Resource utilization alerts shell scripts, Memory and CPU

Question

Hi All,
I am using the Oracle Enterprise Linux verison 4.6 x64 for Oracle 10g database. I want to implement some alerts for SWAP space thresholds, CPU comsumption and memory usage thresholds. For example I want an email alert is SWAP space is used 90%. Memory usage is more than 85%. CPU is 80% busy.
I am sure that you Gurus must have implemented this kind of alerts through some tools or shell scripts so seeking your help to implement these.
Thanks
Naveed

Answer 1

Hi Naveed,
Firstly, I can tell you that Oracle has its own SNMP MIBs which can be used by SNMP to send trap (alerts) to various SNMP monitoring systems. If however, you are a bit like myself and perhaps don't have the cash or the need to use something so fancy, you can use Shell Scripting or in my case something like PERL.
By using commands such as 'grep', 'awk' and 'less' (to name but a few) on can monitor simple things such as diskspace or memory.
For example, if I were to look for diskspace usage on a partition known as u01 I could pipe in the output of 'df -h' to PERL, then run a regular expression on it looking for anything greater than 80%.
Example of PERL code;
# read in df -h command, looking for the partition /u01
open(DISKUSAGE, "df -h | grep u01|");
$diskUse = <DISKUSAGE>; #read its input
chomp $diskUse; #remove last characterThis reads in the command into a 'buffer' in which you can search for things, i.e. to see if the disk usage is equal to, or greater than 80% from the variable $diskUse. As a starter I would look at splitting the string on empty spaces into an array for example, and reading the array index containing your disk usage. This can also be done with a Shell Script.
Perl also has a very easy to use SMTP module which can be used for sending E-Mails. Do a search for Net::SMTP on google on how to use it. It really is very simple.
I'm not expert on this stuff, and I'm sure there are many other and better ways of doing such things, but I hope this at least points you in the right direction.
Best of luck,
Conor