The Doppler Quarterly Summer 2018 - Page 72

Detailed Wave Schedule Rules Now that we have the initial migration wave plan, we still need to create a migration execution plan that lays out activities per day. As we already have the list of applications and the desired wave, it is now a matter of laying out these apps on a calendar. We used the following rules for creating the detailed schedule: Rule 1 – For every application, the migration sequencing must follow: first, Dev; next, other non production environments; finally, the production environment. Rule 2 – For every environment of an application, add into the schedule a gap of one week before the next environment is migrated. This allows for rollback, additional time for testing and adjusting migration procedures. Based on the velocity of migrations, it may not be possible to fit all applications within a wave, and further adjustment may be necessary, including moving apps to the next wave or to the backlog. This concludes the wave planning exercise. Realistically, for every wave, there is a preparation phase (of at least one prior wave), where there may be a need to fine tune the process. With situations where a rollback is required, applica- tions may have to be put in a backlog if they do not fit anywhere else in the cur- rent period/schedule. Figure 2 displays an example of a detailed wave schedule (partial view). WAVE 6 App-X App-X App-X App-X App-X App-X App-X App-X App-X App-X App-X App-X App-X App-X App-X App-X App-X App-X App-X App-X App-X App-X App-X App-X App-X App-X App-X TOTAL ENV’s Per Day 97 2 2 1 1 1 1 1 1 2 2 2 1 1 1 1 1 1 1 13 7 10 11 14 11 4 2 2 9/19 6 6 6 6 6 6 6 6 6 6 6 6 6 6 6 6 6 6 6 6 6 6 6 6 6 6 6 2 1 2 1 1 2 1 0 1 2 1 1 2 1 1 2 1 1 1 1 1 1 2 1 1 1 1 9/20 9/21 9/22 9/23 9/24 9/25 9/26 9/27 9/28 9/30 10/1 DEV QUAL DEV QUAL DEV DEV QUAL Client Time Off QUAL DEV QUAL DEV DEV DEV 2 2 2 0 0 QUAL 2 2 2 2 Figure 2: Detailed Wave Schedule (partial view) 70 | THE DOPPLER | SUMMER 2018 9/29 10/2 DEV 1 0 0 2 DEV DEV