Tag: network

  • How to add/modify IP Address in Redhat Enterprise Linux

    Adding the IP Address in Redhat Enterprise Linux can be done by using the netconfig tool or by editing the network-scripts or by using the ifconfig command. While this procedure is tested on Redhat Enterprise Linux, I'm sure it should work on CentOS, Fedora and older Redhat versions.

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  • mturoute – Free utility to find the MTU Value to a host or IP Address

    One of the most important thing that is ignored most of the time while troubleshooting a network problem to a host or a network is checking the MTU related issue. This makes more sense in situations like troubleshooting VPN related issues.

    MTUROUTE is a small but smart utility that uses ICMP pings of various sizes in order to determine the MTU values (Maximum Transmission Unit) on the path between itself and the target system. MTUROUTE can operate in normal mode where it sends multiple ICMP packets to each hop on the path to identify the smallest MTU between the host and hop or in a Traceroute mode where it will attempt to determine the lowest MTU between the local host and each hop in the communication.

    It is important to note that care has to be taken as it generates muti fold ICMP traffic as it tries to determine the MTU Values.

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  • ICMP Redirect messages from a gateway router

    ICMP Redirect is a type 5 ICMP error message sent by a gateway router to a sending host informing of an optimal alternate route to the destination host and to update its routing table with the new host route to the target destination host. The router forwards the original packet to the next hop router or to the destination host and sends the ICMP Redirect message to the sending host so that the subsequent packets to the destination host can be sent via the new route.

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  • Ziptie – Opensource Network Inventory & Configuration Management Framework

    Ziptie is an Opensource Network Inventory and Configuration Management framework that can discover and manage network devices such as Routers,Switches and Firewalls. Ziptie out of the box support network devices from multiple major vendors. Ziptie is java based and is built on Eclipse framework. Ziptie can run on many Operating System platforms including Windows, Ubuntu, Fedora,Redhat, Madnriva amd most other Linux Distributions.

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  • SNMP configuration on Cisco IOS for routers and switches

    SNMP helps monitoring your network devices wherein it can help a Monitoring System to query the device about various system health and/or modify configurations based on the permission it has on the device or on the other hand, allow the device itself to send alerts (known as trap in SNMP) to the management system of any system issues like a PSU failure.

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  • Fping for Windows

    Fping is a free console program, much like the ping program that comes with windows.

    Why use fping instead of the standard windows ping?

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  • fping – Ping multiple hotsts at once

    fping is a ping like program which uses the Internet Control Message Protocol (ICMP) echo request to determine if a host is up. fping is different from ping in that you can specify any number of hosts on the command line, or specify a file containing the lists of hosts to ping.

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