Nagios Support Forum

Hi,
Apologies in advance, I am new to Nagios system administration and am trying to figure out which direction to go troubleshooting a problem that occurs sporadically. Nagios version is 5.5.8

Basically, we have some users who use the NRDP interface to run XML code which should trigger the generation of an email alert. As I say, this works most of the time, but will stop working. When this stops sending email, other users who are not using the NRDP component continue to receive email alerts with no problem.

An example of the XML code is:
When we click Submit XML Check Result, there is an OK confirmation, and an email is sent.
It has been reported that when email messages fail to send, the NRDP interface also doesn't return an OK after clicking Submit XML Check Result.

On one recent test where an email failed to send, it did arrive after the machine was rebooted, possibly it is queueing somewhere, but we haven't been able to work out if there is a queue of emails and how it can be monitored.

We have monitored phpmailer.log and maillog but are not sure specifically what to look for.

I apologize for the lack of details and specifics here, but if you can point us in the right direction for logs to check, information to capture, etc.. we will know what to check/capture next time to help narrow this down.

Thanks in advance.

Luke

I think perhaps these three KB articles might be worth checking:

https://support.nagios.com/kb/article/n ... p-795.html
https://support.nagios.com/kb/article/n ... d-416.html
https://support.nagios.com/kb/article/n ... s-480.html

This may help understand email settings:
https://support.nagios.com/kb/article/n ... g-585.html

Double Post - sorry

Thanks for your reply. I checked the articles and found that none of them applied:
[*] Permissions on /usr/local/nagios/var/spool/checkresults are set as: drwxrwsr-x 2 nagios nagios 8192 Jan 8 11:52 checkresults
[*] The group nagcmd contains the following: /etc/group - nagcmd1002:nagios,apache,snmptt
[*] php-xml is already installed: php-xml-5.4.16-43.el7_4.x86_64

In terms of email settings, the system is using sendmail by default. As mentioned, email does work for a while before it comes to a halt for the users using NRDP only. All other Nagios users continue to recieve email from Nagios and have not experienced any email problems like this.

Thanks again,

Luke

assuming that the nrdp part is working properly, and firing to nagios - then i think the issue lies in mail somewhere.

if you're using sendmail by default, and not a smtp server, then the phpmailer log is irrelevant as this is only used for smtp based settings.

these two files might contain a timestamp, or more information around a throttle at a queue layer for sendmail: do these NRDP alerts send a lot of emails out generally? any chance they could be flooding by chance?

Thanks @tacolover101!

@dpsupport, @tacolover101 is correct. Check the mail logs for clues. It's possible that emails sent via sendmail were not delivered (got bounced).