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Hosted Zimbra Email Catches On With Managed Service Providers

Saturday, 19 July 2008
MSPmentor: "When it comes to hosted email, why zig when you can zag? That explains the strategy at EtomicMail, a managed service provider that’s hosting Zimbra — an open source email platf

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Perl and Bash Versions Of Binary To Decimal Conversion Script

Saturday, 19 July 2008
The Linux and Unix Menagerie: "As promised, in yesterday's post on converting binary values to decimal in C, today we're going to follow up with straight-up ports to Perl and shell. Actually, they'll

E4X: JavaScript on Steroids

Saturday, 19 July 2008
IBM Developerworks: "E4X is designed to simplify the task of writing JavaScript code for XML. It is an efficient, powerful tool that you can use to interact with XML nodes and attributes. The primary

Linux 2.6.26 Kernel Benchmarks

Saturday, 19 July 2008
Phoronix: "Over the weekend the Linux 2.6.26 kernel was released. This quarterly update to the Linux kernel introduced Kernel-based Virtual Machine improvements, new One Laptop Per Child support, a ne

Latest Digg Entries

Detecting to see if a mail server is still alive using a simple shell script

« H E email
posted Thursday, 31 August 2006
Using the Linux utility, nc, you can write a small script to test for the existance of a given mail server and then take action if it appears not to exist.
#!/bin/bash

TEST_SERVER=127.0.0.1
TEST_PORT=25
OUTPUTLOG=/tmp/testoutput.txt

rm -f $OUTPUTLOG

# Gather the connection details
/usr/bin/nc -zv -w 15 $TEST_SERVER $TEST_PORT 1&> $OUTPUTLOG

if grep "succeeded" $OUTPUTLOG; then
  echo 'Server is up'
else
  echo 'Server is down'
  echo 'do something here'
fi
The nc utility is a very powerful little utility that can be used for a variety of uses, including acting as a server for incoming connections.

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