Search before asking

• I had searched in the issues and found no similar feature requirement.

Description

• Currently we don't have any metrics in alert server. If alert server fails, with metrics, it would be easier to track down the issues.
• Furthermore, metrics enable users to monitor alert server from external system and decrease the probability of failure.
• related: [Feature][Alert] Alarm availability improvement #10211

Are you willing to submit a PR?

• Yes I am willing to submit a PR!

Code of Conduct

• I agree to follow this project's Code of Conduct