

Change autoScale=true to autoScale=false

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Ad blocking on Mikrotik router

(Apr 25, 2017)

RouterOS

/system script add name="Squid_Blacklist" source="/tool fetch url=\"http://www.squidblacklist.org/downloads/tik-dns-ads.rsc\" dst-path=ads.rsc; /import file-name=ads.rsc;"

/system scheduler add comment="Squid_Blacklist" interval=1d name="DownloadSquidBlacklist" on-event=Squid_Blacklist start-date=jan/01/1970 start-time=20:00:00

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Wildcards in SSH known_hosts

(Oct 4, 2016)

Linux, OSX

github.com,192.30.252.*,192.30.253.*,192.30.254.*,192.30.255.* ssh-rsa AAAAB3NzaC1yc2EAAAABIwAAAQEAq2A7hRGmdnm9tUDbO9IDSwBK6TbQa+PXYPCPy6rbTrTtw7PHkccKrpp0yVhp5HdEIcKr6pLlVDBfOLX9QUsyCOV0wzfjIJNlGEYsdlLJizHhbn2mUjvSAHQqZETYP81eFzLQNnPHt4EVVUh7VfDESU84KezmD5QlWpXLmvU31/yMf+Se8xhHTvKSCZIFImWwoG6mbUoWf9nzpIoaSjB+weqqUUmpaaasXVal72J+UX2B+2RPW3RcT0eOzQgqlJL3RKrTJvdsjE3JEAvGq3lGHSZXy28G3skua2SmVi/w4yCE6gbODqnTWlg7+wC604ydGXA8VJiS5ap43JXiUFFAaQ==

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List options current kernel was compiled with

(Sep 14, 2016)

Linux

zcat /proc/config.gz

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Largest MySQL tables

(Aug 12, 2016)

MySQL

SELECT CONCAT(table_schema, ".", table_name),
CONCAT(ROUND(table_rows / 1000000, 2), "M") rows, 
CONCAT(ROUND(data_length / ( 1024 * 1024 * 1024 ), 2), "G") DATA, 
CONCAT(ROUND(index_length / ( 1024 * 1024 * 1024 ), 2), "G") idx, 
CONCAT(ROUND(( data_length  + index_length ) / ( 1024 * 1024 * 1024 ), 2), "G") total_size, 
ROUND(index_length / data_length, 2) idxfrac 
FROM information_schema.TABLES 
ORDER BY data_length + index_length DESC 
LIMIT 10;

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Screen to open serial connection

(Apr 13, 2016)

Linux

screen /dev/ttyUSB0 9600

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Keep processes running beyond Jenkins job

(Apr 11, 2016)

Jenkins

In Jenkins job:

export BUILD_ID="dontKillMe /usr/bin/vagrant"

See https://wiki.jenkins-ci.org/display/JENKINS/ProcessTreeKiller

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Set JAVA_HOME from PATH

(Apr 05, 2016)

Java, Linux

export JAVA_HOME="${$(readlink -e $(type -p java))%*/bin/java}"

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Disable CAPS LOCK

(Apr 04, 2016)

Linux

setxkbmap -option ctrl:nocaps

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Get all patch files for Git revisions

(Nov 19, 2015)

Git

$ export N=100; for i in $(git log --abbrev-commit --format=format:'%h' --all  ${FILE}); do N=$((N+1)); git diff "${i}^..${i}" > ${N}-${i}.patch; done

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Run specific tests in Maven

(Nov 19, 2015)

Maven

$ mvn test -Dtest=com.nequissimus.*Test

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Environment variables for a PID

(Aug 26, 2015)

Linux

$ cat /proc/${PID}/environ

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Revert ESXi snapshot from the CLI

(Aug 25, 2015)

ESXi, VMware

$ vim-cmd vmsvc/getallvms

VMID is the first column

$ vim-cmd vmsvc/snapshot.get ${VMID}

Find snapshot ID

$ vim-cmd vmsvc/snapshot.revert ${VMID} ${SNAPID} false

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Grab images from Instagram app

(Mar 31, 2015)

Android

$ adb root
$ mkdir ~/Downloads/instagram
$ adb pull /data/data/com.instagram.android/cache ~/Downloads/instagram
$ find ~/Downloads/instagram -name '*.0' -exec mv {} {}.jpg \;
$ open ~/Downloads/instagram

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Show Mac CPU model

(Feb 7, 2015)

OSX

$ sysctl -n machdep.cpu.brand_string
Intel(R) Core(TM) i7-3770S CPU @ 3.10GHz

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Run IntelliJ IDEA without Java 1.6

(Dec 30, 2014)

Java, OSX

• Open /Applications/IntelliJ\ IDEA\ 14\ CE.app/Contents/Info.plist
• Find JVMVersion
• Change the value from 1.6* to 1.8*

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Find class file version

(Dec 15, 2014)

Java

$ od -x ~/dev/Test.class | head -1
0000000      feca    beba    0000    3200    4200    0007    073d    3e00

The 3200 signals JDK 1.6, 3100 would be 1.5 etc.

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Follow log files

(Dec 4, 2014)

Linux

find /var/log/ -name "*log" -type f -follow | xargs tail -n 0 -f | grep -v '^$'

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Change JVM from command line

(Nov 12, 2014)

Java, OSX

function setjdk() {
  if [ $# -ne 0 ]; then
    removeFromPath '/System/Library/Frameworks/JavaVM.framework/Home/bin'
    if [ -n "${JAVA_HOME+x}" ]; then
      removeFromPath $JAVA_HOME
    fi
    export JAVA_HOME=`/usr/libexec/java_home -v $@`
    export PATH=$JAVA_HOME/bin:$PATH
  fi
}

function removeFromPath() {
  export PATH="$(echo "$PATH" | sed -E -e "s;:$1;;" -e "s;$1:?;;")"
}

setjdk 1.9

Source

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MySQL prompt

(Nov 12, 2014)

MySQL

export MYSQL_PS1="\u@\d> "

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Single-line git commit history

(Jul 28, 2014)

git

git config --global alias.lg "log --graph --abbrev-commit --decorate --date=relative --format=format:'%C(bold blue)%h%C(reset) - %C(bold green)(%ar)%C(reset) %C(white)%s%C(reset) %C(dim white)- %an%C(reset)%C(bold yellow)%d%C(reset)' --all"

git lg

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Send plain-text messages via UDP

(Jul 24, 2014)

shell

echo "Test" | socat -u STDIO UDP-DATAGRAM:127.0.0.1:514

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Compare files with comm

(Jul 24, 2014)

shell

# First column: Lines unique to file1
# Second column: Lines unique to file2
# Third column: Lines common to both files
$ comm file1 file2

# Hide all columns (1, 2 & 3; which makes no sense!)
$ comm -123 file1 file2
 
# Only show common lines
$ comm -12 file1 file2

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Revert Subversion merge

(Apr 16, 2014)

Subversion

svn merge -c -REVISION .

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Send/Receive SNMP traps

(Sep 17, 2013)

OSX, Linux

~/.snmp/snmptrapd.conf

disableAuthorization yes
com2sec local     127.0.0.1/32    public
com2sec local     10.30.68.0/24   public
view all     included  .1

Start receiver

sudo snmptrapd -Lf ~/.snmp/output.txt

Send sample trap

sudo snmptrap -v 2c -c public -m ALL localhost "" SNMPv2-MIB::sysLocation.0 s s "Hello World"

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Change .NET framework in Powershell

(Sep 17, 2013)

Windows

<!-- The following should be saved in C:\Windows\System32\WindowsPowershell\v1.0\ (or the correct path to Windows Powershell)
 as a file named "powershell.exe.config" -->
<?xml version="1.0"?>
<configuration>
    <startup useLegacyV2RuntimeActivationPolicy="true">
        <supportedRuntime version="v4.0.30319"/>
        <supportedRuntime version="v2.0.50727"/>
    </startup>
</configuration>

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Path to .NET Framework

(Sep 17, 2013)

Windows

function Get-FrameworkDirectory {
  $([System.Runtime.InteropServices.RuntimeEnvironment]::GetRuntimeDirectory())
}

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Copy files with progress

(Sep 16, 2013)

OSX, Linux

alias cp='rsync --progress'

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Remove key from known_hosts

(Sep 16, 2013)

OSX, Linux

ssh-keygen -R HOST

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MySQL log

(Sep 16, 2013)

MySQL

my.cnf.51

log=/var/log/mysql/mysql.log

my.cnf.56

general_log=true
general_log_file=/var/log/mysql/mysql.log

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Prevent Spotlight indexing

(Mar 29, 2013)

OSX

touch /Volumes/MyDrive/.metadata_never_index

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List/Clear downloaded files list in OSX

(Jan 19, 2013)

OSX

List

sqlite3 ~/Library/Preferences/com.apple.LaunchServices.QuarantineEventsV2 'select LSQuarantineDataURLString from LSQuarantineEvent'

Empty

sqlite3 ~/Library/Preferences/com.apple.LaunchServices.QuarantineEvents* 'delete from LSQuarantineEvent'

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Rebuild context menu entries

(Aug 22, 2012)

OSX

/System/Library/Frameworks/CoreServices.framework/Versions/A/Frameworks/LaunchServices.framework/Versions/A/Support/lsregister -kill -r -domain local -domain system -domain user

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Limit bandwidth

(Apr 19, 2012)

OSX

Add

ipfw pipe 1 config bw 100KB
ipfw add 1 pipe 1 src-port any

Remove

ipfw delete 00001

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Headless VMware Fusion

(Feb 17, 2012)

OSX, VMware Fusion

/Library/Application\ Support/VMware\ Fusion/vmrun -T fusion start /Volumes/VMs/_Hadoop/Hadoop\ Master.vmwarevm/Hadoop\ Master.vmx nogui

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Hide/Show ~/Library

(Jul 21, 2011)

OSX

chflags [nohidden|hidden] ~/Library

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Force login via RDP

(Mar 11, 2011)

Windows

mstsc /v:123.123.123.123 /admin

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Blank Dock.app icon

(Feb 12, 2011)

OSX

defaults write com.apple.dock persistent-apps -array-add '{tile-data={}; tile-type="spacer-tile";}'
killall Dock

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Rebuild Spotlight index

(Oct 6, 2010)

OSX

sudo mdutil -E /

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Trigger OSX maintenance scripts

(Sep 21, 2010)

OSX

sudo periodic daily weekly monthly

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