Disable ping response in Linux

sysctl -w net.ipv4.icmp_echo_ignore_all=1

http://www.linuxarticles.org/2010/10/disable-ping-response-in-linux/

Install mongodb on Ubuntu

1. import public key

sudo apt-key adv --keyserver keyserver.ubuntu.com --recv 7F0CEB10

2. create /etc/apt/sources.list.d/10gen.list

deb http://downloads-distro.mongodb.org/repo/ubuntu-upstart dist 10gen

3.

sudo apt-get update

4.

sudo apt-get install mongodb-10gen

Reference: http://docs.mongodb.org/manual/tutorial/install-mongodb-on-debian-or-ubuntu-linux/

tsocks

1. install epel first
http://fedoraproject.org/wiki/EPEL
1. insatll tsocks

yum install tsocks

2. add file /etc/tsocks.conf

server = 127.0.0.1
server_type = 5
server_port = 1234

3. establish ssh tunnel

ssh -D 1234 user@xxx.remote.host

4. wget with socks proxy

tsocks wget http://get.something

5. you might want to unset the http_proxy variable

unset http_proxy