Maintenance windows that require change control board approval for Azure Stack HCI updates must consider the total attended and unattended time. Typically, organizations require maintenance windows during LCM operations because update failures have the potential to affect the normal response times that end users experience. On the four-node cluster in the lab, the benefit of the automated approach meant a 40 percent shorter maintenance window as compared with the manual approach.
In our lab testing of the automated process, each node beyond the first node took 45 minutes in total—including both unattended and attended time—to complete the update. (The first node took a little longer due to preparation tasks.) Using the manual process, each node beyond the first node took about 71 minutes total time to complete.
The following figure compares the total maintenance windows for automated and manual updates:
Figure 6. Maintenance window: Automated and manual approach comparison
To put this time savings into perspective, consider the time consumed by LCM tasks within large enterprise IT organizations. Some enterprises use Azure Stack HCI to solve their business challenges in globally distributed remote branch offices and regional data centers. The challenges presented by LCM activities increase exponentially with multiple clusters. Dell Technologies releases quarterly updates for Dell EMC Solutions for Microsoft Azure Stack HCI and recommends applying the updates as soon as possible. Based on the lab testing, an IT organization that must update 20 four-node clusters each quarter could expect to save almost an entire week of time per year by following the automated approach instead of the manual approach.