Category Archives: cisco

Cisco IOS Fundamentals


Cisco’s IOS is a command line driven interface for all their devices. There are some basics for logging into a device. Such as physically connecting to the device console port with a serial port, or a roller over cable. For no i’m going to discuss the basic hierarchy to get into configuring the device. One of the most important commands to learn is the “?” command. At any time if you need to know the command that are available to you you can just type in “?”.

? output for user mode

The next thing you should know is the hierarchy into which you need to progress the get though to be able to configure the device i’ll try to make a simple table below.

Mode chart

To configure a device you must move through the hierarchy into the global mode. user>privilege>global. In the next image I’ll walk though these mode until a reach the interface mode.


Thank you for reading. I’ll definitely continue these article later.

Cisco’s IOS Overview


Cisico’s IOS operating system is very different from Apple’s iOS, and the two should not be confused. Ciciso’s IOS is an operating system design to work on very specific hardware, mainly routers and switches that Cisco sells. Is is a command line only system that runs with very low over head that means cisco’s equipment can be very efficient not worrying about user interfaces and graphical processing. That means the size of the OS is still remarkable small most versions of IOS are around 8 MB to Download and 32 MB to run. One of the requirements to download are registering with Cisco and having a service contract to actually run IOS on your equipment. It is generally not available to the public. While non tier 3 switches don’t need IOS, as their hardware is ASIC based. Tier 3 switches inherit functionality from routers and need knowledge of IOS to configure. One of the most interesting qualities of Cisco IOS and routers is the fact that they’re designed to require little or no user interaction in their service life. This “Bullet-Proof” quality of their products is important to most companies as networks are often the backbone that keeps the company working. All vital networks should have redundancies to deal with any issue that might come up. So who should use Cisco routing and switching gear? really most businesses that rely on their computer for daily business but we’re seeing more and more businesses that require solid networks in their locations like fast food restaurant integrating self serve POS terminal for their customers.