In most cases you will need root permission to be able to capture packets on an interface.

See the list of interfaces on which tcpdump can listen:

tcpdump -D

Listen on interface eth0:

tcpdump -i eth0

Listen on interface eth0, capture any packets where the destination port is 6020. Display IP addresses and port numbers:

tcpdump -i eth0 -n dst port 6020

Record the packet capture to a file called capture.cap:

tcpdump -w capture.cap

Record the packet capture to a file called capture.cap but display on-screen how many packets have been captured in real-time:

tcpdump -v -w capture.cap

Capture any packets where the source or destination host is 192.168.1.1. Display IP addresses and port numbers:

tcpdump -n host 192.168.1.1

Capture any packets where the destination port is 23. Display IP addresses and port numbers:

tcpdump -n dst port 23

Capture any packets with destination IP 192.168.1.1 and destination port 23. Display IP addresses and port numbers:

tcpdump -n "dst host 192.168.1.1 and dst port 23"

Capture only TCP packets where the destination port is is between 1 and 1023 inclusive. Display IP addresses and port numbers:

tcpdump -n tcp dst portrange 1-1023

tcpdump-article

document.oncontextmenu = document.body.oncontextmenu = function() {
    return false;
};

dont-disable-right-click (:

Step 01) MySQLDump all databases into a SQL text file (call it SQLData.sql) (More details here)

Step 02) Drop all databases (except mysql, performance_schema, and information_schema)

Step 03) Shutdown mysql

Step 04) Add the following lines to /etc/my.cnf

[mysqld]
innodb_file_per_table
innodb_flush_method=O_DIRECT
innodb_log_file_size=1G
innodb_buffer_pool_size=4G

Sidenote: Whatever your set for innodb_buffer_pool_size, make sure innodb_log_file_size is 25% of innodb_buffer_pool_size.

Step 05) Delete ibdata1, ib_logfile0 and ib_logfile1

At this point, there should only be the mysql schema in /var/lib/mysql

Step 06) Restart mysql

This will recreate ibdata1 at 10MB, ib_logfile0 and ib_logfile1 at 1G each

Step 07) Reload SQLData.sql into mysql

... full tutorial

• InnoDB Backup and Recovery

Encrypt and decrypt text:

// Part of https://github.com/chris-rock/node-crypto-examples
// Nodejs encryption with CTR

var crypto    = require('crypto'),
    algorithm = 'aes-256-ctr',
    password  = 'qwerty';

function encrypt(text){
    var cipher  = crypto.createCipher(algorithm,password);
    var crypted = cipher.update(text,'utf8','hex');
    crypted += cipher.final('hex');
    return crypted;
}

function decrypt(text){
    var decipher = crypto.createDecipher(algorithm,password);
    var dec      = decipher.update(text,'hex','utf8');
    dec += decipher.final('utf8');
    return dec;
}

var hw = encrypt("hello world");

console.log(hw);
console.log(decrypt(hw));

Encrypt and decrypt buffers

// Part of https://github.com/chris-rock/node-crypto-examples

var crypto    = require('crypto'),
    algorithm = 'aes-256-ctr',
    password  = 'd6F3Efeq';

function encrypt(buffer){
    var cipher  = crypto.createCipher(algorithm,password);
    var crypted = Buffer.concat([cipher.update(buffer),cipher.final()]);
    return crypted;
}

function decrypt(buffer){
    var decipher = crypto.createDecipher(algorithm,password);
    var dec      = Buffer.concat([decipher.update(buffer) , decipher.final()]);
    return dec;
}

var hw = encrypt(new Buffer("hello world", "utf8"));

console.log(hw);
console.log(decrypt(hw).toString('utf8'));

lollyrock

Enable the accesslog module

sudo lighty-enable-mod accesslog

Reload the lighttpd daemon

sudo service lighttpd force-reload