Exegesis Windows servers are kept fully patched for security and performance. 

The Hyper-V core servers that host all virtualised application servers are set to check and apply updates at in the early hours of the morning (GMT). Sometimes these updates require a restart, typically taking 5 to 15 minutes as the virtual servers are saved and restored. The Hyper-V servers run Windows Core OS, which significantly restricts the number of updates required compared to a full copy of Windows Server, minimising the likelihood of a reboot.

In addition, each virtualised application server checks for updates (and may restart) on a weekly basis. Typically this is scheduled after midnight every Saturday or Sunday night. On a Virtual Private Server this can be adjusted to a customer's requirements. The restart will typically take a few minutes.

Microsoft security bulletins are released on the second Tuesday of each month.  This means that the period a server is “at risk” of a restart required by security updates is in the few days following that Tuesday (noting that updates and restarts will only occur in the early hours of the morning).  The installations of security updates are staggered across all virtualised servers, with the objective that all receive updates within a week of the Microsoft release.

Most virtualised servers are also equipped with anti-virus and anti-malware protection. These applications typically updates their definitions every day, without requiring restarts.

Other 3rd party and/or Exegesis applications, where installed on virtualised servers, will typically require their own maintenance plans, by arrangement between Exegesis and the customer.

Information on Microsoft updates can be found here:

https://support.microsoft.com/en-us/help/894199/software-update-services-and-windows-server-update-services-2019