Purpose
The purpose of this exercise is to create snapshots of your instance as backups and use these snapshots to create additional instances.
A snapshot is a GCP object that contains the files from a disk. Don’t confuse this with screenshot, which is a image you use to document some activity in the exercise.
Preparation
Read
Creating Persistent Disk SnapshotsLinks to an external site.
to get an idea of the process. You use snapshots as a way of backing up disks used by your instances.
Assignment
Create a Word document that contains your screenshots and explanations of what you are doing.
Create a new instance called unit7-base (f1-micro, standard persistent disk, allow http traffic), then install nginx and add your name and unit 7 to the index page.
Shut down your instance
Create a snapshot.
Start your instance, install php, test your instance to be sure it runs info.php.
Shut down your instance
Create another snapshot.
Start your instance, install a prebuilt php web site (see below). Test your website. Take a screenshot showing the home page of the simple php website and the URL (ip address) you used to access the page.
Then shut down your instance.
Create a third snapshot. When it is finished, take a screenshot showing all three snapshots and their sizes.
At this point, you have three snapshots, one for each stage of the installation process. Now it is time to create instances using these snapshots. See
https://cloud.google.com/compute/docs/instances/create-start-instance#createsnapshotLinks to an external site.
for information on this process.
Create a new instance named unit7-copy. Instead of creating it with a new disk, use your latest snapshot instead.
Test your new instance. When you click on the External IP link and specify the new port number, you should see a web site that behaves exactly like the one you built originally. Take a screenshot of your simple php web site, showing your IP address and the home page.
Take a screenshot of your current snapshots
Snapshots taken at regular intervals (daily, weekly, hourly) or after major changes, like adding new software, provide backups of your work which can be used to create new instances in the future.
At the end of your Word document, include the answers to the following questions:
Why are the snapshots of the same disk dramatically different sizes and why do they seem to get smaller even after adding software to the system?
Describe how you got the simple website files onto your instance.
In a sentence or two, what did you learn?
In a sentence or two, what did you like about this project?
In a sentence or two, what did you find confusing or would like to see done differently regarding this project?
