Post Views: 1,826 What happens if there is a system or user on a VLAN that is infected by malware or is deliberately running a scanning program? What if you have some public ports on your switches that you only want to have access to the Internet and not each other? This problem can be […]
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Post Views: 1,494 If you want to partition flash memory of routers with flash, you can. On most class B Flash file systems, you can partition banks of Flash memory into separate, logical devices so that the router can hold and maintain two or more different software images. This partitioning allows you to write software
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Post Views: 2,183 This How To explains Passwords on Cisco platforms. The question you might ask is: Doesn’t the router already have default passwords? The answer is NO, it doesn’t. There is no automatic password defense that comes with your router. As a Cisco admin, this should be taken very seriously. It is so important
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Post Views: 2,318 OSPF (Open Shortest Path First) is an IGP (internal gateway protocol), and OSPF is an open standard protocol originally defined in RFC 2328. Since then OSPF has been updated numerous times including functionality to support IPv6 and Address Families. OSPF is supported on every major routing platform as well as Windows Server
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Post Views: 1,954 Routine maintenance is the underpinning of any well run network. Through routine maintenance, consistency, predictability and standardization all result allowing the network to operate as expected and in times of fault, makes a better troubleshooting environment. As part of any routine maintenance activity, Cisco provides several commands to help. One less known
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Post Views: 4,399 You can use the service timestamps command to create timestamps on the router’s log files. Since version 11.3, the Cisco IOS has enabled certain timestamps by default, so most of us have this on. However, there are additional timestamps options that you can enable as well as places where timestamps are probably
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Post Views: 4,508 Whenever we teach our Hands-On courses, we always have a section of the course that discusses troubleshooting the network or technology the class is learning. A key part of troubleshooting any network is knowing the technology, no argument. But even the masters of technologies like Multicasting, or IP Networking, or MPLS, still
Leveraging Logging for Troubleshooting Using Cisco IOS Read More »
Post Views: 4,962 More than 60% of all truck rolls for Service Providers are related to Wi-Fi and Wireless LAN issues. From poor bandwidth performance to interference, issues abound. We offer the industry best, hands on training for Field Technicians, Customer Support Representatives, and technical staff that will elevate their understanding and save you money!
Wi-Fi and WLAN Skills that save money! Read More »
Post Views: 1,562 One of the most annoying things in Cisco IOS is its old roots in the 23 line terminals. Every 23 lines, you get a –More– pause, to which you have to hit the space bar to continue the output. Now maybe this does not bother you. Fine, move on to our next
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Post Views: 1,185 Many people are using VPN technology today to ensure data confidentiality between remote locations. When using a site-to-site type VPN (say between a Router and a Firewall), a common complaint among end users is intermittent delay before VPN traffic is successful. This is usually due to Security Associations (SA) becoming too old
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Post Views: 1,530 As many of our students and clients have learned, Spanning Tree in Layer 2 Ethernets is a basic control protocol that removes logical loops from physically looped networks creating the Spanning Tree. This How To focuses on the essential configuration commands in Cisco IOS that you need to know to manage Spanning
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Post Views: 2,218 All router administrators need to take whatever security precautions they can to prevent attacks to their systems and networks. While these attacks are a continually moving target, a common attack to IP networks is called IP Spoofing. This is accomplished by sending IP packets into the network with source addresses that appear
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Post Views: 1,795 IP mobility is software and hardware designed to provide network access as a user travels from network to network. Cisco calls this the ubiquitous connection. Cellular telephone networks already accomplish this: You can begin a cellular call in Los Angeles, CA and (in theory) you should be able to drive to New
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Post Views: 1,746 The following is a quick example on how to configure Cisco’s HSRP protocol. Many net admins ask about redundancy in Cisco routers and the answer is usually always the same: If your uptime has to be high, and the thought of having a failure and suffering the downtime that it will take
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Post Views: 1,464 Finding the right piece of information that you need from a Cisco router can often be a challenge. For example, if you use the show running-config command on a large production router, you can end up with 25 pages of text output. Locating that one piece of information you’re looking for can
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