FAQ Category Check_MK Appliance
#0008 - 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.
#0009 - 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.
#0010 - 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.
#0011 - 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.
#0012 - Is a dedicated subscription needed for each device?
Not generally. For the subscription level the number of monitored services is relevant.
#0013 - 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.
#0014 - 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.
#0015 - Is it possible to create clusters of more than two devices?
No, the appliance cluster can only have two devices.
#0017 - 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.
#0018 - Is it possible to configure the IP address via DHCP?
No, this is currently not possible.
#0019 - 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.
#0021 - 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.
#0026 - 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: