Windows Server 2008 PDC external time

Internet time is hidden from control panel.
As a PDC, Windows Server 2008 need to be synchronized with external source.
You can select the closest NTP server from http://www.pool.ntp.org/en/

Microsoft recommends (quote from technet.microsoft.com):

  1. Click Start, and then click Command Prompt.
  2. In the Command Prompt window, type the following line, where peers is a comma-separated list of IP addresses of the appropriate time sources, and press ENTER:w32tm /config /manualpeerlist: peers /syncfromflags:MANUALThe time sources you choose depend on your time zone. For example, if your domain controller is located in the Pacific Time zone, this line might read:w32tm /config /manualpeerlist:131.107.1.10 /syncfromflags:MANUALIn this example, the IP address of the timeserver is used instead of the fully qualified domain name for security purposes.
  3. Press ENTER. You should get a message that the command completed successfully.
  4. Type w32tm /config /update
  5. Press ENTER. You should get a message that the command completed successfully.W32time uses a variable poll interval based on the quality of timesync with the server. On DCs, this interval defaults to between 64 and 1024 seconds.
  6. To immediately synchronize with the external time server, type w32tm /resync and press ENTER. You should get a message that the command completed successfully.
  1. Type Exit and press ENTER.

Example:
For Canada we can use
ca.pool.ntp.org wich has the ip 207.194.97.58 or
clyde.concordia.ca 132.205.1.1
bonnie.concordia.ca 132.205.7.81
tick.encs.concordia.ca 132.205.96.93
tock.encs.concordia.ca 132.205.96.94

w32tm /config /manualpeerlist:207.194.97.58 /syncfromflags:MANUAL
w32tm /config /syncfromflags:manual /manualpeerlist:”132.205.96.94,0×1 207.194.97.58,0×1 ” /update /reliable:yes

Blocking spambots with SCROLLOUT F1 and fail2ban

I asume that you have a fuly functional SCROLLOUT F1 instalation and you want to add spambot blocking feature.
Ad the following line to /etc/apt/sources list

deb http://ftp.debian.org/debian unstable main

Then run

apt-get update
apt-get -t unstable install fail2ban
cd /etc/fail2ban
cp jail.conf jail.local

Edit jail.local

[postfix]
enabled = true
port = smtp,ssmtp
filter = postfix
logpath = /var/log/mail.log
maxretry = 2
bantime = 7200

Edit /etc/fail2ban/filter.d/postfix.conf

failregex = reject: RCPT from (.*)\[\]: 450 4.7.1
reject: RCPT from (.*)\[\]: 554 5.7.1
reject: RCPT from (.*)\[\]: 550 5.1.1
reject: RCPT from (.*)\[\]:\d{5}: 550 5.5.1

Then run
service fail2ban restart
To check if it is working run:

fail2ban-client status postfix
iptables -L -n

You can play with following parameters:
maxretry, bantime, findtime
Do not forget:

  • always edit jail.local instead of jail.conf (this way you don not risk to stay outside if software is updated
  • put your trusted IP addresses in ignoreip

Low budget High Quality Digital Stereo Sound for Mac OS X Lion

Introduction:

I used to have a 5.1 THX certified Logitech 5300Z sound system. Sound great, but some inconveniences related to analog 5.1 audio systems: extra wiring for rear speakers, only one audio source, huge subwoofer, lack of digital connectivity. I sold it with intention to buy Logitech Z-5500 that has digital inputs. Besides the fact that the last has digital input, still the same disadvantages and a huge price. Because I am not a gamer, I realized that a Studio Monitor Speaker (http://en.wikipedia.org/wiki/Studio_monitor) will provide a sound quality without compromise at the lowest possible price. Those are the smallest speakers used by professionals and in the same time has enough juice for an apartment room. M-Audio Compact Monitor Speakers (AV30) it is the extreme low cost solution as analog Studio Monitor. I finally chose MA-15D by Roland for following reasons: 2 input mixers, 1 digital input (SPDIF coaxial &  optical) and 1 analog input (2x RCA + 1x 3.5mm jack).

Goals:

  • Low Cost High Fidelity stereo audiophile digital system without quality compromise
  • SPDIF output sound card
  • SPDIF input speakers
  • Multiple input sources
IMPORTANT NOTE: Use the following informations on your own risk. I try to describe my personal experience the best as I can, however the results are not guaranteed and I am not responsible for any hardware or software  damage or loss of money or productivity.

Current Hardware:

  • MA-15D CakeWalk By Roland Digital Monitor Speakers
  • Realtek ALC8xx compatible sound card (P55A-UD3 Motherboard)

Alternative Hardware:

  • any digital sound system that accept SPDIF stereo input (! not Surround)
  • any sound-card that use AppleHDA natively (not voodoohda, if possible)

Current Software:

  • Mac OS Lion 10.7.3
  • Realtek  ALC8xx driver from MultiBeast 4.5.1
  • Sound Flower (http://code.google.com/p/soundflower/downloads/list)

MA-15D: Digital Stereo Micro Monitors (Manufacturer description follows)

The MA-15D stereo reference monitors are ideal for computer-based recording artists seeking a high-quality, powerful set of reference speakers to use in a relatively confined space. The MA-15Ds offer a wide-range spectrum and crystal-clear audio reproduction.
Bass Enhancer
24-bit/192kHz support, S/PDIF optical & coaxial input
Subwoofer output port for bass boost
15 watts per channel
3 independent source inputs: 1/8" line, RCA pin line (L/R), and S/PDIF (optical & coaxial)
Front-controlled bass, treble, and 2 independent volume controls
100 mm (4") woofer + 50 mm (2") tweeter, 2 way bass-reflex enclosure
1/4" headphones port
Magnetically shielded

 

Actual  wiring:

wiring diagram

As you can see in the picture I use  1/8″  Line 1 for ipod, when I need to listen music in silence, P55A-UD3 Motherboard connected via optical/coaxial cable (check selector switch), audio out from Videotron Explorer 3200 via standard RCA audio cable.

For analog connections there is nothing to do. As per specifications MA-15D speakers accept theoretically 24-bit/192kHz digital input. This is possible in Windows 7. In Mac OS X Lion, on SPDIF output the following combinations work with MA-15D:

24-bit/44.1kHz
24-bit/48kHz
24-bit/88.2kHz
24-bit/96kHz

If you have Apple Keyboard with F10, F11, F12 keys mapped for volume control, there are useless if you select SPDIF output. However you can adjust the volume individually per application. The major problem here is that Preview application volume is based on master system volume.

The best work around  to fix master volume and keyboard shortcuts (F10, F11, F12) with SPDIF output is to route applications output through Soundflower than to SPDIF.

Let’s proceed next with.

Software settings:

If you have Apple computer, skip this step. If you have like me a Realtek HDA8xx based sound card use MultiBeast in order to install the proper driver.

IMPORTANT NOTE: Use the following advices on your own risk.
Always do appropriate back-up before any major software changes and make sure you know how to put everything back.

In System/Library/Extensions remove AppleHDA.kext and all kexts that reffer a HDA device. Also remove any voodoohda kexts. Make sure not to remove other kexts than audio driver related.

Run MultiBeast and install ALC8xxHDA driver.

 

Download Sound Flower from http://code.google.com/p/soundflower/downloads/list and install the package.

In System Preferences > Sound, setup default output device as Soundflower (2ch)

In Soundflower setting set the output as Built-in Digital output.

In Applications>Utilities>Audio Midi Setup, set the 24-bit integer/48000Hz sample rate  for Built-in Digital output (SPDIF) and 48000Hz for Soundflower

This way the sound routing should be like this:

Application > Soundflower > SPDIF output

Now the master volume and volume keyboard shortcuts should work fine.

Known issues: if mute or no sound for a long time, Soundflower enter in a kind of saving power mode, just click on any output and again on Digital Output and everything is working again. If you have a solution for this, please leave a comment with solution.

How to recover ext4 from GPT partitioned disk

Hard drive sizes had increased dramatically in last several years, but block device drivers are still outdated. For hard drives more than 1TB currently seems to be an advantage to use GPT instead of legacy MBR partition table. You can see more details at http://en.wikipedia.org/wiki/GUID_Partition_Table .

One of the inevitable disadvantage of GPT is the possibility of corruption by using outdated partition editor like cfdisk, or other disk tools, even without any intention to modify the partition.

It happened recently on one 1.5TB WD Caviar Green with GPT and one ext4 partition full of data.

I tried to repair the superblock using tools like:

  • For partition listing:

fdisk -l

  • To check the filesystem:

fsck.ext4 -v /dev/xxx

  • To list where the superblock backups are stored:

mke2fs -n /dev/xxx

  • To restore superblock from backup:

e2fsck -b block_number /dev/xxx

My story was completly different. It does not work this time. Could work fine if you have a traditional MBR partition table. In case of GPT, TestDisk was the magic software that saved my disk. Read documentation first, think carefully what do you want to do and you have a chance to recover 100% your disk. One note here. TestDisk has an “invasive mode” and a “recovery mode”. In recovery mode you can save a specific file or a disk image. This is not distructive. But you must have a spare disk to save the data. In my case I simply fixed the GPT table and I was lucky. That is why I recommend you to fully read the documentation from TestDisk.

http://www.cgsecurity.org/wiki/TestDisk

 

Clear DNS cache windows

Operating systems affected: MicrosoftTM Windows XP, Windows Vista, Windows 7

To clear dns cache:
ipconfig /flushdns

To restart dnscache service:
net stop dnscache
net start dnscache

You can also do this visually from MMC. Just type services.msc in run/search and use appropriate command in order to restart dnscache service.

Benefits: could solve web browsing problems if internet connection is ok with many websites but not with all.
Also it is good to see if you recently moved your hosting and you have changed the name-servers.
This apply just for desktop computer you use to browse when everybody see a website but not you. For DNS servers, it is another story.

Also it is possible to clean DNS cache per browser like Firefox, etc. like you can see on other articles on this website.

Wipe free space on Mac with CCleaner

The well known Piriform’s  PC Optimization software CCleaner it is now available on Mac for Leopard, Snow Leopard and Lion. It this post I will show You how to use “Wipe Free Space” feature of CCleaner.

But why should I wipe the free space on a hard disk?

When you create any sort of file in your system, what happens here is that there is actually a certain  hard drive space that is assigned to that file. That memory space is unique to that particular file. Now, when you delete that file, it would then be transferred to the Trash. When you empty your Trash, you then get rid of the file effectively, right? Wrong.

The hard drive space that was once assigned to the deleted file remains in existence. As long as this still exists,  can be virtually recovered by skilled technicians or hackers. This is one of the principles of data recovery software. So if You want that an information sent to Trash to be effectively removed forever, you need to use a wipe free space software.

wipe free space

wipe free space

CCleaner it is able currently to do 3 types of wiping: Zero Out, 7-pass erase and 35-pass erase. Any of those methods will generally make impossible recovery using commercial grade software recovery. The number of erasing passes it is relevant just for very sensitive data that could be hardware recovered by specialized laboratories in an controlled environment using direct plate reading even from defective hard drivers. But in this case it is better to use dedicated erasing software that include DoD and other sophisticated algorithms.

From http://www.piriform.com/ccleaner you can download CCleaner for Mac.

You can install like any usual application, with a simple drag to application folder.

In the tools tab You will find the Erase Free Space button as you can see in this screenshot.

wiped free space

wipe free space

You can choose the hard drive volume of which you want to wipe the free space. After that you simply press the Erase Free Space button. Depends on the size of the disk, could run for few minutes or for hours.

Free Online Photo and Image Editor – IMAGEBOT

www.tipit.infoWe are often use online editors, like webmail as an email editor, Google Docs as Office suite replacement for simple Word and Excel documents. Even photo manipulation web tools are popular. Recently I found out that the first free vector art library OpenClipart is using a online web editor to edit their .svg files. Even was ignored by major vendors like Adobe and Corel, .svg format is popular to InkScape users.

This logo was generated using imagebot editor from http://www.flamingtext.com  http://www.flamingtext.com/imagebot/editor

The tool is pretty simple to use. You can easily and fast create banners or buttons. You can work with layers, basic shapes and some effects. You can also save the work as png, pdf, svg, or jpg.

I will recommend for web use or for print just for small formats. That is because the effects are rasterized as bitmap no matter if you save as pdf or svg. So it is not a true vector editor, but very useful for quick projects.

ImagebotImagebot

Quick print high resolution coloring page using Illustrator

You have a Mac, Illustrator and some kids. You need to print quickly few coloring pages for them. The only problem is that most of images are low res. With newest versions of Illustrator  we can easily convert any bitmap image in a vector image, using Live  Trace

3 easy steps:

  1. Search in Google Images the word “coloring” and image type “Line drawing”
  2. Download the image that you wish to print. Usually the coloring websites allow to use the image for personal printing purposes.
  3. Create a new letter CMYK document in Illustrator.
  4. Place the image in Illustrator
  5. Click on image. On a top you will see Live Trace button
  6. And now, the secret, for Line drawing images, with Inked Drawing Live Trace preset You can have one of the best results. So use the drop down of Live Trace Tool and select Inked Drawing preset.
  7. All done. You can now print on letter paper with your home printer.

You have also the screenshots:

Speed up file tranfer between MAC OS X and Linux Samba Server

After scratching my head few weeks, tweaking a lot smb.conf on my linux box, I found a Finder workaround, based on turning off display of server in sidebar.

Symptom: Slow file transfer over the network, between a MAC OS X Lion machine and a Linux machine (archlinux, currnet version). Also slow transfer between MAC and a PC based file server. How slow, let say finder reports about 1 hour for a CD size .iso file.

How to do it:

  1. Open Finder Preferences
  2. On Sidebar tab, disable Connected Servers
  3. On General tab, check Connected Servers

As a result, the mounted volume will appear on the desktop instead of sidebar.

In my case, this Finder workaround helped me to increase the speed more than 20x.

Please let me know if this has improved the share browsing and the file transfer speed in your case.Thanks.