Category : Network


Most distributions of Linux come with a handy network latency utility called mtr.  Thankfully, it is included with the distributions of RHEL we use as well.  It’s a combination of ping and traceroute which show each hop of a network path, the time for that hop, and averages/standard deviations.  I use it all the time.  ..

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To view the existing routes, C:\> route print To add a static route, Syntax: C:\> route add <target> mask <netmask> <gateway IP> metric <metric cost> if <interface> Example: C:\> route add 10.10.10.0 mask 255.255.255.0 192.168.1.1 metric 1 Note: If there is more than one Network Interface and if the interface is not mentioned, the interface ..

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This is a simple script that interactively converts an IP address to its decimal equivalent. This can sometimes be used to bypass web content filtering devices as not all will convert the decimal to an IP and then a hostname. #!/usr/bin/perl # # prompt for an IP print “Enter an IP Address: “; # get ..

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1. Determine what existing range files exist: # cd /etc/sysconfig/network-scripts/ # ls ifcfg-eth1-range* You will see at least one file, possibly several. Find the highest number following the “range” and add one to it. This will be the new range number. For example, if you see ifcfg-eth1-range0 and ifcfg-eth1-range1, your new range number will be ..

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Possible telnet test output for another database and their meaning is listed below: a) Result when firewall is blocking connection for a IP and port combination: >telnet 20.25.127.140 3306 Trying 20.25.127.140… telnet: Unable to connect to remote host: Connection timed out b) Result when firewall is allowing connections through for IP address and port number ..

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