"invalid-pool-load-balancing-algorithm" logs on gorouter stdout

Products

• VMware Tanzu Application Service

Issue/Introduction

We see lot of "invalid-pool-load-balancing-algorithm" logs on gorouter stdout after upgrade from 4.10 to 6.10

{"log_level":3,"timestamp":"2025-01-26T06:15:26.767841464Z","message":"invalid-pool-load-balancing-algorithm","source":"vcap.gorouter","data":{"poolLBAlgorithm":""}

 

Environment

TAS 6.10

Cause

• We see GitHub issue for this issue.
  
  
• SurgicalPool has no load balancing algorithm leading to "invalid-pool-load-balancing-algorithm" error

         https://github.com/cloudfoundry/gorouter/issues/458

• Also tried running the command in the GitHub and able to get the below error.

curl -v "https://example-app.com/" -H "x-cf-app-instance: app_id:instance_id"

 

• The output is invalid header

{"log_level":3,"timestamp":"2025-03-24T06:16:37.005434627Z","message":"invalid-app-instance-header","source":"vcap.gorouter","data":

{"trace-id":"899ta9a6g54324147c6538970b1ef474","span-id":"876897520b1ef567","error":"Incorrect X-CF-APP-INSTANCE header : app_id:54a0d566-c7ce-42r2-8a4z-598d77d0c6e9"}

,"stack_trace":"code.cloudfoundry.org/gorouter/handlers.

       But the correct one is as below.

curl -v "https://example-app.com/" -H "x-cf-app-instance: app_id:app_index"

     
      Above command reproduces the invalid-pool log:    

{"log_level":3,"timestamp":"2025-03-24T06:16:37.005434627Z","message":"invalid-pool-load-balancing-algorithm","source":"vcap.gorouter","data":

{"poolLBAlgorithm":""}

,"stack_trace":"code.cloudfoundry.org/gorouter/route.

 

Resolution

This error has no functional impact in routing behaviour. 

Any version of TAS above 6.0.12 will have the fix for it.