Nagios Support Forum

I have Nagios XI running on VMware Linux CentOS release 5.4 (Kernel 2.6.18-164.9.1.e15 on an i686)
I installed it from VMware image downloaded from Nagios download site.
It is running Nagios XI 2011R1.5.
The host OS is Windows 7.
I am using FireFox browser.

I have been experiencing an intermittent problem that I could not login to NagiosXI for a while and then received a burst of alert emails that hosts are DOWN and then RECOVERED.
It seems like that NMS became loaded somehow to the point that NagiosXI is not able to handle the loggin.
Also, during such interval, all host checks failed and generated CRITICAL alert emails.

I tried to login continuously when the problem occurred and logged in right after the condition is cleared.
Attached is the screen shot of NagiosXI home page right after I logged in.
It shows the red bar on 1-minute Load and I/O Wait CPU state.

What are possible causes and how to fix (or prevent) the problem?

Looking at your screenshot, we may be running into a resources problem.

Can you verify that your virtual machine is meeting these requirements
http://assets.nagios.com/downloads/nagi ... quirements

The system spec of the PC that NagiosXI is running on meets the minimum requirements specified in the link you have provided:
http://assets.nagios.com/downloads/nagi ... quirements

However, VM-CentOS version of NagiosXI was downloaded from Nagios site and the memory size of VM was set to 512M and Hard Disk size is set to 8GB.
These default settings of 512 M RAM and 8GB of Hard Disk meet only the minimum end of the system requirements.
How can I increase RAM and Hard Disk for VM-CentOS?
I have more RAM and Hard Disk on my PC which can be allocated to VM-CentOS.

You should can change the settings in the VMware Player or VMware Workstation whichever you are using.

In VMware Player
With the VM powered off, Right click on your VM and select "Virtual machine settings..."

In VMware Workstation
With the VM powered off, Right click on your VM and select "Settings"

Then you can adjust memory, and if needed, under the Hard Drive menu you can expand the drive in the utilities drop-down.

Take a look at your performance graphs for your localhost CPU load. Here are some tips for performance tuning as well.
http://assets.nagios.com/downloads/nagi ... p#boosting

Thanks very much.
I had been trying to increase them without powering down the VM Player.
Your instruction to increase Memory and HD Space is very useful.
Now, I finished increasing Memory and HD Space successfully.
I will try the RAM Disk and other tips to increase the performance.

Sounds good! Let us know if you have any more questions.