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Nine Dragon

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Written by cuongk6t

03/07/2012 at 9:07 am

Posted in Uncategorized

How to install D-COM 3G on CentOS 6.2 x86_64

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My Device: Huawei, model: E1550, HSDPA USB Stick.

Step 1: Plug in device to your PC, open terminal console.

Step 2: Check CentOS auto detect device as GSM modem by command:


In the Result of dmesg command, you must see some following line:

GSM modem converter now attached to ttyUSB0

GSM modem converter detected

GSM modem converter now attached to ttyUSB1

usbcore: registered new driver option

Step 3: Install wvdial (w v d i a l ) – it’s require libwvstreams on dependency

#yum install wvdial

Step 4: Build configuration file for wvdial and save it to /etc/

#wvdialconf  /etc/wvdial.conf

Check the result message to make sure it success: “Found a modem on /dev/ttyUSB0 (or 1)” and “Modem configuration written to /etc/wvdial.conf”

Step 5: Edit wvdial.conf file:

#vi  /etc/wvdial.conf

Press I to edit this file, uncomment 3 line: Phone, Username, Password by remove “;” begin of lines.

Add a new line after Init command (Init1, Init2…). If you have 2 Init, you must add Init3 in new line (if you have init3 already, you must add Init4….)

Init3 = AT+CGDCONT=1,”IP”,”e-connect

P/s: e-connect is the APN name of your mobile provider, in this case, I use D-COM sim of Viettel so that I use: e-connect. Mobiphone is: m-wap. Vinaphone is: m3-world, username: mms, password: mms.

Edit account informations




Note: Phone must is *99# (all of country)

Username and password in this case is empty. You must add two symbol (single quote) after them.

Ok, Press “Esc” key to exit edit mode of vi, Press “:” key, enter “qw” and enter to save file.

Step 6: Connect to the internet with D-COM 3G


Please wait a minute, when you see some IP in your terminal, you are done.

Try open new terminal and ping google dns to make sure you can connect to the internet:



cuongk6t – Nguyen Quoc Cuong.

Written by cuongk6t

19/06/2012 at 3:00 pm

How to install vmware vSphere 5 (ESXi 5)

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Figure: Loading ESXi Installer


Enter to Continue


Press F11 to Accept and Continue



Use Arrow Key to select a Disk, Press Enter to Continue


If the Disk cannot be preserved, you can see a warning message. Press Esc to select another Disk or Press Enter to continue (Be Careful, all existing data on disk will be lost)


If the Disk contains an installation of ESX and a VMFS datastore

Select install ESXi (by spacebar), overwrite VMFS datastore (in my situation).

Select keyboard layout and press Enter to continue


Enter root password and Enter


Waiting for system scan


Press F11 to Confirm Install


Install process





cuongk6t – Nguyen Quoc Cuong

Written by cuongk6t

09/05/2012 at 10:30 am

How to install Xampp on CentOS6 x86-64

with 4 comments

Step1: install CentOS 6, with “Basic Server” option (console mode, without graphic)


 After install, reboot system.

 Step 2: Test wget packet was exist.


ok, that’s good.

 Step 3: Install Xampp

(Open Console and login with root),

a. Download xampp for linux from this , now, it have “XAMPP Linux 1.7.7” version.

# wget

b. Extract the downloaded archive file to /opt:

#tar xvfz xampp-linux-1.7.7.tar.gz -C /opt

That’s all. XAMPP is now installed below the /opt/lampp directory

Step 4: Check xampp start correctly or incorrectly and fix errors

To start XAMPP simply call this command:

/opt/lampp/lampp start

We got an error: 


OK. We must fix it

Step 1:

#vi /opt/lampp/lampp

Find this lines:

# XAMPP is currently 32 bit only
case `uname -m` in
if /opt/lampp/bin/php -v > /dev/null 2>&1
$de && echo “XAMPP gibt es zur Zeit nur als 32-Bit Applikation. Bitte verwende eine 32-Bit Kompatibilitaetsbibliothek fuer Dein System.”
$de || echo “XAMPP is currently only availably as 32 bit application. Please use a 32 bit compatibility library for your system.”


Press “I” to edit (insert # in the begin of each line)



It’s mean: comment all of them.

Save it and quit. (:x or :wq)

Step 2:

Install all of 32 bit library missing:

#yum install glibc*

#yum install libstd*

Step 3:

Start xampp:

/opt/lampp/lampp start

OMG, still error:


OK, let’s fix: “line 91 : command not found”

#vi /opt/lampp/lampp

Press ESC and #:91  to go to line 91

OMG, my mistake when edit lines.  (^\), just delete it and save.



Start xampp again

/opt/lampp/lampp start

Next error: “bad ELF interpreter”



Fix it:

#yum install -y glibc*i686

Start xampp again

/opt/lampp/lampp start

Wow. It’s work.



cuongk6t – Nguyen Quoc Cuong

Written by cuongk6t

17/04/2012 at 3:46 pm

Posted in Linux Tutorial

Sinh nhat Kiet

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Written by cuongk6t

19/12/2011 at 4:46 pm

Posted in Uncategorized

Uninstalling vShield Service from ESX using Command line

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Today, I got into big trouble with vShield Zones where I need to remove them from ESX host. Generally, it would be done by using vCenter. In my case, I don’t have enough resources in another ESX host where I need to bring the ESX1 for maintenance mode in order to remove the vShield Service. Finally, I end up with using service console command to remove vShield service from ESX host.

# esxupdate query

————-Bulletin ID————- —–Installed—– —————–Summary——————

ESX400-Update01 2010-01-29T11:28:45 VMware ESX 4.0 Complete Update 1

VSZ200_vshield-dvfilter-module_285928 2010-10-04T09:49:17 Dvfilter fastpath module for vShield Zones
# esxupdate remove -b VSZ200_vshield-dvfilter-module_285928

Removing vshield-dvfilter-module #################################################################### [100%]
Running [/usr/sbin/]…


# esxupdate query
To verify the vShieldZone is presented or not.
Then, reboot the ESX host.


cuongk6t – Nguyen Quoc Cuong

Written by cuongk6t

17/12/2011 at 4:59 pm

initialization of module dvfilter failed

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Booting the ESX host fails with the error: initialization of module dvfilter failed

  • Cannot boot the ESX host
  • Booting the ESX host fails
  • You see the error:
    initialization of module dvfilter failed.
  • In the VMkernel logs, you see entries similar to:
    Nov 21 19:24:45 vm07 vmkernel: 0:00:00:43.939 cpu5:4110)WARNING: Elf: 3064: Kernel based module load of dvfilter failed: Failure
    Nov 21 19:24:45 vm07 vmkernel: 0:00:00:43.941 cpu0:4096)VMNIX: Logger: 481: sysboot: Failed to load dvfilter
    Nov 21 19:24:45 vm07 vmkernel: 0:00:00:43.949 cpu0:4096)VMNIX: Logger: 481: sysboot: 47.dvfilters returned unknown error code: 2

This issue occurs because the dvfilter module is not getting loaded.

To resolve this issue:

  1. Run this command to load the dvfilter module:
    #esxcfg-module –e /usr/lib/vmware/vmkmod/dvfilter
  2. In the ESX host, navigate to Configuration > Software and click Advanced Settings.
  3. Remove the IP address from /Net/Net.DVFilterBindIpAddress.
  4. Reboot the ESX host.



cuongk6t – Nguyen Quoc Cuong

Written by cuongk6t

17/12/2011 at 4:56 pm