load balancing % available

[benson9]

Hello,
I'm not yet an Nginx user, but have a question on it's capacbility.

I've had a look at the http load balancer, but cannot see anything that
would allow me to set the % or number of servers in an upstream backend
group that should be available before an error response is returned. 

The scenario I am looking into is one where Nginx can manage load balancing
across servers in a tier and there are multiple tiers. If less than 50%
servers are available in any tier I would like to respond with a HTTP
failure and the hardware load balancer can then route traffic to a standby
data centre.

If the status page returns information about all the servers in the group in
each tier then perhaps some orchestrating check called by the hardware load
balancer could detemine whether the site is considered available? 

Is an orchestrating check available in Nginx and can % available be set? 

I look forward to any responses.

Thanks
Benson

Posted at Nginx Forum: https://forum.nginx.org/read.php?2,266143,266143#msg-266143