Add image resizing and rotating to Gnome on Ubuntu

1. the package name is nautilus-image-converter, nautilus extension to mass resize or rotate images

sudo apt-get install nautilus-image-converter

2. logout and login again, or reboot, you will find right-click pop menu on image has the features we need

Set up a Tor relay node on Ubuntu

1. verify that your clock is set correctly

2. install tor

sudo apt-get install tor

3. make sure to define at least Nickname and the listening port, ORPort

sudo vi /etc/tor/torrc

--
.
.
SocksPort 9050 # what port to open for local application connections
SocksListenAddress 127.0.0.1 # accept connections only from localhost
.
Nickname ididnteditheconfig
.
RelayBandwidthRate 20 KBytes # Throttle traffic to 100KB/s (800Kbps)
RelayBandwidthBurst 40 KBytes # But allow bursts up to 200KB/s (1600Kbps)
.
ORPort 9001
.
.

5. restart tor to reload config

sudo /etc/init.d/tor restart

4. add this line to privoxy configuration file /etc/privoxy/config

forward-socks4a / localhost:9050 .

it means tor listens socks4a on port 9050
In the SOCKS 4A protocol, the DNS resolution of the target hostname happens on the SOCKS server, while in SOCKS 4 it happens locally.

5. according the default setting in /etc/privoxy/config

listen-address 127.0.0.1:8118

port 8118 should be used as http proxy

6. when your browser is set with privoxy proxy, you can check this website to verify

https://torcheck.xenobite.eu/


7. when you check log file, /var/log/tor/log
you may notice the warning message

MMM ddd hh:mm:ss.xxx [warn] Your application (using socks4 to port 80) is giving Tor only an IP address. Applications that do DNS resolves themselves may leak information. Consider using Socks4A (e.g. via privoxy or socat) instead. For more information, please see http://wiki.noreply.org/noreply/TheOnionRouter/TorFAQ#SOCKSAndDNS.


Set up CACTI on Ubuntu

1. install cacti, it depends on many packages like snmpd, apache2, mysql-server

sudo apt-get install cacti

2. installation in progress
password of your database's administrative user: password of mysql administrator
mysql application password for cacti: leave it blank, cacti will create a random password
webserver type: apache2

3. visit the webpage of your cacti server, http://localhost/cacti
follow cacti installation guide in your web-browse

4. login with default username and password, admin / admin

5. Devices -> Add
Description: Give this host a meaningful description.
Hostname: localhost
Host Template: Generic SNMP-enabled Host
SNMP Version: Version 1
SNMP Community: public
create

6. Associated Graph Templates -> Add Graph Template
add any you need

7. Associated Data Queries -> Add Data Query
add SNMP - Get Mounted Partitions and SNMP - Interface Statistics
save

8. Create Graphs for this Host
select any items you need
create

9. Graph Trees -> Add
Name: A useful name for this graph tree.
create

10 Tree Item -> Add
Tree Item Type: host
Tree Item Value -> Host: choose what you just created
create

Surface and Bad Blocks check of Hard Disk on Unix

1. unmount the device you want to check

umount /dev/sda1

2. search the device for bad blocks

# -s: show the progress of the scan
# -v: verbose mode

badblocks -sv /dev/sda1

--
create a filesystem that excludes the badblocks which have been checked

mke2fs -c /dev/sda1


Could not update ICEauthority file /home/user/.ICEauthority

this error makes me fail to login gnome

1. boot into recovery mode
press ESC while loading grub

2. chown user:user /home/user/.ICEauthority

3. chmod 644 /home/user/.ICEauthority

4. shutdown -r now
restart

Install command-line BitTorrent client, RTorrent on Ubuntu

rtorrent is a text-based ncurses BitTorrent client

1. install rtorrent

sudo apt-get install rtorrent

2. because ubuntu package of rtorrent doesn't include default configuration file, it would result in a warning messege, couldn't not read resource file: ~/.rtorrent.rc
we have to create the file

vi ~/.rtorrent.rc

--
# This is an example resource file for rTorrent. Copy to
# ~/.rtorrent.rc and enable/modify the options as needed. Remember to
# uncomment the options you wish to enable.

# Maximum and minimum number of peers to connect to per torrent.
#min_peers = 40
#max_peers = 100

# Same as above but for seeding completed torrents (-1 = same as downloading)
#min_peers_seed = 10
#max_peers_seed = 50

# Maximum number of simultanious uploads per torrent.
#max_uploads = 15

# Global upload and download rate in KiB. "0" for unlimited.
download_rate = 0
upload_rate = 180

# Default directory to save the downloaded torrents.
directory = ~/download

# Default session directory. Make sure you don't run multiple instance
# of rtorrent using the same session directory. Perhaps using a
# relative path?
session = ~/.rtorrent/session

# Watch a directory for new torrents, and stop those that have been
# deleted.
#schedule = watch_directory,5,5,load_start=./watch/*.torrent
#schedule = untied_directory,5,5,stop_untied=

# Close torrents when diskspace is low.
#schedule = low_diskspace,5,60,close_low_diskspace=100M

# Stop torrents when reaching upload ratio in percent,
# when also reaching total upload in bytes, or when
# reaching final upload ratio in percent.
# example: stop at ratio 2.0 with at least 200 MB uploaded, or else ratio 20.0
#schedule = ratio,60,60,"stop_on_ratio=200,200M,2000"

# The ip address reported to the tracker.
#ip = 127.0.0.1
#ip = rakshasa.no

# The ip address the listening socket and outgoing connections is
# bound to.
#bind = 127.0.0.1
#bind = rakshasa.no

# Port range to use for listening.
port_range = 6890-6999

# Start opening ports at a random position within the port range.
#port_random = no

# Check hash for finished torrents. Might be usefull until the bug is
# fixed that causes lack of diskspace not to be properly reported.
#check_hash = no

# Set whetever the client should try to connect to UDP trackers.
use_udp_trackers = yes

# Alternative calls to bind and ip that should handle dynamic ip's.
#schedule = ip_tick,0,1800,ip=rakshasa
#schedule = bind_tick,0,1800,bind=rakshasa

# Encryption options, set to none (default) or any combination of the following:
# allow_incoming, try_outgoing, require, require_RC4, enable_retry, prefer_plaintext
#
# The example value allows incoming encrypted connections, starts unencrypted
# outgoing connections but retries with encryption if they fail, preferring
# plaintext to RC4 encryption after the encrypted handshake
#
# encryption = allow_incoming,enable_retry,prefer_plaintext

# Enable DHT support for trackerless torrents or when all trackers are down.
# May be set to "disable" (completely disable DHT), "off" (do not start DHT),
# "auto" (start and stop DHT as needed), or "on" (start DHT immediately).
# The default is "off". For DHT to work, a session directory must be defined.
#
dht = on

# UDP port to use for DHT.
#
dht_port = 6881

# Enable peer exchange (for torrents not marked private)
#
peer_exchange = yes

scgi_port = localhost:5000
encoding_list = UTF-8

#
# Do not modify the following parameters unless you know what you're doing.
#

# Hash read-ahead controls how many MB to request the kernel to read
# ahead. If the value is too low the disk may not be fully utilized,
# while if too high the kernel might not be able to keep the read
# pages in memory thus end up trashing.
#hash_read_ahead = 10

# Interval between attempts to check the hash, in milliseconds.
#hash_interval = 100

# Number of attempts to check the hash while using the mincore status,
# before forcing. Overworked systems might need lower values to get a
# decent hash checking rate.
#hash_max_tries = 10

3. create directory structure for the need of rtorrent resource file we just made

mkdir -p .rtorrent/session

4. type rtorrent to run rtorrent
about rtorrent operation, check out http://libtorrent.rakshasa.no/wiki/RTorrentUserGuide

Change boot loader of Ultimate Boot CD to grub on a USB stick

1. use hp formatting tool to format usb flash drive as USB-HDD because the formatting function of window will make it as USB-ZIP

2. repeat step 1 ~ 3 in Change boot loader of Slax to grub on a USB stick if your usb stick is not bootable

3. download iso image of ubcd from http://www.ultimatebootcd.com/download.html and extract it

4. download converted grub menus then
delete syslinux, isolinux folders, menus folder and boot.catalog
copy grldr, grub.exe, memdisk, new downloaded menus folder and menu.lst to the iso root directory

5. rebuild the iso

mkisofs -R -b grldr -no-emul-boot -boot-load-size 4 -allow-lowercase -o ubcd411.iso d:\ubcd411


4. copy the new iso to the usb stick then edit menu.lst and add below

title Ultimate Boot CD
find --set-root /ubcd411.iso
map /ubcd411.iso (hd32)
map --hook
root (hd32)
chainloader (hd32)