Any system has a life, the campus dormitory WiFi billing system runs for three or five years, the bottom frame is old, the vendor doesn't maintain it, new needs are not met, and the change of time is on the schedule.——It's 24 hours a day, and it's still working at night. Once the whole school is offline for days, the complaint can be searched directly. So the core of the idea of changing is not."Can we change?"But..."Why not?"。
Think about it first: whether it's a whole replacement or smooth evolution.
One is to take root and change one with a new function but a concentrated risk; the other is to keep the architecture, submodule evolution, such as the first-infost authentication layer, then the next billing layer. The former is not working for the old system, the latter is breathing but partly backward. For this highly sensitive setting of dormitories, we tend to smooth out the evolution.——Breaking down the grid into a number of small switchings, each with a manageable impact. Of course, this requires that old and new systems coexist for some time, with early leeway in their design.
Data migration is the easiest part to roll over.
Accounts, billing records, equipment bindings, balances, historical data moved from the old system to the new one, which is the most dangerous part of a replacement. If you leave an account out, the student will not be able to access the net; the balance is not correct and the financials are blown first. The right thing is to do full-scale export and verification, then small pilot migration, and then to compare it with the rest of the business."AutoMove"Let go, you have to check your own data for money and account numbers.
Pick the low peak window and set a notice period for students.
Even if you want to cut, pick the least painful time. Final exams, leave eve, or a Friday night are relatively secure windows. But more important than the timing of the election is the announcement: one week ahead of the system's front page, public number, dormitory, and clear what time it takes, what impact it has, how it can be verified."I don't know why I suddenly broke the net."There is a short interruption in the announcement, and there is much more tolerance.
Keep the exit route. Don't block it.
A more elaborate plan could also turn the car around.——Even if it's a read-only mode, you can top it up and make basic authentication available."- It's a new one."The old environment was cleared, and the new system was exposed to major deficiencies, while students were largely out of reach without rescue. Retrenchment is not a sign of weakness, but of specialization. The demand phase should state how long the old version will be kept online, under what conditions, and who will approve it. This lifeline can't be saved.
Grayscale. One building, one building.
The surest strategy for the replacement is greyscale: pick a building to make a new system, run for two weeks, and expand to a few, with full amounts. Even if there are problems, it will affect only a small group of people, and positioning and restoring them quickly. And while the grayscales exist, they can directly compare experience and data and give confidence to decision makers. A school-wide staggering is basically about luck in the dormitory network.
The sign of the end of the replacement is"No one's aware of it."No, it's not."Switch complete"
Change old system disposal after completion, no tails left.
The new system can not be deleted immediately after it has passed the trial period and confirmed that no one is aware of any connection. It must be kept back-to-back, due to a formal downlink, and then released in full at the bottom line for audit and retroactive purposes. The sensitive data of account numbers, bill history, and the downline of old libraries are subject to school data disposal norms, and cannot be formatted with hands.
The other one's only looking at technology, and thinking about the transition.
The system changes. The people who use it have to follow it. The IPO has to retrain the new backstage, the new processor, the first line of processing work, and even the students have to be aware of the new interface. The technology is smooth and the switch is not followed."The new system is online, the old problem is still on."It's a bit awkward. It's suggested that we have a separate paragraph in the replacement plan."Transition of personnel": Train who, when and what standards. Taking people into the range of substitutions, this upgrade is complete, not just a bunch of equipment.
And finally, a mind. The criterion for success is not an announcement at dawn."The new system's online."The next week, students were supposed to brush the playbooks, play games, and almost no one noticed a change of system behind them. If the change made the whole school known, complained about it, it would explain how it was done.——The old quiet-silent exit, the new quietly connected to all the connections. Schools that do this often think about the data, windows, retreats, greyscales.