Virtual environments in enterprises
Server virtualization is already part of everyday life in most companies in order to better allocate hardware resources. IT admins find it much easier to manage IT environments if they can at least partially virtualize servers. This increases the requirements for monitoring, since the virtualization platform, the underlying infrastructure, and the virtual machines (VMs) provide different information bases, which the IT team must collect and put in the correct context.
In addition to classic virtualization via hypervisors, more and more companies are using containers and platforms such as Kubernetes. When monitoring containers, there are some similarities to the monitoring of virtual servers, but there are also additional aspects that you should consider.
In any case, all-round visibility is essential for correct monitoring. Monitoring the individual containers or the hypervisior and the VMs alone is not sufficient. In addition to the infrastructure, companies must also consider network components, storage and other related elements in their monitoring. At the same time, monitoring must not lead to overloading IT admins and developers with manual processes.
Checkmk offers several tools to facilitate the creation and enforcement of specifications for individual servers, specific server types or entire clusters.
Virtualization aims to make you more dynamic: Whether you choose VMware vSphere, Microsoft Hyper-V, Citrix XenDesktop or another platform, it is likely that IT managers will no longer want to create hosts manually – instead hosts are created and decay automatically. Automation is important and also plays an important role in monitoring containers and their orchestration platforms. With Checkmk you can easily monitor Docker, Kubernetes and OpenShift.
Checkmk offers features like Dynamic Configuration Daemon (DCD), which makes manual maintenance of hosts unnecessary. As an all-in-one platform, Checkmk also offers a precise insight into all relevant areas: starting with the basic hardware or cloud infrastructure, the virtualization platform and the VMs themselves, right through to storage and network devices. You gain relevant insights in each area and can pinpoint errors precisely.
Advantages of monitoring virtualized servers with Checkmk
Extensive experience, and existing integrations
Checkmk offers over 1,900 integrations, including with VMware, CitrixXen and Microsoft Hyper-V.
Comprehensive environmental monitoring
As an all-in-one platform, Checkmk not only monitors virtual machines and hypervisors, but also all connected assets such as switches or storage.
Automatic host configuration
Thanks to the Dynamic Configuration Daemon, Checkmk is ideal for monitoring dynamic environments.
Easy creation of specific rules
Checkmk offers a powerful API with which you can automate host creation and integrate your own auxiliary tools.
Meeting challenges in the daily routine
Decoupling the hardware from individual subsystems makes it more difficult to identify the causes of problems. With virtualized servers in particular, the cause of complications is not always the same as the location of the impact. The solution to a problem is then not immediately recognizable. Incorrect monitoring literally floods IT teams with imprecise alarms or even false positives. Therefore, the context of server virtualization warnings is particularly important.
In addition, VMs are usually not set up centrally, but instead separately by more than one person. An IT monitoring solution must map the real circumstances in companies. In the worst case, VMs are not transferred to monitoring and are simply overlooked. Even if departments do not create machines themselves, they often use their own tools to check their areas, so that information is left out and processes are inefficient in removing alarms.
In practice, there are technical and organizational links. Therefore, monitoring must not act as an isolated solution, but must be able to easily integrate and map different information sources. At the same time, depending on the position of the user, there are different requirements for the level of detail and security clearance of the information. The administrator should be able to fine-tune the presentation of the monitoring data and the dashboards to different user groups.
Checkmk is not only able to collect all information, but you can individually adapt views to different user groups. Through integrated graphing-, dashboarding- and reporting engines, users without monitoring experience gain useful knowledge about possible sources of danger. You also have the option of expanding or limiting access rights depending on the purpose.
More than just VM monitoring: correctly identify relationships
Companies must of course keep an eye on basic areas such as CPU, RAM, partitions and network data as with every server, but virtualized environments have their own requirements due to their architecture. This includes, for example, checking the VMs for their heartbeat, taking snapshots and installing maintenance tools, but there are also even more specific details.
For example, VMs only see the storage actually used on a connected storage, and reserve this storage space for their own applications. The VM would only send an alarm if the used memory on the storage was so large that a reservation would no longer be possible. However, the VM only has its own applications in mind.
Checkmk is a phenomenal monitoring program that is constantly improving while remaining flexible enough for customizing to perfectly fit your unique monitoring needs.
The storage itself recognizes the size of the virtual hard disk and possibly its maximum size. It can’t anticipate an approaching peak in performance from several VMs. It is therefore important to consider the interactions of multiple VMs when accessing the same storage. Reservations should never exceed the available space.
Interpreting network and hypervisor information correctly
The information from the hypervisor is also important in many cases and always belongs to the monitoring. A hypervisor sees the real size of the virtual disks and the maximum size of the disks of its VMs. He also knows the real size of hard drives that are managed by other hypervisors. The hypervisor management platform (e.g. VMware vCenter) can determine the real and maximum size of all virtual hard disks on all hypervisors.
An example of the importance of data from the hypervisor is monitoring the interaction of VMs and networks. VMs, switches and storage are often connected redundantly. The VMs do not know the redundancies because they do not know where the hard disks are, or to which physical network interfaces the virtual interface of the VM is connected. However, the hypervisor knows about the redundancies when connecting to the storage or the network because it manages the (virtual) interfaces.
With Checkmk you can map possible scenarios precisely in the monitoring, and receive all data in a uniform platform. In addition to integrations with hypervisors and their management platforms, Checkmk supports interfaces from all leading manufacturers in the area of network devices, storage and servers. You can precisely localize alarms and target them.
Monitoring of virtualization platforms
The exact type of monitoring of virtualized servers depends on the platform used. Checkmk provides platforms such as VMware special agents. For other environments such as Microsoft Hyper-V or Citrix XenServer the agents for Windows or Linux are suitable.
VMware vSphere is a good example that illustrates the development of platforms and Checkmk. Checkmk has been able to use VMware’s interfaces for a long time, but older versions could still be monitored using the Linux agent from Checkmk.
The best way to monitor ESXi nodes is through the VMware API. On the one hand, the performance is better, on the other hand, IT admins benefit from additional features. This enables a better overview and allows automatic host configuration via the Dynamic Configuration Daemon (DCD) from Checkmk.
Checkmk retrieves the information from the vSphere API with a special agent; a user account with read access is sufficient on the VMware ESXi server. Implementation takes less than five minutes and you will have all VMs as services in Checkmk. If you also create the VMs as hosts in Checkmk, they are automatically supplied with the data from VMware vCenter. At VMware, the ESXi hypervisor comes as its own bare metal server, which you can also monitor with Checkmk.
Dynamic configuration of hosts with the DCD
In Checkmk, the Dynamic Configuration Daemon (DCD) enables you to automatically add and remove hosts based on monitoring information. In practice, this not only means little manual work is needed, but also it provides an exact traceability when creating and closing VMs – and also across teams if desired.
Checkmk can automatically take over and remove monitoring from AWS, Azure, Kubernetes, VMware and other sources via the DCD hosts. The ability of dynamic host configuration is aimed at users of the Checkmk Enterprise Edition and informs admins, for example, about VMs if idle or if incorrectly configured, but also deleted, modified or newly created hosts from other users.
Checkmk makes monitoring very easy and is so scalable that the size of the environment does not matter.
We are also working on deepening integrations. For this purpose, the DCD has been purposely designed as a platform, which in the future will be expanded by additional connectors with new functions. Each connector can collect information from a specific source and has its own specific configuration.
Checkmk agents in virtualized environments
In certain cases it makes sense to monitor virtualization environments using normal Checkmk agents, for example with Citrix XenDesktop. Management runs here via a Windows VM. Checkmk also supports the Citrix API. The XenServer itself is based on Linux and it can also be monitored with the appropriate Checkmk agent.
In the case of Microsoft Hyper-V, Checkmk benefits from its experience in Windows monitoring and the good integration into the Windows ecosystem. With the Windows agent, you canmonitor Hyper-V itself as well as virtualized clients and servers.
Checkmk continues to develop its integrations, and adapts to new possibilities. Companies can switch freely between manufacturers and platforms, or use them in parallel. Checkmk already has integrations with VMware, CitrixXen and Microsoft Hyper-V, and we are constantly expanding our capabilities and adapting to platform updates.
At the same time, you are flexible with server migration: Checkmk also monitors on-premises servers and integrates directly with manufacturer interfaces and IPMI. In addition, integrations with cloud providers such as Microsoft Azure and AWS are available.
Special functions for monitoring virtualized servers
Many organizations have been using Checkmk to monitor their virtual assets for years. Together with our community, we have therefore continued to develop and adapt monitoring. This know-how is immediately available to make monitoring of virtualized environments as accurate as possible.
For example, you can monitor snapshots precisely. These affect the performance of the VM. Snapshots should therefore only be used for a short time and deleted after creating a backup. As a comprehensive monitoring platform, Checkmk also integrates into tools such as Veeam in order to also keep an eye on the age of backups and initiate appropriate processes here if necessary. You can also be sure that the backup jobs have actually run.
In addition, special requirements can be easily met using Checkmk’s rule-based monitoring. For example, IT teams should set minimum storage space requirements for VMware ESXi more stringently than for normal servers. Because, if a node fails, VMware automatically migrates the affected VMs to the remaining nodes. However, these must then provide the necessary memory until the failed node is available again.
Depending on the size of the environment, the monitoring must therefore send alerts earlier in order to be able to compensate for a possible failure and to keep sufficient memory available. One approach, for example, would be 60 percent for four nodes of the same size, instead of setting the status to CRIT when the memory utilization was only 90 percent. Then three remaining nodes can compensate for a failure, or you receive an alert.
DevOps and IT Operations: Monitoring containers
Containers allow developers to create, test and migrate software faster. In recent years, companies have increasingly used Docker, Kubernetes and other tools. Virtualized applications, microservices and similar approaches must also be part of a surveillance strategy.
The technical challenge is that containers often only exist for a few minutes or even seconds, and developers often don’t have time to integrate them into a comprehensive monitoring. They also focus heavily on performance metrics and do not consider the condition of the underlying hardware or individual services.
The monitoring of the classic infrastructure is still the responsibility of the IT operation teams, but without a suitable basis they can have only fragmentary information. Coordination with the developers is complex and information silos can be quickly created. If there are problems between virtual systems and physical IT assets, this becomes a bottleneck because the teams have to exchange individual notes manually.
Agile methods in software development or approaches such as DevOps are only successful if companies adapt their monitoring accordingly, and find cross-team solutions for developers and IT operations. Monitoring Docker, Kubernetes or OpenShift provides important metrics and detailed information about the individual hosts, but depending on the user, monitoring tools must be specifically adaptable so that employees can work efficiently.
Checkmk recognizes containers and automatically integrates them into the monitoring. You can set very short measuring intervals to record short-lived containers, and also to remove containers from the monitoring automatically. Checkmk also integrates with Prometheus and enables efficient collaboration between developers and IT admins.
DevOps engineers and developers can use the data obtained to optimize software and processes. Checkmk integrates with Grafana to create meaningful graphics and it can store the information indefinitely. In this way you can use the insights gained for new projects.
I really like that almost everything in the software can be customized. I can create checks for my self-written apps, or monitor unusual use cases.
Frequently asked questions about monitoring virtual servers
Does it make a difference for monitoring wether my virtual servers are publicly accessible or if I want to use them as a single tenant server?
Such differences can be addressed in monitoring, but you don’t have to. Checkmk offers functions, for example, to send alerts when unknown IP addresses are accessed.
I have to migrate my server to a new host. How long does it take to adjust the monitoring?
The effort required is relatively low because Checkmk can obtain the information directly from the virtualization platform. If the host is in a different network, the Checkmk instance must be running there, but it can be easily managed via Distributed Monitoring function.
Do I have to do anything special with the firewall rules for virtualized servers?
No, adjustments are not necessary. If you use Windows systems on the virtual servers and monitor these via the Windows agent, an exception rule required for the Windows firewall may be required, but this is not related to virtualization.
I wnat to move my servers form my own data center to the cloud. Does Checkmk support cloud servers?
Yes, Checkmk is predestined for hybrid environments, and it can monitor servers of all kinds efficiently.