Sticky tape for my memory

Preventing iTunes to automatically backup your iDevice

2012-01-08T12:13:00.000+01:00

I don't know about you, but I get very annoyed when I have to wait for iTunes to finish the backup of my iPhone or iPad. There is no option in iTunes to disable automatic backup.
Follow along this post explain how to accomplish that.

Quit iTunes
Open Terminal
Type or copy and paste the line below

defaults write com.apple.iTunes AutomaticDeviceBackupsDisabled -bool true

That prevent backup to happen, but allows you to manually do it at your own will 'ctrl clicking' the device icon, like in the picture

To revert the original backup behavior

defaults write com.apple.iTunes AutomaticDeviceBackupsDisabled -bool false

or completely get rid of the key AutomaticDeviceBackupsDisabled added with defaults write

defaults delete com.apple.iTunes AutomaticDeviceBackupsDisabled

What about if you don't even want to be able to perform a manual backup?

defaults write com.apple.iTunes DeviceBackupsDisabled -bool true

To revert the original backup behavior

defaults write com.apple.iTunes DeviceBackupsDisabled -bool false

or completely get rid of the key DeviceBackupsDisabled added with defaults write

defaults delete com.apple.iTunes DeviceBackupsDisabled

Footnote
I tested this hack on a Macintosh with iTunes 10.5.2 and worked as expected with iPhone 4, iPad and iPad2.

Enable FTP service in OS X Lion

2011-11-04T02:33:00.000+01:00

OS X Lion does not have anymore the option in System Preferences, to activate the FTP server.
Fortunately the daemon is there, just dormant.

To wake it up launch Terminal and type

sudo -s launchctl load -w /System/Library/LaunchDaemons/ftp.plist

You can disable FTP anytime typing the following command

sudo -s launchctl unload -w /System/Library/LaunchDaemons/ftp.plist

Enable Administrator in Windows 7

2011-06-01T21:57:00.000+02:00

To enable the Administrator account in Windows 7, the quickest way is running a Command Prompt session with Run as administrator

At the prompt type

net user administrator /active:yes

At this point it is recommended to assign a good password.

To disable the Administrator account

net user administrator /active:no

Cables. Who cares?

2011-01-21T23:25:00.002+01:00

A few days ago I was struggling with a desktop multifunction Samsung printer.

Everything was fine except, the scanner.

The MFP was hooked up to a PC with a USB cable.
Whenever I tried to scan a document, an error panel appeard saying Hardware I/0 error.
I removed and downloaded the latest drivers from Samsung support site without luck.

Changing the USB cable with a new, good shielded, not too long one, removed the impediment.

PowerMac G5 DP using one processor

2011-01-21T23:00:00.000+01:00

Suddenly a PowerMac G5 Dual Processor started having kernel panic after a few minutes from start up.

It turned out that one of the two processors was faulty.

A Google search reported that in a DP PowerMac, if the first processor is damaged, usually the computer does not even boot up.

While, if it is the second, it shows the behavior I experienced.

I was able to circumvent the problem leaving the processor in its place.

To do so, you must enter Open Firmware.
Immediately after the startup sound, press and hold the key combination Command-Option-O-F
Release the keys when you see a white screen that says "Welcome to Open Firmware."

At the prompt type

setenv boot-args cpus=1

and hit return. If the syntax was correct you got an OK result.
Now type

mac-boot

hit return and the operating system boots.
I tested the reliability of the new mono PowerMac :-) by running Grapher, find the program inside Utilities folder, with a few windows drawing 3D animations for more than two hours and no crash at all.

Beware! Reissue the Open Firmware procedure if you reset PRAM

Backup strategy with rsync

2010-03-11T10:09:00.004+01:00

Everyone knows backups are important.
But usually everybody doesn't care much about them until an unrecoverable event happens.
So, why wait for that very moment, if, with a little bit of effort, you can have a rock solid data backup strategy.

A very good review on how to use the standard *nix rsync program to backup your valued electronic data.

Easy Automated Snapshot-Style Backups with Linux and Rsync

Mac OS X print presets

2010-03-10T14:02:00.000+01:00

Let's say you have a color laser printer installed in your system but you usually print in black and white.
It is very likely that the printer presets are in color.
So, every time you need to print a document, and you need it B/W, you have to go through the printer settings and choose the appropriate parameters.
That could eventually become annoying.
Yes, it is possible to create one or more personalized presets to choose from, before hitting the Print button, but that is not always the perfect solution.
There are programs, i.e. the MS Office suite, that have a nice little button with a printer, which sends the document directly to the print queue, bypassing the print dialogue screen.

If you want to modify the "Standard" presets there is a straightforward solution. Just fire up your browser and fill the URL bar with the address below or just click the link

http://localhost:631

It'll be presented the CUPS (Common UNIX Printing System) page. From there, you can change whatever you want regarding the printer or printers settings that will became the new defaults.

VNC screen scrambled

2009-05-16T15:21:00.000+02:00

Many Apple servers out there are headless. That is particularly true for the ones before the advent of the Xserve with Intel processor.
And quite often, servers are managed remotely using software like the multitude of VNC server (GPL) or Apple Remote Desktop (commercial).

I personally choose Vine Server OSX Vnc to control a couple of Xserve. One with Panther server and the other one with Tiger server. This program has the advantage to handle international keyboard layout over the VNC server self contained in Tiger which can't.

I think I played around with Monitor Preferences because at some point logging into the VNC server presented a screen like this.

For some times I ended up quitting the VNC client and relaunching it again to get a comprehensible image. But that was very annoying.

So I did some internet searches and I found the solution to the problem removing the file
/Library/Preferences/com.apple.windowserver.plist
on the server side.

NT Backup and .bks file (reloaded)

2009-05-03T13:03:00.001+02:00

The Windows program NT Backup can use a file with the extension .bks that contains the list of files or group of files to be saved.
As a matter of fact you can also use this file to exclude some files you don't want to be included into the backup set.

The syntax of the .bks file is as follows

X:\
This entire drive will be backed up.
X:\Folder_name\
Files in this folder will be backed up.
X:\Folder_name\ /exclude
Files in this folder will be excluded.
X:\File_name.ext
This file will be backed up.
X:\File_name.ext /exclude
This file will be excluded.
SystemState
The System State will be backed up.
\\Server\Share\Folder\
These network files will be backed up.

This file is normally created and managed by the program itself and it seems to be the only way to obtain a properly formatted .bks.

In fact, the .bks file is a "special" UNICODE file without the Unicode header (0xFFFE).
If you manually edit this file i.e. with NOTEPAD, the standard text editor included since the first version of Windows, and save it as a Unicode you are ruined. The scheduled backup job stop working.
It is very handy indeed to be able to manage that file as you like with your favourite text editor.
As long as you do that you need to strip the first two bytes (0xFFFE) off the .bks.

A simple way is to use a hexadecimal file editor.

Below you'll find some links to a few Hex Editor programs

Windows
Hex Editor XVI32

Mac OS X
HexEdit

Linux
Midnight Commander

Ubuntu, how to regenerate OpenSSH host keys

2009-01-24T21:38:00.001+01:00

First, change directory to /etc/ssh

cd /etc/ssh

now, remove the old rsa and dsa keys files

sudo rm ssh_host_*

Generate new keys

sudo dpkg-reconfigure openssh-server

If you wanto to be 100% sure that the server you are connecting to is the one it claims to be, take note of the RSA and DSA fingerprint

sudo ssh-keygen -l -f ssh_host_rsa_key
sudo ssh-keygen -l -f ssh_host_dsa_key

to check against the fingerprint displayed next time you are going to connect.

Last, update your known_hosts file

~/.ssh/known_hosts

removing the line that contains the old reference, otherwise you'll get the following message

@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
@ WARNING: REMOTE HOST IDENTIFICATION HAS CHANGED! @
@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
IT IS POSSIBLE THAT SOMEONE IS DOING SOMETHING NASTY!
Someone could be eavesdropping on you right now (man-in-the-middle attack)!

Stop VMware Fusion to automatically map shared folders

2009-01-16T18:45:00.000+01:00

If your Windows XP virtual machine under VMware Fusion (v2) insist to map the shared folder as unit Z: and creates a shortcut on the desktop you must edit the relative .vmx file.

Usually this file is hidden under the following directory

/Users/YourUserName/Documents/Virtual Machines/YourWinVMName.vmwarevm

Find and change to FALSE the following keys

hgfs.mapRootShare = "TRUE"
hgfs.linkRootShare = "TRUE"

The first one is in charge to map the share without your intervention, so that when you open up My Computer you magically find a Z: unit.
The last one tells Fusion to create a shortcut on the desktop.

Mutt and nbSMTP

2008-12-27T00:22:00.002+01:00

Not so long ago I installed in different locations a few PCs as servers.
I choose Ubuntu server edition 8.0.4 LTS (Long-Term Support) aka Hardy Heron, the latest LTS version available from Canonical.
I prefer the hard way, without the GUI. Sorry, I don't like Linux GUIs ;-)
That way I can control what is installed, and install just what is really useful for that particular machine, leaving precious resources to services that need them. There is also another advantage. Limiting possible security issues.
One of these servers, in particular, has to manage the nightly backup of another server, this time a Windows 2003, via rsync.
I created a bash script to do the job and scheduled it with crontab.
The script, during the process, creates a report that is saved as a zip archive when the work is finished.
I was wondering how could I get that file to check everything was fine, without remotely access the server.
The obvious response was. By e-mail.
I started hunting for information in search for the most elegant solution with the minimum impact on the system.

What I found, and I picked, to achieve my goal, are these two little gems.

Mutt "a small but very powerful text-based mail client for Unix operating systems" and No Brainer SMTP nbSMTP "a simple MTA to send your mails to another mail server via SMTP".

First step. Retrieve and install the two packages. In Ubunto the apt-get command is aimed at that.

sudo apt-get install mutt
sudo apt-get install nbsmtp

I created a user specific .muttrc containing these lines

# No need to keep copy of the outgoing messages
set copy=no
# Some changes to the message headers
set hdrs=yes
my_hdr From: Me the sender <me@mydomain.com>
# How to invoke nbsmtp
set sendmail="/usr/bin/nbsmtp -f me@mydomain.com -d mydomain.com -h my_isp_smtp_server.com"

and to complete the work, at the end of the bash script that is supposed to make the backup, I've added the line in charge of sending the message

mutt -s "Backup report" -a report.zip me@mydomain.com < messagebody.txt

"Backup report" - is the subject of the message (option -s)
report.zip - is the attachment (option -a)
me@mydomain.com - is the recipient
messagebody.txt - is the main body of the e-mail (read message from the file messagebody.txt)

The file messagebody.txt could be anything you want to insert as the body of the message being sent.

Last but not least :-) I've also inserted this line into crontab file

MAILTO=""

to avoid error warning in log file
nbSMTP does not support the -o arguments from sendmail, ignoring them

because every time a croned job is executed mail is sent to the owner of the crontab

Windows XP Display Properties

2008-09-21T12:39:00.000+02:00

Generally due to a virus attack, sometimes some pages under Display Properties are no longer available.
Run Regedit and search for
HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Policies\System\

Remove keys, if they are present

NoDispAppearancePage
NoDispBackgroundPage
NoDispScrSavPage
NoDispSettingsPage

Now the Display Properties should be OK.

If, also the Task Manager is grayed out, there is a chance to find this key too

DisableTaskMgr

that must be removed.

How to change default umask Leopard, Tiger and Panther

2008-07-19T11:53:00.000+02:00

If, for some reason, you need to change the default umask (022) in Mac OS X Leopard the following article helps you in achieving that goal.

The article refers to Leopard server.
I tried it on Leopard workstation and seems to work just fine too.

The same can be done for Mac OS X Tiger in Terminal

sudo defaults write -g NSUmask -int value

as stated in Command Line 10.4 2nd edition manual

The above example applies on Mac OS X Panther too.

*** BE CAREFUL ***
These changes could possibly have nasty consequences on the normal behaviour of the system.

I don't want IPv6 in Ubuntu

2008-01-17T23:41:00.000+01:00

By default all major distributions of Linux nowadays are IPv6 enabled.
That is true also for Ubuntu server v6.06.1 aka Dapper Drake.

Sometimes leaving IPv6 enabled can cause little annoyances.

Fire up your favourite text editor and sudo edit this file

/etc/modprobe.d/aliases

Replace the line alias net-pf-10 ipv6 with alias net-pf-10 off.

Restart the computer and check the result with this line

ip a | grep inet6

If nothing appears IPv6 has gone :-)

Read here the original article

Mac OS X (Tiger) and VPN

2007-12-27T12:04:00.000+01:00

This article applies to the latest update of Mac OS X Tiger, 10.4.11. I cannot tell, if you can find the option described here, in a previous version of the operating system.

In Mac OS X you can create VPN client connections by the application Internet Connect, under the Application folder.

The procedure is straightforward, but at the end there is only one annoying issue.
When you decide to start up your new VPN connection to connect to the remote LAN it is impossible to use your gateway to continue to surf the web or download e-mails until you close the VPN.
In the best scenario you end up using the gateway of the remote LAN in the worst one you are limited to access only machines and devices of the remote LAN.

The solution is not too far. Select the menu "Connect" and then Option from the Internet Connect app.
Uncheck "Send all traffic over vpn connection" and confirm your choice.
This is a global option, that applies to every VPN connection you may have in your list.

Mac OS X and the file hosts

2007-12-11T18:45:00.000+01:00

Mac OS X stores the file hosts in /private/etc directory.
hosts is useful when there is no DNS server on the LAN and you want to reference a computer by name instead of its IP address.
In the majority of the Unix systems and Windows as well, editing the hosts file is sufficient to achieve the goal.
In Mac OS X it is also necessary to make changes at the local NetInfo database.

Here's how.

Mac OS X: How to Add Hosts to Local hosts File

Starting Mac OS X in safe mode

2007-10-17T17:43:00.000+02:00

Booting up Mac OS X in safe mode can solve some troubleshooting issues.

Beginning with Mac OS X version 10.2 and later it is possible to start the operating system in a special mode called "Safe Boot".
To do so you must press the shift key, just after switching on your Mac and holding it down until you see the spinning gear under the gray apple.

Find out what maintenance procedures are run, reading this Apple knowledge base article.

Windows XP desktop disappeared

2007-10-03T07:02:00.000+02:00

What if one day you turn on your PC and instead of displaying the desktop full of icons you'll just see the wallpaper.
And worse, even rebooting in safe mode has the same result.

Before preparing to reinstall the operating system you can try this.

Bring up task manager pressing Ctrl-Alt-Del. Choose "New task" from the File menu.
Type regedit in the run box and search for the following registry key.

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Image File Execution.options

There should be two subkeys. One named explorer.exe and the other iexplore.exe.
Delete both keys, close the Registry editor and restart the computer.

Resource Fork, how to get rid of it

2007-09-17T10:45:00.000+02:00

***** WARNING *****

Use the informations of this post at your own risk
You can loose data if you don't know what you are doing

How do you know if one file has associated resource fork with it.

It's fairly simple.
Open up the Terminal application. Change the directory to the one the file is located and type this command

ls -la filename/rsrc

If the file "filename" has resource you'll see an output like this one

-rw-r--r-- 1 yourusername yourusername 57847 Jan 1 2004 filename/rsrc

In this case the resource fork size is 57847 bytes long.

If the file has no resource fork at all, the file size should be 0 (zero).

What about get rid of this resource information

Create an empty file

touch emptyf

and copy it over the resource

cp emptyf filename/rsrc

Check the result issuing the ls command again

ls -la filename/rsrc

This time the output should look like this

-rw-r--r-- 1 yourusername yourusername 0 Sep 17 10:48 filename/rsrc

To know more about the macintosh file system read these articles

Apple

Wikipedia

Getting the username password logon panel

2007-05-17T23:41:00.000+02:00

In system preferences under account, login option, there are three choices regarding the way Mac OS X displays the logon panel to the user at the end of the startup process.

- Automatic logon as
- Users list
- Name and password

Generally the User list is the preferred picking because of the picture.
There are a sequence of keys that can momentarily change this behaviour from User list to Name and password.

Press the 'esc' key. The password box disappears.

Press the first letter of a user name in the list. The foreground around the picture and the name become darker.

Press alt(option)+shift+enter(return)

and in a matter of a second the panel changes its appearance, asking you to type in the user name and your password.

Can't install Mac OS onto your Macintosh?

2007-04-29T14:51:00.001+02:00

Every Macintosh computer comes with its own version of the operating system out of the box.

Some people, for any reason, want to have different versions of the Mac OS on the same computer.

This is possible only if you install a later version of the OS.

For example. Your Mac came with Mac OS X (Panther) 10.3.7.
Well, on that Mac you can neither install Mac OS X 10.3.6 nor any previous versions.
But, you can install any version of Mac OS X that came out after 10.3.7 without any trouble.

See this technical document for reference.

Diacritical mark on Italian Mac keyboard layout

2007-04-09T18:17:00.001+02:00

Every keyboard layout contains just a bunch of letters pertaining to the corresponding alphabet that a particular keyboard was made for.

For example, on the Macintosh Italian keyboard there are the most used accented letters in Italian words such as à, è, é, ì, ò, ù.
But from time to time it is necessary to use some other letters such as the Germanic ü.
Without switching the keyboard layout in System Preferences panel, is easy to obtain those letters, using dead keys.

A dead key produces no output when it is pressed, but modifies the output of the next key pressed after it.

Here you can see how is simple to get the most used character in Western country alphabets.

The option key is the key labelled with "alt". These key combinations are intended for Italian keyboard only.

´ option-8 (á, é, í, ó, ú)
` option-9 (à, è, ì, ò, ù)
¨ option-u (ä, ë, ï, ö, ü, ÿ)
^ option-^ (â, ê, î, ô, û)
~ option-n (ã, õ, ñ)

which is then followed by the letter the accent is intended for.
To obtain ñ press option plus the n key, release them, then press the n key again. In Mac OS X, pressing one of these key combinations creates the accent and hi-lights it, then produces the finalized character when a supported character is pressed, otherwise it leaves the accent remaining.

See Wikipedia for an exhaustive explanation.

Error authenticating Tiger clients against SMB server

2007-04-08T19:07:00.000+02:00

After upgrading a PowerMac from Mac OS X Jaguar to Mac OS X Tiger, this client couldn't access a remote folder hosted on a Sun server running Samba services.

I did not have access at the Sun server so I needed a solution for the client and fortunately I found it browsing the web.

The problem is that the Sun server expected the password from the client in clear text.

The following is a link to Apple knowledge base about this issue.