Is there a solution/service available on GCP in similar lines of Systems Manager? My end goal is to run a shell script on GCP VM on specific events.
Like for AWS, via EventBridge I was able to trigger a Lambda Function and the function in turn triggered a SSM command for specific VM.
Is this possible on GCP?
There isn't a Systems Manager equivalent in GCP.
A Pub/Sub subscription from the VMs/compute units which triggers a lambda function (cloud function in GCP) is a suboptimal solution and different from what Systems Manager accomplishes..
I don't know what kind of events you have in mind that would trigger running a script but you can check out the tutorial how to run a function using pub/sub. It shows how to use scheduler based events but it's possible to use not-scheduled triggers;
Events are things that happen within your cloud environment that you might want to take action on. These might be changes to data in a database, files added to a storage system, or a new virtual machine instance being created. Currently, Cloud Functions supports events from the following providers:
HTTP Cloud Storage Cloud Pub/Sub Cloud Firestore Firebase (Realtime Database, Storage, Analytics, Auth) Stackdriver Logging—forward log entries to a Pub/Sub topic by creating a sink. You can then trigger the function.
And here you can read on how to implement those triggers.
For example this documentation explains how to use storage based triggers in pub/sub.
If you provide more details of what exactly you want to achieve (what events have to trigger what) then I can point you to a more direct solution.
The approach depends on the exact use case you have in hand. One of the common architecture option could be using pub/sub with cloud functions. Based on messages published to Pub/Sub topics, cloud functions performing operations of our interest can be triggered/ invoked in the same cloud project as the function.
