Monitor your passenger applications via SNMP

Basic Idea:

Monitor the output of the command passenger-status, "Active Sites, Total Running, and Waiting Sites"

On your production box:
ubuntu@prodweb01:~$ cat /home/ubuntu/scripts/  
# Monitor Passenger-status by outputting to a file
# then grepping the variables and outputing them to seperate files
# you must add your own ruby path variables. 

export PATH=""  
greping=( max count active inactive )  
$cmd > $outputdir/$mainfile

for item in "${greping[@]}"  
    egrep ^$item $outputdir$mainfile | awk -F"=" '{print $2}' | sed 's/ //g' > $outputdir$item.txt

egrep ^$wait $outputdir$mainfile | awk -F":" '{print $2}' | sed 's/ //g' > $outputdir$wait.txt  

Add those files to snmpd for zenoss to read.

root@prodweb01:~$ cat /etc/snmp/snmpd.conf  
extend QUEUE /bin/cat /home/ubuntu/scripts/monitor/passenger/waiting.txt  
extend ACTIVE /bin/cat /home/ubuntu/scripts/monitor/passenger/active.txt  
extend COUNT /bin/cat /home/ubuntu/scripts/monitor/passenger/count.txt  
extend INACTIVE /bin/cat /home/ubuntu/scripts/monitor/passenger/inactive.txt  
extend MAX /bin/cat /home/ubuntu/scripts/monitor/passenger/max.txt  

Set the script to run every 5 minutes so zenoss can graph something

root@prodweb01:~$ crontab -u root -l  
*/5 * * * * /home/ubuntu/scripts/

Now restart snmpd and do a quick cat on the files to show that they are outputting data.

root@prodweb01:~$ /etc/init.d/snmpd restart  
root@prodweb01:~$ cat /home/ubuntu/scripts/monitor/passenger/* | head  
On your Zenoss box

Run the command:

[root@zenoss ~]# snmpwalk -v 2c -cYOURGROUP 111.222.333.444 NET-SNMP-EXTEND-MIB::nsExtendOutput1Line
NET-SNMP-EXTEND-MIB::nsExtendOutput1Line."MAX" = STRING: 200  
NET-SNMP-EXTEND-MIB::nsExtendOutput1Line."COUNT" = STRING: 147  
NET-SNMP-EXTEND-MIB::nsExtendOutput1Line."QUEUE" = STRING: 0  
NET-SNMP-EXTEND-MIB::nsExtendOutput1Line."ACTIVE" = STRING: 0  
NET-SNMP-EXTEND-MIB::nsExtendOutput1Line."INACTIVE" = STRING: 147  
[root@zenoss ~]# snmpwalk -v 2c -On -cYOURGROUP 111.222.333.444 NET-SNMP-EXTEND-MIB::nsExtendOutput1Line
. = STRING: 200
. = STRING: 147
. = STRING: 0
. = STRING: 0
. = STRING: 147

Thats an O for Orange, not a Zero.
Side Note: The redacted XX's are the ASCII HEX values. MAX == 77.65.88. (I am so glad I did this blog post :P)

Now You have your MIB ID's for your COUNT QUEUE ACTIVE and INACTIVE and MAX, you can easily add it to your Zenoss/Nagios. Make sure also that you "Override Template Here" and set it as /Device, and then it will turn it from saying (/Devices) to (Locally Defined). Otherwise you will add all of your MIB points to every server you operate.

Tim Coombs

Administrator of and world leader of my own mind, the only place our ideas and thoughts are our own in a world gone mad

In a terminal

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