THIS IS A TEST INSTANCE. ALL YOUR CHANGES WILL BE LOST!!!!
What is Http Health Checking for?
- Http Health Checking is a Layer 7 health check method, it need make a special http request to the origin server, and check the result for good healthy, typically for http response code.
- why L7 health checking is required?
- maintenance requirement: now a days, most site have more than one origin servers for load balancing and service redundancy. but as servers is expect to have maintenance down times, there need a good way to pull down some server off service in a way that is easy to manage/change.
- service broken: when there is chance when L4 port is open but you can not get any http request handled.
- backend service broken: when your origin server using LAMP like system, and when your mysql down, you will sure get bad result. that is not what you want anyway.
What have been done in TS?
- L4 health checking:
- when failed in connection/reading/writing, it will trigger up the L4 fail function
- the failed host will be put into the ring to retry, after the failure timeouts
- L4 health status stored in hostdb
- hostdb information cluster sharing, when enabled
What we need to do in implement of L7 checking?
- TBD