SPAN (Switched Port Analyser) is a requirement whenever you have a system that wishes to log and monitor traffic that is passing through a switch. Since a switch only sends traffic to the machine requiring the packets, adding a sniffer to the switch would result in you only seeing traffic to your sniffer, from your [...]

As part of any management and audit solution for networking, Syslog is vital.
 
Syslog messages allow us to track system error messages, exceptions, and other information, such as device configuration changes.
It allows for historical reporting, depending on the application keeping the logs, as well as help in fault finding.
 
Cisco devices support 8 levels of logging information [...]

In the event that you have lost the configuration on your Cisco device, restoration is straight forward assuming of course you had made a backup. There are 2 ways to restore the configuration to put our device back to normal
 
                1/ Copy and paste the backup configuration directly to the device
                2/ Copy the configuration [...]

Cisco brings out new versions of the operating system quite frequently, and of course there are different versions of the operating system for each of the appliances. Different IOS’s will support different commands and different features and it’s not uncommon to have to change the IOS that your device is running to support commands you [...]

The first and most important rule in IT, is “Backup soon, Backup often!”
It’s a logical statement but sadly one that many people only truly appreciate when it’s too late!
 
Two of the most important files on a Cisco router are the Running-Config which stores the current configuration of your router, and the IOS (The operating system) [...]

Cisco offers a password recovery technique for almost every device they have available. In this post, I’m going to cover how to complete a password recovery on a Cisco router.
There are 2 things that have to be in place before a password recovery can be done.
1/ Physical access to the router
2/ A console connection to [...]

Additional configuration to further lockdown Cisco router security.

In most smaller networks, or networks that have a few network administrators, when you log into a Cisco device you are only prompted for a password. This will take you to the Router> prompt where more than likely you will immediately type ‘enable’ to enter into privileged exec mode, and you will be prompted with [...]

Secure Shell (SSH) is a protocol that allows us to connect to devices securely by using encryption. Gone are the days were most networking engineers are happy with using plain telnet with it’s clear text transmission of data which could result in an attacker sniffing the line for usernames and passwords.
Configuring SSH on a Cisco [...]

DHCP (Dynamic Host Configuration Protocol) allows a server (in this scenario a Cisco router) to issue IP addresses to computers on the network dynamically. This is not a great solution for servers, which should have static IP addresses, but for client computers needing access to the network quickly and easily, this is certainly a great [...]