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Below is a short script designed to output the addressable IP addresses within a given subnet. Note : This script requires the netaddr python library. #!/usr/bin/pythonimport sysfrom netaddr import IPNetworkIPADDRESS = raw_input(‘Enter Subnet:’)try: for ip in IPNetwork(IPADDRESS).iter_hosts(): print ‘%s’ % ipexcept: print “Usage: “,sys.argv[0],”[SUBNET ID]/[NETMASK]” print “Output addressable ip addresses within a given subnet.” … Read more
To extract or open RAR files within Linux the unrar binary is used. Below provides the installation and basic operational syntax for the unrar program. 1. Installation 1.1 REDHAT yum install unrar 1.2 UBUNTU apt-get install unrar 2. Basic Syntax To extract a RAR file the following syntax is used: unrar e contents.rar 3. Example … Read more
When Installing Ubuntu from a Live CD via the graphical installer ubiquity you may receive the following error : The username you entered is invalid. Note that usernames must start with a lower-case letter, which can be followed by any combination of numbers and more lower-case letters. Solution This error can occur … Read more
Traffic reporting on the Juniper Netscreen can be achieved via a number of methods. Various tools and features are available such as the Netscreen Security Manager (NSM), 3rd Party applications along with numerous reporting features on the device itself. This article will look at how to create traffic reports by using just 1. a Netscreen … Read more
Though Cygwin provides the ability to update and install packages via the use of the Cygwin`s setup.exe command, the command line installer apt-cyg provides apt-get like syntax whilst still using Cygwin’s native package repository. Below details the steps required to install the apt-cyg command line installer. 1. UPDATE CYGWIN First of all you … Read more
Link State Tracking is a feature (within Cisco Switches) that binds the link state of multiple interfaces. This provides the ability to “down” interfaces based upon the link state of upstream interfaces. The diagram below shows a simple of example of an scenario where link state tracking would be required. As you can see from … Read more
Introduction DMVPN (Dynamic Multipoint Virtual Private Network) is a feature within the Cisco IOS based router family which provides the ability to dynamically build IPSEC tunneling between peers based on an evolved iteration of hub and spoke tunneling. DMVPN uses a combination of the following technologies : Multipoint GRE (mGRE) Next-Hop Resolution Protocol (NHRP) Dynamic … Read more
The Windows 2008 Indexing Options can be located from with the Control Panel. In a number of instances you may find that this is not available or not installed. To install the Windows 2008 Indexing Service follow these steps: Start Server Manager via the Start Menu | Administrative Tools. Click on Roles (left navigation pane). … Read more
This is caused by additional carriage returns within your script. In Windows the end of a line is denoted by CRLF (Carriage-Return, Line-Feed). In Unix-like systems, the end of a line is donated by a single LF. This means when you try to run your script, every line has an extra carriage return which in turn causes … Read more