awk tutorilal

To print n'th column only of a file, ie print only specific field
eg
awk '{print $3,$6;}' myresult.txt


awk '{print $4;}' testPhone

when not able to download using git

git config --global http.sslverify false

To list all users in the zimbra groups

zmprov gdl  mygroup-all@mydomain.com

To check the port open

netstat -nan | grep portno

lsof -i -n -P | grep portno

nmap -sS -O IPadrees

Erlang installation on Ubuntu

Install the pre - requisite  for erlang installation by

apt-get -y install build-essential m4 libncurses5-dev libssh-dev unixodbc-dev libgmp3-dev libwxgtk2.8-dev libglu1-mesa-dev fop xsltproc default-jdk

Download the src code, untar it
and do
./cofigure
make
sudo make

One liner to stop / remove all of Docker containers:

One liner to stop / remove all of Docker containers:

docker stop $(docker ps -a -q)
docker rm $(docker ps -a -q)

Package Manager & Update Manager problems

Some time when you do "apt-get update"  you get error of key missing, you can solve it by  adding the key
eg
sudo apt-key adv --keyserver keyserver.ubuntu.com --recv-keys CBCB082A1BB943DB


sudo apt-key adv --keyserver keyserver.ubuntu.com --recv-keys MISSINFKEYTYPEEHERE