Q: What will happen if Instana backend URL will change? How the application will behave? Can we test the behavior just by changing the URL for the incorrect one?
A: Nothing will happen. The reporting will just fail. reported beacons will still be in the local queue until it is full
Q: How the application will behave if the Instana backend will return an error? How we can test it?
A: The same as above.
Q: How the application will behave if the Instana backend will respond with delay? Will it cause DDOS of Instana backend from all end clients' mobile apps? How we can test it?
A: if there is a delay but the request is successful. everything is fine. No error will be shown.
If the customer is worried about the agent using too many resources in the device to send beacons (making the app slower), or the apps sending so much info to the server that the server chokes:
- when the agent tracks a request, a beacon is saved in the device's filesystem (about 600byte per beacon)
- the agents wait until the app has not used the network for a few seconds, in order to make sure the app's "normal" network usage always has priority. Then, the agent creates batches of beacons and sends them to the server (gzipped, if the device supports it)
- if for some reason the agent can't send beacons to the server (connection error, gateway issues, DNS issues,...), the agent will retry later.