2010-07-26

FreeBSD - How to allow normal user to mount USB drive

Recently, I've got a few external hard disk and one of them is formatted into file system FAT32 (msdosfs or vfat), because the files are to be interchange between Linux, OSX & FreeBSD. After the files are save from OSX, the external hard disk cannot be mounted onto FreeBSD or PC-BSD as a normal user. Since these are just some media files and frequently need to be interchange between these 2 OS, I'm quite reluctant to mount it using root or sudo. After all, root or sudo are suppose to be used for system administration.

On the FreeBSD box, some system value & devfs needed to be change in order for the external USB hard disk can be mounted. As for PC-BSD, the "hald" failed to mount the USB external hard disk because this USB external hard disk FAT32 partition is too big. Some changes needs to be done on "hald" but being a command line geek, I'd rather meddle these in command line. By the way, the error message pops out on the "Dolpine" (KDE) file manager is :
"An error occurred while accessing '160gb', the system responded:
org.freedesktop.Hal.Device.Volume.UnknownFailure: mount_msdosfs:
/dev/msdosfs/160gb: Disk too big, try '-o large' mount option : Invalid argument"

Again, "If doubt, refer de FreeBSD Handbook" shed light. These steps are to be executed as root or equivalent privilege. Also, the normal user that is intended to mount the external hard disk, need to be part of the group "wheel". Below are the steps that I've taken to allow normal user to mount a external USB drive :

2010-07-23

N900 - How to clear all the phone data & settings

N900 is a great phone with a lot of drooling features (refer to this post "N900 - A phone running open source OS & programs"). Particularly, because it is running Maemo which have a active & generous community. But I've to give it up because I've found a phone that fits more into my lifestyle. Nonetheless, it is still great mobile phone to have.

The N900 is different from other mobile phone. The usual way of resetting the phone from the phone settings menu will only clear the mobile phone settings, but the OS & data (eMMC) are still intact. Before selling off this phone to the next person, I've gotta clear all the stuff in it, especially the data.

Below are the steps on how to flush the phone & clears all the data and settings :

2010-07-21

Blackberry - How to reboot the phone using keyboard shortcut key

After an update of the blackberry OS or some software installation, it might prompt to reboot the blackberry phone in order to finish the installation. But some times, we need to use it so we'll choose "Reboot Later" but after finishing using it, how do we initiate the reboot sequence?

Once in a blue moon, the phone is acting up a bit weird, application not responding, some apps is taking too long to respond or the phone performance is lagging. A reboot might be a good try to ditch those weird acts.

This is how to reboot the phone using keyboard shortcut key :

2010-07-19

FreeBSD - How to compile custom kernel

Normally, the generic kernel that comes with default FreeBSD installations are good enough for most installations. But some machines that I worked on are having more then 4gb of memory. Be default, the i386 processor architecture only recognizes 4gb or less memory. Any random access memory larger then 4gb, the kernel will need to enable the feature PAE (Physical Address Extension) in order to make use of the processor's extended physical address space, from 32-bin to 36-bit. After compiling PAE kernel feature, the 4gb limit will increase to 64gb.

Most of the time, I re-compile the kernel because of the server hardware comes with more then 4gb of memory. But recently I'm setting up a firewall that need to do traffic shaping, through QoS (Quality of Service). PF's ALTQ feature will do the traffic shaping, but by default, it is not included in the default kernel.

This post will show how to compile custom kernel in FreeBSD so that it includes the ALTQ feature :

2010-07-17

FreeBSD - How to reset root account password

After the initial installation, the root password should be changed to a complicated enough password, then forget it. We're not suppose to use the root login & password as it might exposed to unnecessary risk. My preferred way of system administration should use sudo. It's more secure, controllable, and flexible.

But things happen. Today, I've totally forgotten root password. The box is lock out to the extend that only console access is allow. Worse of all, the regular password for the user name that I used to login for sysadmin stuff, have been "forgotten" as well too. Too Bad...

Anyway, as long as the physical box can be access, no security measures is good enough to stop the box being compromise. :P

This box is running the superior FreeBSD OS. The root password can be reset by :

2010-07-15

N900 - How to overclock the processor speed of N900

The N900 is a flexible mobile phone that runs Maemo operating system. It should not be compare as a mobile phone but rather as a mobile tablet with an extra function, phone. As my previous post introduction, it comes with a large display, keyboard & a snappy processor. Because of Maemo, now it even allows processor overclocking.

By overclocking to 850mhz, I've noticed that the average battery usage life have increase up to 30%. From an average of 3 days per charge to less then 5 days per charge. And of cause, because the processor is running faster then the default 600mhz, it boosts the response of application execution. To anyone that is interested in overclocking this phone, this post will show how to overclock the N900 to 850mhz which I find this speed is a balanced between speed & battery life. Anything higher then this might spoil the phone. You've been warned.

Here's how to overclock the processor of N900 :

2010-07-14

BlackBerry - Multi alarm clock application on BlackBerry

Like most of the mobile users, I use my blackberry phone as an alarm clock. But the alarm clock application that comes with it only allow to have one alarm entry at a time. Which is not enough for my lifestyle.

I did thought of using the calendar reminder as alarm clock but that would disrupt my daily todo stuff & meeting reminder ringtone. Multiple alarm clock entry is a simple and yet important function, how can RIM (Research In Motion) forget it?

After some meddling with the phone, I concluded RIM did not overlook this function. But rather, it "hides" it in a app that I've all the while never think of.

This is how to set multiple entry alarm clock on a blackberry phone :

2010-07-13

BlackBerry - Quite a smart phone

BlackBerry is a smartphone that aims not only business user, but also casual user that wanna connect to people. The rich social application that comes with BlackBerry encourages frequent communication between people, through various channels. e.g. :
  • BBM (BlackBerry Messenger) is another kind of messenger that is capable of transmitting picture, sound, file or even GPS location to contact list.
  • twitter client
  • push email (with gmail, is more addictive then sms)
  • GPS map with integration into the above mentioned services

Since BlackBerry is a Smart Phone, it has the usual PIM (Personal information management) applications. e.g.

2010-07-11

OSX - How to retrieve files on external hdd with HFS+ file system

HFS+ => Hierarchical File System Plus

Apple's OS X uses HFS+ (HFS plus) file system. It is the default file system since OS X Tiger (10.4). 255 characters can be used in file name. It can support up to 8 million terabytes and yes, that's huge!

I've just got a external hard disk and decided to format it using HFS+ file system as it is more efficient when mounted on the mac, which I used it most of my time. One concern though, should the mac die suddenly, how can I retrieve the files while getting a new mac?

Here's how to retrieve the files on the external hard disk on Linux?

2010-07-05

OS X - Screen appear blur and only center part seems clear

One fine day, when I turn on my mac, suddenly everything on the display seems blur. Only the center part of the screen display is clear & sharp (like normal). It almost seems like it is a display card problem. But reluctant to make this an excuse to change my mac (:p), I check out the system preferences. And I noticed that there's a zoom function at "Universal Access". Just trying my luck to turn off using "apple key + alt + 8", the display looks fine again!



Playing around with it and the below is what found out :