How is a salesforce site switch different from an instance refresh ? What is difference in terms of key things we need to check so that they do not impact adversely ?
A site switch is used by Salesforce mostly for maintenance and data recovery purposes. This Site Switching Overview knowledge article defines what is a site switch. In case of site switch, you do not lose any of your sandbox metadata or data, Users are just redirected seamlessly to another location without them being aware of behind the scenes activities. You though need to take certain actions to make sure this activity is seamless.
To get more details for faq and actions required for a site switch, refer the knowledge article which details out the topic.
Each Salesforce instance is built and maintained in two geographically separate locations. An instance is actively served from one location (the active site) with transactions replicating in near real-time to the other completely redundant location (the ready site). This infrastructure model allows us to switch the location of the active site for maintenance, compliance, and disaster recovery purposes, which is referred to as a site switch.
An instance refresh completely copies the metadata contents from Production (and data depending on type of sandbox) overriding any contents available in that sandbox. It's just like creating a new sandbox from Production and you lose any unsaved changes in that sandbox.
Refreshing a sandbox updates the sandbox’s metadata from its source org. If the sandbox is a clone or if it uses a sandbox template, the refresh process updates the org’s data in addition to its metadata.
One example where a site switch can affect you occurred to our org recently.
- We went from na30 to na81
Our middleware platform, Boomi, uses hard-coded instance names when you use the Boomi Platform Events feature. That is, Boomi was configured to use
https://na30.salesforce.com/... and we had to manually change this to the new