Hi Guys, If you have mail command available then using it in a shell script is not that difficult, If a guy like me can do it anyone can I guess because I am not a native Linux man :) Anyway lets check how to do it I saved above as jasmail.sh As you will notice that I am using the heredoc syntax in the above script. There are sometimes that you want to send custom email messages so accepting the message from command line param makes sense so here is a little modification to the above script so that you can make use of it if you think that it could be useful Alternative So as you can see that in the MSG container I've use ${1} bit which means that the first command param becomes my email message as shown below That makes sense I guess. This is just a basic bash script, the Linux Gurus reading this post will have more to share if they wish to leave their feedback. One last bit, do not forget to give execute permission to the current user else you will not be able to use above bash script. I hope this will help or at least give you an indicator that will serve towards your final result/requirement Cheers … [Read more...]

Hi Guys, My Apache Web-server was playing up a little bit so until I found the cause of it my priority was to keep it up and running so I wrote a bash script to keep an eye on httpd crashes Lets check it out First up is to pick a script name and named it as httpdmon.sh and it is stored in my /home/jas/ directory CronJob Next I would just set a cron job so that it runs every minute and restart/start the service if required.  Basic Script Above script is good and as you can see that I am using curl to shoot a request to my local website and if the request times out i.e. after 5 seconds then an attempt to restart the service is made Now thats Ok but I would also like to be notified about it and also would like to force kill httpd process if for some reason it hangs A little bit more added to above script As you can see that above will send me a message, you can replace mail command with sendmail etc its up to you. Running that solved few of my issues until I figured out what is causing httpd to crash. If I found something interesting I will be sharing it with you guys. Please note: I am not a Linux Advanced user but just knows enough to do some basic to intermediate things. If you have something to add to would like to improve above script please leave your comments as it would help others. Cheers, … [Read more...]

Hi Guys, Just a quick one here, If you want to know size of a directory/folder you can use du command which is short form to disk usage You can cd to that directory and run this command Forget about the fact that I am logged in as root, I was just doing some weird things. Option 1 Option 2 or Now the above commands will print fill directory size but just in case you want to list sub directory size separately then this is how you do it   You can also specify directory path as shown below Above will work on /home/web folder You can also get quite interesting but if all depends what you are trying to do just type to see what else you can do here is a quick link to man page available through http://unixhelp.ed.ac.uk/CGI/man-cgi?du Above listed is just to give you an indicator Linux is so wide with its commands that there could be another 10s of combination to achieve above results but I am not not aware of those 10s so I rely on the above mentioned commands :) I hope this helps Just in case you would like to add something to this post or want to correct improper use of a command please leave your comments Cheers … [Read more...]

Hi Guys, To start with I am intermediate user of Linux and use RedHat at work and Ubuntu at home. I had this job where I have to search my apache server logs for some "text". Count the number of lines that have this "text" in them. Well I know basic shell scripting so I just used a bit of basic commands to get what I wanted. If you know other better solution please leave yours in comments. So DIRPATH above holds path to my access logs directory and I am iterating over to get line count of files one by one and my COUNTTOTAL variable holds the overall count. Above example show to count all lines and summing the output. In the example below lets make a slight change and search for a string "abc.com" and see how many lines have this string present. As you can see that we now are searching text "abc.com" in a file and piping the output to wc command adding the output to our global variable COUNTTOTAL and printing it using echo command. you should change DIRPATH to suit you. You can use the same fundamentals to create a dynamic list of file e.g. count the number of lines for files that are younger than 30 day, and iterate over them. We have used the following command in our shell scripts and each of the one have link to their manual page grep wc cut As my mate David Overton pointed out that above can be achieved without a script so here are our shell commands to do exactly the same thing. I think I am just stuck with scripting mind frame :) First command (equivalent to first script): Second command (equivalent to second script) : I hope that this helps. If I made any mistake please let me know. Cheers     … [Read more...]