Introduction
Some things are just hard to remember. Nasty moment comes when you have to do something but you just do not remember the right order. These are my weak points. All tested on Ubuntu 14.04 LTS.
Miscellaneous
tar: create – full backup of /, dont tar /mnt
$ sudo tar -cvpzf backup.tar.gz –exclude=/mnt /
tar: extract – backup extracted to /recover folder
$ sudo tar -xvpz backup.tar.gz -C /recover
Edit crontabs
$ crontab -e
rsync
todo
grep: find out how to enable php scripts in user directories with apache
$ sudo grep -r ‘user directories’ /etc/apache2/*
Iptables stuff
iptables accept or drop all
$ sudo iptables -P INPUT ACCEPT // DROP
iptables list rules fast
$ sudo iptables -L -n
iptables format rules
$ sudo iptables -F
iptables accept by port
$ sudo iptables -I INPUT -s 0.0.0.0/0 -p tcp –dport 80 -j ACCEPT
iptables accept by ip
$ sudo iptables -I INPUT -s 172.28.0.0/255.255.0.0 -j ACCEPT
Iptables stateful firewall
$ sudo iptables -I INPUT -m conntrack –ctstate ESTABLISHED,RELATED -j ACCEPT
show system variables
$ $PATH
Give sudo
$ usermod -a -G sudo exampleuser
ssh-keypair on serverside
$ ssh-keygen //follow steps
$ mv id_rsa.pub .ssh/authorized_keys
$ chown -R example_user:example_user .ssh
$ chmod 700 .ssh chmod 600 .ssh/authorized_keys
Puppet test gatalog on node do not operate
$ sudo puppet agent – -test – -noop
perl: warning: Please check that your locale settings FIX
$ export LC_ALL="en_US.UTF-8"
Send email from shell
$ echo ‘message’ | mail -s “subject” -a “From: yourname@example.com” -A example-attachment receiveremail@example.com
mysql (create database, user and grant privileges)
CREATE DATABASE dbname;
USE dbname;
GRANT ALL ON dbname.* TO ‘dbuser’@’localhost’ IDENTIFIED BY ‘password’;
FLUSH PRIVILEGES;
References
Eli The Computer Guy tar backup