Enabling Audit Logs for IAM user and Service Account

Select your Google cloud project
Go to identity and access management service
Go to audit logs
By default all audit logs are enabled for admin rights related actions
You can select a service then you can also enable other action logging like admin reads, data read or data right actions
You can enable these logs for individual services or you can select all the services all at once and then you can enable logging for different actions
The audit logs are written to cloud operations logging

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