Thursday, August 30, 2007

Remove GRUB loader

Sometime we need to have 2 operating systems, e.g. ubuntu+windows xp.
Install XP first, then install Linux. But maybe later on, we want to delete the linux and its partition. After we delete, we cannot access the windows XP! GRUB loader error? What should we do?

Don't worry, you can have your XP back as long as you don't delete the partition. Grab your windows XP cd, and boot from your windows XP cd, same as if you want to install XP. Then wait until it asks for options. Choose Recovery Console by pressing 'R'. Then the screen will becomes black, then wait. Choose the windows you'd like to recover. Usually the first one, then input the number '1'.
You will now on command prompt: "C:\WINDOWS"
do these commands below:
- cd ..
- fixboot c:
- fixmbr
- bootcfg /rebuild

After that type exit, enter then your PC will be rebooted. If it's working properly, usually you will boot to your XP again. Good luck!

Tuesday, August 28, 2007

Root Password in Ubuntu

How to change the 'root' password in Ubuntu?
When we are installing Ubuntu it doesn't ask about su (super user) and its password, only user name and password for logging in as a normal user. After installing Ubuntu, when we want to install or access '/', we asked to log in as 'root'. To have full access in Ubuntu, we must logged in or do the commands as 'root' user. What is the default password for 'root'?

As default Ubuntu has no password set for the root user. To gain 'root' access, we just add sudo in front of our commands
e.g. #sudo tar xvfz xampp-linux-1.5.3.tar.gz -C /opt

But sometimes it is disturbing, because after executing commands with sudo added in front of it usually it asked for the password (the same password we have inputted when installing the ubuntu).

Easier option is to log in as 'root' user. Because the default the 'root' user has no password, we can manually set the password by opening the terminal and executing:
$ sudo passwd root
Ok, now you can logged in as root or su.

Saturday, August 18, 2007

Cisco Certification (CCNA)

Many of my friends asked me about Cisco Certifications. Bay, do you take the Cisco Certification? How can I get it? When should I take it? They ask questions like that and usually they think there's only 1 Cisco Certification which is not true. For further explanation, we can directly navigate the Cisco Systems, Inc website. But people prefer to ask directly to someone who knows about it or read articles about the certification in general. I'd like to explain a bit about the Cisco Carrer Certifications & Path especially CCNA. So, for masters/seniors who read this posting please correct me if I got it wrong. I'm still a college students, sorry if make mistake in my explanation, thanks.

Cisco Systems offer three levels of certification:
  1. Associate
  2. Professional
  3. Expert
The Associate level includes the new CCENT certification. The Expert level includes the CCIE certification, which represents the highest level of achievement.

It has six different paths:
  1. Routing & Switching
  2. Design
  3. Network Security
  4. Service Provider
  5. Storage Networking
  6. Voice
So that we can match our certification path to our job role or industry.

While in focused areas, network professionals can enhance their core networking knowledge by achieving specialist certification in technologies such as security, IP telephony, and wireless.

The first step in general Cisco Career Certifications begins either with CCENT as an interim step to Associate level, or directly with CCNA for network operations or CCDA for network design.

Why become a CCNA?

The CCNA program was created to provide a solid introduction not only to the Cisco Internetwork Operating System (IOS) and Cisco hardware, but also to internetworking in general. Ok, I will try to explain the first level only which is Associate. The CCNA certification was the first in the new line of Cisco certifications, and was the precursor to all current Cisco certifications.

How do you become a CCNA?
There are 2 ways:
  1. Pass either 640-801 CCNA exam or 640-802 CCNA exam.
  2. Pass both 640-821 INTRO & 640-811 ICND or 640-822 ICND1 & 640-816 ICND2
640-802 CCNA, 640-822 ICND1 and 640-822 ICND1 exams are new curricula. According to some news from Cisco website, after November 6 2007, there will be no 640-801 CCNA, 640-821 INTRO and 640-811 ICND exams.
New Exam questions have been updated to validate the skills necessary to implement today’s small to medium-sized branch networks, and include new topics, such as network address translation and IPv6, basic security controls, and basic WLAN concepts. A full list of exam topics is provided at www.cisco.com/go/ccna. The new exams also feature more performance-based questions, to better assess candidate competency.

Cisco has created another certification track for network designers in Associate level. The two certifications within this track are the CCDA (Cisco Certified Design Associate). To achieve this, we must pass the Design exam (640-861). To pass this test, you must
understand how to do the following:
  • Design simple routed LAN, routed WAN, and switched LAN and ATM LANE networks.
  • Use Network-layer addressing.
  • Filter with access lists.
  • Use and propagate VLAN.
  • Size networks.
The Cisco CCENT (Cisco Certified Entry Networking Technician) will certify the practical skills required for entry-level network support positions. The new certification validates the ability to install, operate, and troubleshoot a small branch network, including configuring a router and switch, connecting to a WAN, and implementing basic network security. It is a tangible, but optional, first step in earning the CCNA certification, the foundation-level certification for networking careers. Recipients of the new certification also gain access to the Cisco Certification community, which enables them to access additional training resources and use the new CCENT logo to indicate their achievement.
To achieve the entry-level CCENT certification we must pass the ICND1 640-822 exam. Taking the INTRO 640-821 exam will not qualify us for the CCENT certification.

CCNA certifications are valid for three years. To recertify, either pass the current CCNA exam, or pass the ICND2 exam, or pass any 642 professional level.

To pass the exam, we should have trainings or study from book like Study Guide books published by Sybex or Cisco Press. There are 3 ways to be prepared for CCNA
  1. Exam Preparation 640-801 CCNA or 640-802 CCNA
  2. Exam Preparation 640-821 INTRO & 640-811 ICND or 640-822 ICND1 & 640-816 ICND2
  3. CNAP-CCNA (Cisco Networking Academy Program), this is a CCNA Courses 1 through 4 of the Academy program, equivalent to 280 hours of instruction, provide students with a basic foundation in networking. Students who successfully complete this portion of the program are eligible to earn Cisco Certified Network Associate (CCNA™) certification. The first four courses are available at the secondary and post-secondary levels. This Networking Academy covers the knowledge in networking starting from Networking Basics, Routers & Routing Basics, Switching Basics & Intermediate Routing until WAN Technologies. Cisco recommends taking the CCNA exam after completing these courses of the CCNA curriculum.
References: