Failed_to_pick_backend

[EJ Kowal]

Trying to install wordpress to google flexible environment, as documented here:

https://cloud.google.com/php/tutorials/wordpress-app-engine-flexible

I have it installed with not errors but am getting this error when I try to connect to the service:

Error: Server Error

The server encountered a temporary error and could not complete your request.

Please try again in 30 seconds.

Only error I can find is in cloud http load balancer and I am not sure the steps to take to fix this.

72.253.101.37 - "GET https://birdy-cages.appspot.com/" 502 451 "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/59.0.3071.47 Safari/537.36"

 

 

 

}

 

 

 

 

 

[Attila-Mihaly Balazs]

Hmmm, I'm no expert at this, but I think that the error message means that you're trying to use a Google Load Balancer (https://cloud.google.com/compute/docs/load-balancing/http/). However when using AppEngine, the load balancing is done automatically, you don't need to manually configure a load balancer (load balancers are only useful with Container Engine or similar services).

Regards,
Attila

[EJ Kowal]

Thank you I wound up checking the database connection and found it didn't have a connection. I think the error was saying that it was unable to find and instance that could handle the request considering both were not connecting to the database.

[Nicholas (Google Cloud Support)]

Hey EJ,

Your interpretation of the error is the most likely cause.  While one cannot necessarily see the Loud Balancer resource that is deployed alongside Flexible services, they are most certainly present and generate logs.  The logs can usually be viewed under Cloud HTTP Load Balancer as you no doubt have seen from the log entry you posted above.

The failed_to_pick_backend response can occur when the load balancer cannot find a healthy or available instance to which its request should be routed.  It may be a good idea when seeing such load balancer errors to consult instance usage and health checks to ensure these responses are correlated.