The update that broke the printers
On Monday, an update goes to all 300 PCs. By lunchtime, nobody can print. The technician must undo it, on 300 PCs, fast.
A team that planned a way back finishes in an hour. A team that did not may take a week.
Key words
| Word | What it means |
|---|---|
| Operating system | the program that runs a computer and its other programs |
| Driver | a small program that lets the system use a piece of hardware |
| Rollback | undoing an update to return to the version that worked |
| Release control | deciding which updates go out, to whom, and when |
| Group policy | a way to apply settings and software to many computers from one place |
| Test group | a few PCs that get an update first |
| Locally installed | put on a PC by hand or from the PC itself |
| Network deployed | sent to many PCs from a central server |
| Hold | to stop a program being updated |
| Known good | a version that is tested and works |
The cells students fill in are left blank in this preview.
By the end of this lesson
Note
I can explain how to roll back drivers, system updates and other updates, and how to control a release.
Starter
Have a go
Starter
3 questionsYour answers are marked here and are not kept. A college account keeps every student’s marks.
Installing updates safely
Install updates, but not blindly. Back up first. Read what the update changes. Try it on a test group. Then release it more widely.
Always plan the way back before you go forward. That way back is a rollback.
Rollback procedures
There are three kinds. Roll back a device driver. If a new driver breaks a device, return to the old driver version. Roll back an operating system update. If an update stops the system working, remove it, or use a restore point. Roll back an update. If a program update breaks a program, put the old version back.
Keep the old versions. Without them there is nothing to go back to.
Save a setting as the known good
printf 'timeout=30\n' > app.conf && cp app.conf app.conf.v1 && cat app.confA command for the lesson’s lab terminal. It is shown here and not run.
The update changes it
printf 'timeout=3\n' > app.conf && cat app.confA command for the lesson’s lab terminal. It is shown here and not run.
Roll back to the known good
cp app.conf.v1 app.conf && cat app.confA command for the lesson’s lab terminal. It is shown here and not run.