screensaver openbox

1 – Install xscreensaver package

apt-get install xscreensaver

2 – Configure xscreensaver to run in openbox startup

vi .config/openbox/autostart

xscreensaver -no-splash &

3 – Configure keyboard sequence W-l to lock screen

vi .config/openbox/rc.xml
 <keybind key="W-l">
   <action name="Execute">
     <command>xscreensaver-command -lock</command>

*Restart Openbox to test


pidgin + ejabberd xmpp server

Server IP Address: - Domain:

1 – Install the packages: ejabberd pidgin

apt-get install ejabberd pidgin


2 – Add admin user ( user domain password )

ejabberdctl register admin passwordHere

3 – Configure user admin as admin

vi /etc/ejabberd/ejabberd.yml

change the line: - "": "localhost" in acl admin

         - "admin": ""

4 – Restart ejabberd service

/etc/init.d/ejabberd restart

5 – Access Web Admin interface of ejabberd

6 – Add new user

ejabberdctl register nickollas passwordHere

*You can add a new user on web interface in: Virtual Hosts => localhost => Users


7 – Open Pidgin

Accounts => Manage Accounts => Add

  Basic => 
    Username: nickollas
    Password: passwordHere

  Advanced =>
    Connect port: 5222
    Connect server:

wake on lan linux

Wake-on-LAN is an Ethernet networking standard that allows a server to be turned on by a network message. You need to send ‘magic packets’ to wake-on-lan enabled ethernet adapters and motherboards. WoL must be active in both: ethernet adapter and BIOS motherboard.

1 – Enable Wake-on-Lan on BIOS

2 – Install one Wake-on-Lan client. In Debian: etherwake. In CentOS: wol

apt-get install etherwake

3 – Send a network message to turned on a machine

etherwake 77:e5:49:f7:b7:c3

How to view if wake-on-lan is enabled on network adapter ( g [on] d [off] )*

ethtool eth0 | grep -i wake

*If the above command shows that wake-on-lan is disabled then maybe it is necessary to activate the same every time the machine starts.

– In some cases wake-on-lan is not active when the machine is turned on. Enable it in cron

crontab -e
@reboot /sbin/ethtool -s eth0 wol g

– Create a list with all mac addess of your network

nmap -sP && arp -a | sort -n -t . -k 4 | awk '{print "etherwake", $4, "#"$2}'

Some machines do not support Wake-on-LAN after a power failure. Use of an uninterruptible power supply (UPS) will give protection against a short period without power. A typical BIOS setting is AC back function which may be on, off, or memory. This last restores the machine to the state it was in when power was lost.

use etc hosts as dns server

Server configuration

Install dnsmasq

apt-get install dnsmasq

Add entries at end of the /etc/hosts

echo ' abc' >> /etc/hosts 

Start/Restart dnsmasq

/etc/init.d/dnsmasq restart

Client configuration

Put server’s IP in the /etc/resolv.conf

echo 'nameserver' > /etc/resolv.conf

Test the resolution names

nslookup abc