GNS3 Video Course

Introduction
From our perspective as GROOK.net team, we would like to share our knowledge with world. We will start a GNS3 Course. We will use best methods to explain this software using videos as well as text documents in GROOK.net.  We will discuss each lesson in GROOK.net forum to share the knowledge.

What Is GNS3?
GNS3 is a graphical network simulator that allows you to easily design network topologies and then run simulations on them. At the moment GNS3 supports IOS

What is Dynamips ?

Dynamips is a project to emulate a Cisco 7200 on a traditionnal PC. Now, it also supports Cisco 3600 series (3620, 3640 and 3660), 3700 series (3725, 3745) and 2600 series (2610 to 2650XM, 2691)

Network Monitoring Software

The term network monitoring describes the use of a system that constantly monitors a computer network for slow or failing components and that notifies the network administrator in case of outages via email, pager or other alarms. It is a subset of the functions involved in network management

How To Have a Great Career

1- Take Ownership

• Your career is yours and yours alone. You have the power to create it and live it as an expression of your unique talents and energy.
• Forget what other people think of your choices. Even though people often mean well, you will be the one putting in the hours so be selfish enough to do something you enjoy and to have fun with it!

How to Use Technology to Switch Careers

There’s no reason why work has to feel like, well, work. While it’s a tough market out there, the good news is there’s no better time than now to reinvent yourself and your career.

What is Denial of Service?

DoS (Denial of Service) is simply rendering a service incapable of responding to requests in a timely manner. This is a controversial subject, since some people think that DoS is not a hack, and/or is rather juvenile and petty. We prefer to think of them as just one

What are common accounts and passwords for Unix?

All Unix systems have an account called root. This account is also commonly known as the superuser. Actually, any account with a user ID (UID) and group ID (GID) of zero could be considered a superuser account. It is possible that a system administrator will rename the root account for obfuscation, but this is rather impractical as many applications not only require that there be an

autocad drawing commands

Understanding /etc/passwd File Format

/etc/passwd file stores essential information, which is required during login i.e. user account information.

/etc/passwd is a text file, that contains a list of the system's accounts, giving for each account some useful information like user ID, group ID, home directory, shell, etc. It should have general read permission as many utilities, like ls use it to map user IDs to user names, but write access only for the superuser (root)

Linux Unix /etc/shadow file

/etc/shadow file stores actual password in encrypted format for user's account with additional properties related to user password i.e. it stores secure user account information. All fields are separated by a colon (:) symbol. It contains one entry per line for each user listed in /etc/passwd file Generally, shadow file entry looks as follows