It could be that you have two nagios processes running. The following should take care of that.
What's the output of the following? Please note that you will need to remove the "#" before each command line for the commands to work.
# df -i
# df -h
It's possible you are out of space. If that's the case, please follow
https://assets.nagios.com/downloads/nag ... M-Disk.pdf
Please run through
https://assets.nagios.com/downloads/nag ... tabase.pdf and report any errors. If you stop at any point, please know at which point you stop.
If the repair script and other instructions in the document do not resolve the issue, please continue.
Regarding the instructions below, if you do not have killall, you can install it via the following command:
# yum install psmisc
If psmisc is not in your repos, then instead you can check to make sure nagios is not running with
# ps -aef | grep nagios
If that document does not resolve your issue, please run the following commands in order and report any errors. You ***must*** use mariadb instead of mysqld in the commands below, ***if*** you have mariadb.
# service nagios stop
# service ndo2db stop
# service mysqld stop
# service crond stop
# service httpd stop
# killall -9 nagios
# killall -9 ndo2db
# rm -rf /usr/local/nagios/var/rw/nagios.cmd
# rm -rf /usr/local/nagios/var/nagios.lock
# rm -f /usr/local/nagios/var/ndo.sock
# rm -f /usr/local/nagios/var/ndo2db.lock
# rm -f /usr/local/nagiosxi/var/reconfigure_nagios.lock
# for i in `ipcs -q | grep nagios |awk '{print $2}'`; do ipcrm -q $i; done
# service ndo2db start
# service nagios start
# service mysqld start
# service crond start
# service httpd start
If that does not resolve the issue, can you PM me your Profile? You can download it by going to Admin > System Config > System Profile and click the ***Download Profile*** button towards the top. If for whatever reason you *cannot* download the profile, please put the output of View System Info (5.3.4+, Show Profile if older) in the thread (that will at least get us some info). This will give us access to many of the logs we would otherwise ask for individually. If security is a concern, you can unzip the profile take out what you like, and then zip it up again. We may end up needing something you remove, but we can ask for that specifically.
After you PM the profile, please update this thread. Updating this thread is the only way for it to show back up on our dashboard.