quyenlv

# Vncserver service file for Debian or Ubuntu with systemd
#
#  Install vncserver
#      apt-get install tightvncserver
#
# 1. Copy this file to /etc/systemd/system/vncserver@.service
# 2. Edit User=
#    e.g "User=jo"
# 3. Edit the vncserver parameters appropriately in the ExecStart= line!
#    e.g. the -localhost option only allows connections from localhost (or via ssh tunnels)

quyenlv

Install GIMP

sudo add-apt-repository ppa:otto-kesselgulasch/gimp
sudo apt-get update
sudo apt-get install gimp gimp-gmic

Install Photoshop theme

wget -O gimp-2.8.zip http://drive.noobslab.com/data/themes/gimp/gimp-2.8.zip

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Topology

+------------------+                    +----------------------+
|   Local host     |  tcpdump over ssh  |    Remote Host       |
|                  |--------------------|                      |\ eth0
| +--------------+ |--------------------|                      |/
| |   Wireshark  | |                    |  tcpdump -i eth0...  |

quyenlv

Topology

+------------------+                    +----------------------+
|   Local host     |  tcpdump over ssh  |    Remote Host       |
|                  |--------------------|                      |\ eth0
| +--------------+ |--------------------|                      |/
| |   Wireshark  | |                    |  tcpdump -i eth0...  |

quyenlv

Instructions

sysctl net.ipv4.ip_forward=1
iptables -t nat -A PREROUTING -p tcp -i eth0 --dport 12345 -j DNAT --to-destination 192.168.1.2:56789
iptables -t nat -A POSTROUTING -j MASQUERADE

Reference

• https://askubuntu.com/questions/320121/simple-port-forwarding

quyenlv

Just using this one-music-note command

sudo socat TCP4-LISTEN:12345,fork TCP4:192.168.1.2:56789

Or with UDP port:

sudo socat UDP-LISTEN:161,fork UDP:10.72.211.141:161

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Encoding

Encode video for uploading to Youtube/Vimeo. The output should be a similar quality as the input and will hopefully be a more manageable size.

ffmpeg -i input.avi -c:v libx264 -preset slow -crf 18 -c:a copy -pix_fmt yuv420p output.mkv

Same as above, but also re-encode the audio using AAC instead of stream copying it:

ffmpeg -i input.mov -c:v libx264 -preset slow -crf 18 -c:a aac -b:a 192k -pix_fmt yuv420p output.mkv

quyenlv

Create the RSA Key Pair

ssh-keygen -t rsa

Copy the public key to a server

ssh-copy-id user@server

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Installation

Install tacacs+ server:

sudo apt-get install tacacs+

Install tacacs+ client:

quyenlv

#!/usr/bin/perl

use strict;
use Getopt::Long qw(:config pass_through no_ignore_case bundling);

my $do_color;

GetOptions("colors"=>\$do_color);

my @buf;