FAQ

Check_MK

How can I receive absolute instead of relative time data?

Check_MK's status displays show all time data less than 24 hours old as relative values - eg. "16 hrs". You can change these to absolute time data by using the display options opened with the button at the top left of every window.

How can I query a dashboard without taking the intermediate step via the login page?

Dashboards cannot be queried with the Automation-User. It is however possible for a regular user by using a specially-constructed URL.

You basically open the login page with valid access data, and following the login, allow yourself to be redirected to the dashboard.

If the dashboard's URL is as follows: dashboard.py?name=my_custom_dashboard, you must first encode this URL. This can be performed with a number of online converters, for example, or on the command line with:

python -c 'import urllib ; print(urllib.quote("dashboard.py?name=my_custom_dashboard"))'

Then substitute your environment's appropriate values in place of the CAPITALISED placeholders in the following URL:

http://SERVER/SITE/check_mk/login.py?_username=USERNAME&_password=PASSWORD&_login=1&_origtarget=URL

An example of a URL could look like this:

http://monitoring/testsite/check_mk/login.py?_username=omdadmin&_password=omd&_login=1&_origtarget=dashboard.py%3Fname%3Dmy_custom_dashboard

This by the way also functions for other URLs, for example, NagVis-Maps. Instead of the dashboard-URL simply use the NagVis-Map's URL.

Check_MK Appliance

How can I clear the mail queue?

It might happen that there are several mails in the local queue on the appliance, which have been created due to a misconfiguration. In this case it might be useful to be able to clear the queue.

The mail queue can be deleted on the page _Manage email_ of the Web Configuration. On this page you can delete the emails one by one if you like.

Additionally, you can delete the emails using SSH. You need to enable root access via SSH and connect to the device as root user. After login you can execute the _mailq_ command to take a look at the mail queue and _rm /var/spool/nullmailer/queue/*_ to delete all mails from the queue.

Can the Check_MK virt1 be used with Citrix Xen?

Yes. You can directly import the OVA file we provide into your Citrix Xen Host.

Can the Check_MK virt1 be used with Microsoft Hyper-V?

It is possible, but not officially supported. However, it is possible to convert the OVA file we provide to a format which can be imported to your Hyper-V server.

Is it possible to access the appliance via SSH?

Yes, you can enable access of different users via SSH. You can find more details in the chapter Remote access via SSH.

Is a dedicated subscription needed for each device?

Not generally. For the subscription level the number of monitored services is relevant.

Where can I find the documentation for the appliance?

If you buy a device, you will receive a printed manual with your device. The up-to-date documentation can be found on our website in the User Manual or can be downloaded as PDF from the Appliance Downloads page.

Is the cluster active/passive or is it active/active?

The cluster of two devices is always an active/passive cluster where one device is holding all resources and the other is waiting for the other to fail to take over the resources.

Is it possible to create clusters of more than two devices?

No, the appliance cluster can only have two devices.

Is it possible to extend the RAM of the Check_MK rack1?

The Check_MK rack1 Mark I and Check_MK rack1 Mark II have 4 DIMM sockets for DDR3 RAM. Both can handle up to 32GB ECC unbuffered DDR3-1600MHz RAM.

The Check_MK rack4 Mark I has 16 DIMM sockets for DDR4 modules. The device can work with up to 1TB DDR4-2400 ECC RAM.

So technically it is possible to extend the RAM. You are allowed to exchange the built-in memory modules to extend the memory of the devices on your own.

Please ensure that you know what you are doing. We are not responsible for any damage done to the hardware.

Is it possible to configure the IP address via DHCP?

No, this is currently not possible.

Has the appliance support for VLANs (IEEE 802.1q)?

As of firmware version 1.3.5 is is possible to configure VLANs using the advanced network configuration.

Is it possible to extend the HDDs of the Check_MK rack?

The Check_MK rack1 Mark I has two 2.5" front mount slots.

The Check_MK rack1 Mark II has 4x 3.5" front mount slots. With the current firmware you can use the first two mount slots.

The Check_MK rack4 Mark I has 4x 3.5" front mount slots. With the current firmware you can use the first two mount slots.

You can use custom HDDs/SSDs instead of the delivered ones. The drives are always configured as RAID-1.

Can the Check_MK virt1 be used with KVM?

Yes. You basically need to download the OVA file we provide, unpack it and convert the shipped virtual HDDs from the VMDK format to e.g. the QCOW2 format. Then you can copy these virtual hard disk files to the paths your VM images are stored. And then create a VM with the parameters of your choice and use the just converted QCOW2 disk images as harddisks.

You may want to take a look at the "virt1.ovf" file to see which parameters to use for the VM you create in the next steps. Some things are mandatory:

  • You need to give the VM at least 2 GB of memory.
  • You need to use the BOTH hard disks you just converted.
  • Use virtio for the disks for best performance.
Subscription

How precisely are the subscription's services counted?

The number of productive monitored services is relevant for the necessary subscription level.. This number can be found at top left in the Check_MK interface's Tactical Overview. If it is the case that you operate Check_MK redundantly in an HA-cluster the services will not be doubly counted. Pure test systems for trialling Check_MK versions, etc., are also not counted. If multiple Check_MK instances are in use, then the sum of the services over all of the instances in your business is the relevent number. Standalone or single HA-Cluster: In your monitoring site, you can find under the host on which your site is running a service "OMD MYSITE performance", which has a graph tracking the number of monitored hosts and services. Alternatively, you can search for "OMD" in the quicksearch to find this service. The history of number of services has to be assumed by the graph "Check Performance" if the agent on the Check_MK server is older than version 1.2.8. Distributed Monitoring: The mentioned graph is available for every site. You can add these graphs to a shared custom graph to get the total number of services over all sites and then summarize these. Here is explained how summarizing works: Calculating with formulae on custom graphs

Am I permitted to operate the Check_MK Enterprise Edition on multiple servers?

Yes. You are completely free as to the number of Check_MK instances used for configuring your monitoring. Only the total number of monitored services is used to determine the subscription size.

Does the number of hosts being monitored influence the subscription price?

No. The price is determined solely by the total number of monitored services.

How many services must I take into account if I have X hosts to monitor?

For a typical processing centre you can expect to have around 30-70 services per host. But naturally it makes a difference if you, eg. monitor a switch only with PING, or a data base server with 50 Oracle instances.

What limitations does the demo version of Check_MK have?

The demo version of Check_MK is completely identical with the Enterprise Edition - except for the fact, that about 5% of the check results randomly get the state "WARN". That means that you can try out all of the features of the Enterprise Edition - event in a distributed setup. It's just not possible to use the demo version in a production environment. The demo version can be updated to a full version later - while your configuration and data is kept.

Which services count towards the subscription price if I run a combination of CEE and CRE?

All services that are visible on a CEE-site are counted.

Example 1: - Site1 CEE 2000 services - Site 2 CRE 1500 services - Independent sites that do not communicate with each other. => The subscription will be calculated based on the 2000 services on site1.

Example 2: The same sites as in example 1, but additionally the services on Site1 are via Multisite visible on Site2 => The subscription will be calculated based on the 2000 services on site1.

Example 3: The same sites as in example 1, but additionally the services on Site2 are via Multisite visible on Site1 => The subscription will be calculated based on the 2000 services on site1, plus the 1500 services on Site2 – making a total 3500 services.

When do I need a subscription with the option "Managed Services"?

When I monitor a physical system (hardware) whose functions are provided exclusively for another specific organisation (end customer).

Clarifications: * It is irrelevant whether the monitored systems used by the end customer are my property or the customer's. It is also irrelevant whether a system is located in my or in the customer's processing centre. * The monitoring of pure software services or virtual machines provided by the end customer does not require the MSP-Option. * The monitoring of hardware used by multiple end customers likewise does not require the MSP-Option.

When will my customer require their own Check_MK-Subscription?

When they use the Check_MK-System themselves. A Check_MK-system user is one who rectifies – or who initiates the rectification of – problems identified by Check_MK. Whether the Check_MK is installed on your server or on the end user's (customer's) is irrelevant. Your end user will require their own subscription when you install, configure and maintain the system for them. Your customer will not require their own subscription when they only receive PDF reports from Check_MK or have access purely for information, but they are not responsible for rectifying problems reported by Check_MK. Also your customer may manage scheduled downtimes and acknowledges with Check_MK.

Credits

Can I receive professional support for the Check_MK Raw Edition?

No. If you desire professional support for Check_MK, then you will need to take out a subscription for the Check_MK Enterprise Edition. Within the support framework, we will of course also be happy to assist you with a migration from the Raw Edition or from another monitoring solution to the Enterprise Edition. Exchanges regarding the Raw Edition can be found in the free Check_MK mailing lists.

For how long are credits valid?

Credits are valid for 12 months from the purchase date, after which time they expire. However, before the expiry date, you can submit requests for tasks to us to the value of your remaining credits. In such a case the credits will not expire, even if the actual execution of the tasks will take longer.

Trainings

At what times do the training courses start and finish?

All courses start at 10:00 a.m. on the the first day, and at 9:00 a.m. on subsequent days. Course days end at 5:00 p.m, except for the final day which ends at 4:00 p.m.

Community

We offer several mailing lists for Check_MK. Join them now to be updated at first hand.

Contact

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