Alerts not generating between specified time

[wiproltdwiv]

Dear Team,

As we are getting problem in alerts generation. Main issue is the alerts are not generating between specified time(Between 11 am to 14 pm). it does fluctuate also sometime between 11 am to 13 pm ,11 am to 12 pm, 12 pm to 14 pm. This is happening frequent. This is happening for all domain which has configured in nagios like Network,Linux,Windows,AIX etc.
For this i analyzed nagios logs ,databases health, mysqld logs everything seems ok. That's why i am not able to find the root cause for this. Please find the attachment for your reference . I have given status of 03-12-2015 between 13 pm to 14 pm.

Please suggest solution so that we can resolve this issue as soon possible. So that we can have proper report.

[rkennedy]

I'd like to help, and with that said I need to gather a bit more information.
- Are the checks still running properly between 11AM - 2PM or are they all timing out as posted in your screenshot?
- Is it just the notifications that aren't working at that time?
- Are you using sendmail or SMTP for alerts?
- Can you post the output of top|head -5 for us to take a look at?