Welcome to CellStream’s Cisco Router and IOS How-To Resource Center. This collection of articles, configuration examples, troubleshooting guides, and practical tutorials is designed to help network engineers, technicians, students, and IT professionals better understand, deploy, manage, and troubleshoot Cisco networking equipment.
Whether you’re learning the fundamentals of Cisco IOS, configuring routing protocols, implementing security features, troubleshooting connectivity issues, or preparing for certification exams, you’ll find practical, real-world guidance based on industry experience and proven best practices.
The content provided here is intended to help simplify complex networking concepts and provide actionable solutions you can apply in your own environment. As with any network configuration, always validate commands and procedures in a test environment before implementing changes in production networks.
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Post Views: 1,912 The Web Cache Communications Protocol (WCCP) is used to redirect traffic (usually Web page requests) to another device in real time. The most common use for WCCP is redirecting Web traffic to a server that provides Web caching, filtering, or other services. You can enable WCCP on your router, but you should […]
WCCP Configuration in Cisco IOS Read More »
Post Views: 1,776 This How To explains the process of upgrading IOS on a Cisco Router. Before starting the procedure of IOS upgrade or installation, you will need to install TFTP server software on a PC connected to the router Ethernet interface. There are many free downloadable TFTP servers’ software on the Internet. Afterwards, you
Upgrading IOS on a Cisco Router Read More »
Post Views: 1,651 This How To explains username configuration. Short and sweet. Step 1: With use of below command we can create User in Cisco Router Cell_Router(config)#username AWALDING priv 15 password CELLSTREAM Step 2: Also, we have to enable this at each line Cell_Router(config)# line con 0Cell_Router(config-line)#login local Cell_Router(config)# line vty 0 15Cell_Router(config-line)#login local Cell_Router(config)# line
Username Configuration in Cisco IOS Read More »
Post Views: 1,556 Have you ever loaded a router with IOS that is too big for memory? If you have, then you have ended up in a problem and the router dumps you to ROM Monitor or ROMMON prompt. In this How To we weill explain what to do. There is a simple way to
Loading a Cisco Router from ROMMON prompt Read More »
Post Views: 1,472 In this How To we will explain the procedure for Warm Upgrade and Reload. The examples are shown on a Cisco 2811 Router. The warm upgrade feature of the Cisco IOS was offered in Cisco IOS version 12.3(11)T. The warm reload feature of the Cisco IOS was offered in IOS version 12.3(2)T.
Warm Upgrade and Reload in Cisco IOS Read More »
Post Views: 1,993 In this How To we will provide an overview of Smartports and how they can help with your Cisco switch administration. Cisco now calls these Auto Smartports. The Smartports macros can speed up deployment while ensuring accuracy and consistency on your switch ports. Simply put, Smartports macros are pre-created configuration scripts that
Smartports Macros for Switches in Cisco IOS Read More »
Post Views: 2,059 The ability to monitor your network traffic is critical for all network administrators and managers. This means getting down to the packet level. To get down to the packet level, you have to use a protocol analyzer that will dissect the packets and conversations that occur on the network. Most users are
Analyzing Traffic on a Cisco Switch Read More »
Post Views: 1,909 Here is what you need to know with regards to the Configuration Register in Cisco IOS. All Cisco routers have a 16-bit software register in NVRAM. The default is for Cisco routers to load Cisco IOS from FLASH MEMORY and to look for and load the STARTUP-CONFIG file from NVRAM. Some Reference
Configuration Register in Cisco IOS Explained Read More »
Post Views: 1,308 We are often asked about ICMP, and how it should be managed on a network. We hope this How To will explain this protocol a little and provide some initial guidance. What is ICMP? The Internet Control Message Protocol (ICMP) is part of Layer 3, not Layer 4 TCP, and it’s not
ICMP Management in an IPv4 Network Read More »
Post Views: 1,495 To save you time searching through thousands of documents and sometimes disjointed practices, here are some of our recommendations for securing Cisco routers. These practices can also be applied to other routers in general, though we provide no specifics for others. Security is always a concern to those who manage and configure
Security Setting Recommendations for Cisco IOS Routers Read More »
Post Views: 1,511 The Virtual Router Redundancy Protocol (VRRP) is a computer networking protocol that provides for automatic assignment of available Internet Protocol (IP) routers to participating hosts. This increases the availability and reliability of routing paths via automatic default gateway selections on an IP subnetwork. See RFC 5798. VRRP provides information on the state
VRRP Configuration on Cisco IOS Routers Read More »
Post Views: 3,237 This one is short and sweet. Is your traceroute responding with “* * *”, or did you enter 1000000000 for the number of extended pings? Easy – simply type CTRL-SHIFT-6 to break the process. That is the Control Key (hold down), the Shift Key (also hold down) and the “6” key –
Stopping PING or TRACEROUTE on Cisco IOS Routers Read More »
Post Views: 1,688 In this How To, we explain Cisco SNAT. Cisco SNAT allows two or more routers performing the NAT function as a group. This is really handy for redundancy purposes, and can be used in conjunction with Cisco’s HSRP function (click here to see how HSRP is configured). The NAT routers are going
Stateful Network Address Translation (SNAT) Feature on Cisco IOS Routers Read More »
Post Views: 2,192 Monitoring the traffic pattern on a network are essential in today’s network. If network administrators do stay on top of the traffic patterns, they may make crucial mistakes in network provisioning or design. With the Internet in a constant state of flux as new and hot applications emerge, this task becomes even
Netflow Basic Operations in Cisco IOS Read More »
Post Views: 2,113 How many times have I received a router that has no operating system on it? Way to many!! You turn on the router and it comes up in ROM Monitor mode (ROMMON). There is a way to get the operating system on the router from ROMMON. Below, I have documented the procedure.
Upgrading IOS on a Cisco Router in ROMMON Mode Read More »
