Category Archives: Network Troubleshooting

What is Syslog? Syslog Explained.

System Message Logging – SYSLOG Modern network devices has advanced from simple transmitting of messages (email.documents, multimedia etc), network devices like Cisco routers and switches provides the features for network administrators to reading system messages from their internal buffer about  network situation at a particular time. The way do this is by using Syslog server. Cisco network devices (Routers… Read More »

Troubleshooting VTP: Server as Client error and Solution

Accidentally Set Server Switch as VTP Client Solution. Mistake happens,  As a network administrator you can mistakenly configure operating mode of the server switch as VTP client. Only Server switches can create, delete, and modify VLANs. By reconfiguring the sever switch to VTP client mode, you lose all ability to create, delete, and manage VLANs within your network environment,… Read More »

What is Cisco Discovery Protocol – CDP? Explained with Examples

Cisco discovery protocol is a layer 2 protocol (OSI) that operates between Cisco devices such as Router and switches. CDP displays information about the directly connected devices such as device ID, Platform, connected interface, IOS versions, and layer 3 IP address. We use the network topology below as an example Topology Configuration HQ#config t HQ(config)#interface fa0/0 HQ(config-if)#ip address… Read More »

What are Common Network Security Threats?

Three common factors emerges when dealing with network security, these are vulnerability, threat, and attack. Vulnerabilities An experienced hacker knows that every network or device has a certain degree of vulnerability or weakness, and they take advantages of each security weakness or loophole to exploit the network.  A  Computer network hackers work round the clock in search of unsecured… Read More »

What is Denial of Service? Explained with Examples

DoS attack prevents authorized users from using services by consuming system resources. Most times DoS attack is regarded as trivial but in a sense it is a consequentially threat. DoS can cause potential damage to networks. Not only are they easy to execute, but its among the most difficult to eliminate. DoS attacks deserve special attention from network… Read More »

Troubleshooting Access Point Misplacement Error and Solution

Identify Problems with Access Point Misplacement. You may have experienced a WLAN that just did not seem to perform like it should. Perhaps you keep losing connection with an access point, or your data rates are much slower than they should be. You may even have done a quick move around the environment to confirm that you could actually see… Read More »

Troubleshooting VTP Error: Incorrect Revision number solution

There are other factors that can undermine your network even after you have configured the switches in your VTP domain correctly. They can adversely affect the functionality of VTP. The topology diagram below is configured with VTP. There is one VTP server switch, SW1, and two VTP client switches, SW2 and SW3. SW1, SW2 and SW3 are configured with the same VTP domain… Read More »

Troubleshooting VTP

VTP Domain Name Error and Solution A VTP domain consists of one or more switches interconnected together under the same administrative responsibility sharing the same VTP domain name. An improperly configured VTP domain affects VLAN synchronization between switches. That means they will never share VLAN information. A switch drops any wrong VTP advertisement it receives, even if it contains legitimate configuration… Read More »

Troubleshoot Wireless Network: Channel Setting Error and Solution

Most WLANs today operate in the 2.4 GHz band, which can have as many as 14 channels, each occupying 22 MHz of bandwidth. Energy is not spread evenly over the entire 22 MHz, rather the channel is strongest at its centre frequency, and the energy diminishes toward the edges of the channel. Interference can occur when there is overlap of… Read More »

What Network Attack? Trust Exploitation

 What is Trust Exploitation Attack? The goal of a trust exploitation attacker is to compromise a trusted host, using it to stage attacks on other hosts in a network. If a host in a network of a company is protected by a firewall (inside host), but is accessible to a trusted host outside the firewall (outside host), the inside… Read More »