Citrix SCOM Management Packs by GripMatix
Saturday, 17 August 2019 23:05

SCOM Citrix Monitoring with MetrixInsight for CVAD – A Walkthrough

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MetrixInsight for CVAD is a System Center Operations Manager (SCOM) Management Pack bundle that enables SCOM to discover and monitor Citrix Virtual Apps and Desktops infrastructure components that form up your Citrix Virtual Apps and Desktops deployment. You can get a free trial here. Within SCOM these components are known as objects or instances. The solution discovers and monitors the following (highlighted) Citrix Virtual Apps and Desktop objects.

This blog describes what MetrixInsight for CVAD monitors for each object.

 

StoreFront Servers and StoreFront Stores

StoreFront acts as an enterprise application store that delivers applications and/or desktop resources from the Citrix Virtual Apps and Desktops environment to the user. A user authenticates via StoreFront to enumerate their resources. When a user clicks on one of their resources, an ICA file gets delivered from StoreFront that opens up with the Citrix Workspace App (formerly Citrix Receiver). The availability of StoreFront is crucial as it acts as the link between the user’s client and the Citrix resources hosted in the datacenter/cloud.

Therefore MetrixInsight for CVAD monitors the following objects of StoreFront:The availability of each StoreFront store by probing the discovery URL of that Store by using a web request.

  • The expiration date of the SSL certificates used by each StoreFront server.

  • The availability of the StoreFront windows services running on a StoreFront server including IIS.

  • By embedding the Windows Operating System management pack, the health and performance of the Operating System where the StoreFront role is hosted is also been monitored.

Citrix License Servers and License Server Licenses

The license server hosts and manages the licenses of the Citrix products you are eligible for. Products like Virtual Apps and Desktops, Provisioning, Workspace Environment Manager and others need a functional license server with valid and enough licenses in order to work properly. Therefore monitoring the availability of the license server and its licenses is important.

 

MetrixInsight for CVAD monitors the following objects of the Citrix License server:

  • The availability of the Citrix License server windows services running on a License server.

  • The number of licenses in use for each license loaded on a License server.

  • The percentage of licenses in use for each license loaded on a License server.

  • The number of licenses available for each license loaded on a License server.

  • The Subscription Advantage expire date for each license loaded on a License server.

By using these counters you stay in control of your license server availability and the utilization of your licenses during a given period in time.

 

CVAD Delivery Controllers

The delivery controller(s) are acting as the central managing and configuration hub within a Virtual Apps and Desktops site. Components like the hypervisor, StoreFront, Director and the VDA’s communicate directly with the Delivery Controller. They can be seen as the heart of the CVAD infrastructure cause without them the CVAD environment would be inaccessible to users and not managed and controlled.  The Delivery Controller(s) are responsible for hosting the Site configuration, managing and brokering users to their resources and perform power management against hypervisors and/or (cloud) hosting platforms.

Therefore monitoring the availability of the delivery controller(s) is important.

 

MetrixInsight for CVAD monitors the following objects of the Citrix Delivery Controller:

  • The availability of the Citrix Delivery Controller server windows services running on a Delivery Controller.

  • The health state of the broker service (e.g. is it not in a faulted state by means of configuration issues or problems with the site database).

  • The health of the license server from perspective of the delivery controller (e.g. is the license server reachable from the controller).

  • The license grace state of the delivery controller.

  • The availability of connectivity from the delivery controller to the site database.

  • By embedding the Windows Operating System management pack, the health and performance of the Operating System where the Delivery Controller role is hosted is also been monitored.

CVAD Sites

A Citrix Virtual Apps and Desktops Site is the highest logical object within a Citrix Virtual Apps and Desktop infrastructure. A site is hosted by one or more delivery controller(s), connected to a citrix license server and its configuration is stored within a SQL database, also known as the site database. A site can consist of multiple Zone’s, Machine Catalogs, VDA’s, Delivery Groups and Hosting Connection’s. Since the site is hosted by the delivery controller(s) and the database, the site availability is monitored on that level. However, at site level various performance data is essential to see what is going on within your Virtual Apps and Desktops environment. These data is therefore also kept for reporting purposes to be able to do trend analyses over time.

 

MetrixInsight for CVAD monitors the following objects on site level:

  • The maximum and average logon duration, since these are among the key metrics how well your environment performs for your users. For maximum logon duration the last collection interval is measured. For average logon duration, by default, the last 5.

  • The amount of concurrent sessions, this is the sum of connected and disconnected sessions that are active within the site, it gives you a clear picture of how the environment is utilized by users.

  • The amount of connected sessions, these are sessions that are active and actually connected, in general you can consider these kind of sessions actively being used by a user.

  • The amount of disconnected sessions, there are sessions that are active but not connected. This kind of sessions are interesting to monitor, because they are using system resources while they are not actively being used by a user.

CVAD Hosting Connections

Hosting connections are objects that exist within a site or a specific zone within that site.

Hosting connections or sometimes also called Hypervisor connections are the connections that the delivery controllers use to connect to a hosting resource. These hosting resources can be:

  • On-Premises hypervisors like VMware vSphere, Citrix XenServer, Microsoft Hyper-V (with SCVMM), Nutanix Acropolis.

  • Cloud platforms like Microsoft Azure, Amazon Web Services (AWS), Citrix CloudPlatform.

These connections are used for performing power management and provisioning tasks on the resources hosted by the hosting resource.
If these connections are not operating correctly, these task will fail causing resource availability problems.

MetrixInsight for CVAD monitors the following on hosting connection level:

  • The availability status of the hosting connection shows if the hosting connection is healthy or for instance in maintenance or a failed state. 

CVAD Machine Catalogs

Machine Catalogs are objects that exist within a site or a specific zone within that site.

Basically they are a collection of physical or virtual machines with the same type of server or desktop operating system, managed as a single entity. A Machine Catalog can be provisioned with either Machine Creation Services, Provisioning Services or another 3rd party provisioning mechanism.

Machines within a Machine Catalog can be assigned to a delivery group.

MetrixInsight for CVAD monitors if there are any machines not assigned to a delivery group and therefore not being used.

 

CVAD Delivery Groups

Delivery Groups are objects that exist within a site.

A Delivery Group is a collection of machines selected from one or more Machine Catalogs. The Delivery Group specifies which users can use those machines, plus the applications and/or desktops available to those users. Also power management and reboot schedules can be configured at delivery group level. Since the delivery group is bound to the user, monitoring availability, configuration and performance at delivery group level is essential.

 

MetrixInsight for CVAD monitors the following on delivery group level:

  • Monitors for failed desktop or server machines within the delivery group. Failures can vary from machines become stuck on boot or unexpected unregistered VDA’s that might be caused by infrastructure or operating system failures. Failed machines can seriously impact the user experience, which makes it a critical metric to monitor.

  • Monitors for delivery groups configured in maintenance mode. Maintenance mode is usually a temporary action performed by a administrator. However, if an administrators “forgot” to disable maintenance mode again, users could be impacted as their resources are not available for use.

  • Monitors for availability of desktops or servers available for brokering in a delivery group. You want to make sure your delivery group has still enough resource capacity for hosting new user sessions.

  • Monitors the maximum and average logon duration within a delivery group. As the logon duration is one of the key metrics for measuring performance of a VDI/SBC environment and impacts end user experience.

  • The amount of concurrent sessions, this is the sum of connected and disconnected sessions that are active within the delivery group, it gives you a clear picture of how the environment is utilized by users.

  • The amount of connected sessions, these are sessions that are active and actually connected, in general you can consider these kind of sessions actively being used by a user.

  • The amount of disconnected sessions, there are sessions that are active but not connected. This kind of sessions are interesting to monitor, because they are using system resources while they are not actively being used by a user.

  • Monitor for expired disconnected sessions. As a best practice to clean up unnecessary system resources being used, usually a disconnected timer is configured so that disconnected session gets logged off automatically. In practice those session might hang sometimes because a process is blocking a logoff action (e.g. a Microsoft Word document has been left open while not saved). This monitor triggers attention for the administrator to those sessions.

  • Monitor for Server OS machines within the delivery group where maximum capacity is reached based on the load index value. If this happens a lot, this could mean the environment maybe should scale up resources.

  • Monitor for failed user connections. User connections attempts might fail once in a while by various reasons( e.g. unstable connection). However if this happens for too much users within a time frame, this might mean there is something wrong.

CVAD Server OS Machines

Server OS Machines are objects that exist within a Machine Catalog.

A Server OS Machine is also commonly referred as a Session Host, Terminal Server, Remote Desktop Server, XenApp host and other(s). Basically it is a physical or virtual machine based on a Server OS with a Citrix VDA enabled that is configured to host multiple simultaneous user sessions. When using Server OS Machines in your environment, this means you are running a Server Based Computing (SBC) workload as multiple users share the same session hosts to run their applications and/or desktops.

 

MetrixInsight for CVAD monitors the following on Server OS Machine level:

  • Monitors the fault state. A Server OS machine can become in a fault state caused by different scenarios. For example it can have the fault state “unregistered”. This could mean a Server OS Machine experienced a unexpected shutdown, crashed or became unresponsive. As a Server OS Machine host multiple user sessions, you want to know if things happen at this level, because multiple user sessions can be affected by this.

  • Monitors the Load Index. Citrix is using a load index value to determine the actual load on a Server OS Machine. This load index is used for load balancing user connections. The load index is determined based on the various  factors like CPU usage percentage, Disk queue length , Memory usage percentage, Maximum number of sessions on a server and more. These factors and the behavior regarding determining the load index value can be configured by using Citrix policies.

  • The amount of concurrent sessions, this is the sum of connected and disconnected sessions that are active on the Server OS Machine, it gives you a clear picture of how the Server OS Machine is utilized by users.

  • The OS uptime of the Server OS Machine. In a Server Based Computing environment it is a common practice to reboot the resources once in a while to avoid performance-degradation for the end users. In general this is achieved by configuring reboot schedules during off working hours.

  • The PVS write cache size of the Server OS Machine when Provisioning Services is used as a provisioning method.

Provisioning Services Servers

A Provisioning services server is an object that exist within a Provisioning services site within a Provisioning services farm.

A provisioning services server is a physical or virtual windows machine hosting the Provisioning Services software that is responsible for streaming a virtual disk over the network to its provisioning services targets (e.g. Server OS Machines or Desktop OS machines when used within a SBC/VDI environment).

 

MetrixInsight for CVAD monitors the following on provisioning services server level:

  • The availability of the Provisioning Services server windows services running on a Provisioning Services server.

  • The status of the provision services server. A status is OK if the stream service is functioning and the SOAP service responds and can talk to the Provisioning Services database.

  • The amount of active target devices streamed from the provisioning server. If this amount is 0, that could indicate no targets are working or the load is not equally load balanced across your provision services servers for some reason.

Provisioning Services Stores

A Provisioning services Store is a location where the vDisks used to provision are stored. This is typically local disk storage on the Provisioning Services server, or a SMB share hosted on a High Available storage solution.

MetrixInsight for CVAD monitors the following on provisioning services store level:

  • The amount of free space left on the vDisk store. Enough space should be available for hosting vDisks and/or their write caches.

Provisioning Services vDisks

A Provisioning services vDisk is an object that exist within a Provisioning services site within a Provisioning services farm.

The vDisk is a VHD(X) based file that contains the Operating System and its application streamed to a target device over the network. The configuration and availability of a vDisk have high impact on the user experience and therefore should be monitored.

 

MetrixInsight for CVAD monitors the following on vDisk level:

  • Cache type of the vDisk. For read-only vDisks there are multiple cache configuration options. However, in general there are only two options that can be considered as best-practice regarding vDisk performance. This monitor checks the configuration of the vDisk cache.

  • Load balancing of the vDisk. The provisioned vDisk can be load-balanced over multiple provision services servers. This monitor will check if load balancing is active on the vDisk.

  • Replication status of the vDisk. When using multiple vDisk store locations, the vDisk need to be replicated to those location. If not, a single point of failure may be created, which you want to avoid in general. This monitor checks if the vDisk is replicated and available on all locations in the Store.

 

This management pack bundle also provides reporting functionality and will be covered in a next blog post.
Stay tuned!

 

At GripMatix, we believe in no-nonsense tooling to help IT departments leveraging the quality of their infrastructure.