AKS service with load balancer type is generating the IP but not able to access the service

Question

AKS service with load balancer type is generating the IP but not able to access the service and throwing the error

38m Normal EnsuringLoadBalancer service/kibana Ensuring load balancer
38m Warning UpdateLoadBalancerFailed service/kibana Error updating load balancer with new hosts map[aks-agentpool-70210429-0:{} aks-agentpool-70210429-1:{} aks-agentpool-70210429-2:{} aks-agentpool-70210429-3:{} aks-agentpool-70210429-4:{} aks-agentpool-70210429-5:{} aks-agentpool-70210429-6:{} aks-agentpool-70210429-8:{}]: Code="PreconditionFailed" Message="Precondition failed." Details=[{"code":"PreconditionFailedEtagMismatch","message":"Etag provided in if-match header W/\"50ee19c3-a727-44e6-8dea-0ad71318c6b8\" does not match etag W/\"9281675b-163a-46ef-b691-351414e95818\" of resource /subscriptions/a3156474-eead-4d25-ad9d-952bb6f94ed7/resourceGroups/mc_icsyndicate_icsyndicate-stg_westus2/providers/Microsoft.Network/loadBalancers/kubernetes in NRP data store."}]

Answer 1

Hello @Sudhakar Ummadi (iTalent Corporation)

This seems to be a temporary glitch where it was trying to check the Pre-Conditions , it's not exactly an issue . Retrying the same operation should go through fine. Kindly let me know if you still see the issue. It might have just happened due to the mismatch in the ETag (Basically ETag is used to maintain the concurrency)

This error might occur when sometimes if you are using a template for updating the Load Balancer which may be using an incorrect Etag.

Additional Verbose Details:-
From the back-end logs it seems Etag provided in if-match header of JSON file W/"50ee19c3-a727-44e6-8dea-0ad71318c6b8" does not match etag W/"9281675b-163a-46ef-b691-351414e95818" of resource /subscriptions/a3156474-eead-4d25-ad9d-952bb6f94ed7/resourceGroups/mc_icsyndicate_icsyndicate-stg_westus2/providers/Microsoft.Network/loadBalancers/kubernetes

Error Code: "PreconditionFailedEtagMismatch",
"message": "Etag provided in if-match header W/\"50ee19c3-a727-44e6-8dea-0ad71318c6b8\" does not match etag W/\"9281675b-163a-46ef-b691-351414e95818\" of resource /subscriptions/a3156474-eead-4d25-ad9d-952bb6f94ed7/resourceGroups/mc_icsyndicate_icsyndicate-stg_westus2/providers/Microsoft.Network/loadBalancers/kubernetes "

Basically , PUT REST API Operation is trying to validate and compare the tags provided in the header and the body - that validation is failing. Etag identifies specific versions of a resource and changes every time that resource is modified or update. Probably the load balancer or kubernetes might have modified prior to this operation