Most network engineers and technicians are quickly discovering that with “everything over IP” we are required to understand exactly what this means. For a lot of the standard, traditional data communications between clients and servers this means transport over TCP. Furthermore, it requires the ability to troubleshoot TCP. To troubleshoot TCP you have […]
A Wireshark TCP Troubleshooting Configuration Profile Read More »
For those of you who love Wireshark and are supporting BGP, we would like to offer a great default profile for basic BGP. Consider for a moment what would be important in your network administration in basic BGP: Being able to filter BGP packets quickly, as well as finding potentially bogus BGP Colorizing BGP message
A Wireshark Basic BGP Configuration Profile Read More »
Check out these additional IPv6 Resources: Our IPv6 overview course at Udemy Our IPv6 Custom Profiles for Wireshark Our IPv6 classes at the Online School For those of you who love Wireshark and are supporting IPv6, we would like to offer a great default profile for IPv6. Consider for a moment what would be important
A Wireshark IPv6 Configuration Profile Read More »
In this article, I will explain steps to correct a CONFIG_RESOLVE_FAILURE error in Cisco IOS. \If you are like many users of the latest IOS, you may find your routers constantly outputting a message like this: cell_pe1# %Error opening tftp://255.255.255.255/cisconet.cfg (Timed out) 19:20:43: %SYS-4-CONFIG_RESOLVE_FAILURE: System config parse from (tftp://255.255.255.255/cisconet.cfg) failed The reason for this message
CONFIG_RESOLVE_FAILURE error Quick Fix in Cisco IOS Read More »
Sometimes, we need to transfer IOS from one router/platform to another. Other times, we can end up in Rommon> prompt because an IOS download failed of similar issue. Let’s start with a stranded router. It is strongly suggested that you get a PCMCIA memory card, insert it into a good router. From priviledged mode on
Copying Cisco IOS from One Router to Another Read More »
Anyone who has network admin access can make changes to the running configuration on a router or switch at any time. If you are running a large IT shop or in charge of just a few folks, this feature will enable you to control the concurrent changes to your running configuration. Exclusive Configuration Change Access,
Configuration Lock in Cisco IOS Read More »
This How To discusses how to set up one Cisco Router as a PKI Server and one Cisco Router as a client. That’s right, you can set up a Cisco router as a Certificate Authority (CA) and then set up other routers as clients to use that CA to authenticate on your network. The advantage
PKI Server and Client Setup in Cisco IOS Read More »
CAR — or “rate limiting” — is a method for managing unwanted traffic on your network and making sure it doesn’t affect important traffic. Essentially, CAR controls the bandwidth of a certain type of traffic, and an access control list (ACL) defines which traffic it controls. Once you’ve created the ACL, you can set CAR
Committed Access Rate in QoS with Cisco IOS Read More »
As VoIP becomes more widely used in the enterprise, the number of voice calls traversing the enterprise WAN becomes larger and larger. Typically the use of a proper codec is implemented to reduce the amount of bandwidth a voice call requires. The most commonly used codec for WAN voice traffic is called G.729. While there
Compressed Real Time Protocol (cRTP) to Streamline Voice in Cisco IOS Read More »
Show Version is a great command for routers, switches or PIX firewalls. Here is a look at all the things you can verify with the show version command: On Routers Cisco switches PIX firewalls We hope this helps and saves you time finding all this information by putting it in one place! Comments are welcomed
Show Version Command in Cisco IOS Read More »
This How To will describe the most common configuration needed for Cisco IOS to create a DHCP (IPv4) server on your switch or router. Before You Start Before you configure the DHCP address pool, you need to: •Identify DHCP options for devices where necessary, including the following: –Default boot image name –Default routers –Domain Name
DHCP Server Configuration on Cisco IOS Routers Read More »
This short and sweet How To explains how to configure the DHCP Client in IOS. This is done using a single command. Go to the interface configuration: Router(config-if)#ip address dhcp Some service providers might ask you to use a client-id and/or a hostname of their own choice. This can be done by adding the following
DHCP Client Configuration on Cisco IOS Routers Read More »
When a router learns multiple routes to a specific network via multiple routing processes (or routing protocols, such as RIP, RIPv2, IGRP, EIGRP, and OSPF), it installs the route with the lowest administrative distance in the routing table. Load balancing is a standard functionality of the router software, and is available across all router platforms.
The Border Gateway Protocol (BGP) allows internal and external networks or autonomous systems (AS’s) to exchange routes. BGP is a path-vector routing protocol, which simply means that its job is to exchange routing information between autonomous systems to find the most efficient path for your data to the Internet. Each BGP router connects to its
Border Gateway Protocol (BGP) Path Selection Read More »
A common question folks ask is “How do you check the bandwidth utilization on a router?” It is a great question and the answer is not as easy as you would expect. There are tools that accomplish this (i.e. NetFlow and there is another mentioned at the end of this page). However, without those tools,
Bandwidth Utilization – How to Check It on Routers Read More »
