UpdateBackend for loadbalancer is not getting updated about oci-python-sdk

[arthall]

From my understanding of the docs, update_backend only updates the settings supplied with update_backend_details. It can't be used to change the change the backend_name. The API returns a header, opc-work-request-id, which can be used with get_work_request. You will probably find an error in the work request.

https://docs.cloud.oracle.com/iaas/api/#/en/loadbalancer/20170115/Backend/UpdateBackend

I think update_backend_set is the API you need to change a backend server. https://docs.cloud.oracle.com/iaas/api/#/en/loadbalancer/20170115/BackendSet/UpdateBackendSet

[adizohar]

Any update on load balancer resources will create a work-request, please check the work request if it failed or completed, you can use get_work_request(work_request_id, **kwargs) to check it

[sreecharanm]

please check my code below:

---

def updateBackend(lbr,backendsetname,newip):
# print(type(newTimeOutVal))
config = oci.config.from_file(file_location="~/.oci/config", profile_name="DEFAULT")
lb_cli = oci.load_balancer.LoadBalancerClient(config)
backend_dict = dict(lb_cli.get_load_balancer(lbr).data.backend_sets)
print("the dict data is ",backend_dict)
print("the ocid is",)
#print("the dict is", lb_dict)
dictlist=[]
for key, value in backend_dict.items():
temp = [key, value]
dictlist.append(temp)

for key in backend_dict.keys():
    # if key == listner :
    print("*********************")
    backends  = backend_dict[key].backends
    print(type(backends))
    print(backend_dict[key].name)
    mylist = []
    print ("the backends are",backends)
    if (len(backends)) > 0:
        for  backendietm in backends:
            print("**************")

            print("the backenditems are",backendietm)

            print("**************")
            backendset_details = oci.load_balancer.models.UpdateBackendSetDetails(policy=backend_dict[key].policy,backends=backends,health_checker=backend_dict[key].health_checker)
            print("************************************************")
            print("the abckendset_details are",backendset_details)

            print("calling update_backend_set")
            print("the backendset details are",backendset_details.backends)
            print("the backendset name",backend_dict[key].name)
            print("the lbr is",lbr)
            print("*****************")




            print("Getting the Backend Details")
            print("************************************")
            newip = "10.0.0.4:90";
            #lb_backend = lb_cli.get_backend(load_balancer_id=lbr,backend_set_name=backend_dict[key].name,backend_name="newip")
            #lb_cli.update_backend_set(update_backend_set_details=backends,load_balancer_id=lbr,backend_set_name=backend_dict[key].name)
            print("&&&&&&&&&&&&&&&&&&&&&&&")

            backenddetails = oci.load_balancer.models.UpdateBackendDetails(weight=1, backup=backendietm.backup,
                                                                           drain=backendietm.drain,
                                                                           offline=backendietm.offline)

            print("backenddetails are",backenddetails)

            print("set set set ",backend_dict[key].name)
            print("****************************")

           lb_cli.update_backend(update_backend_details=backenddetails, load_balancer_id=lbr, backend_set_name=backend_dict[key].name, backend_name=newip)

updateBackend("ocid1.loadbalancer.oc1.iad.********************","lb-20190416-****-backend-set","10.0.0.4:90")

Here I am calling the (update_backend method )

Parameters:	update_backend_details (UpdateBackendDetails) -- (required) Details for updating a backend server.load_balancer_id (str) --(required) The OCID of the load balancer associated with the backend set and server.backend_set_name (str) --(required) The name of the backend set associated with the backend server.Example: example_backend_setbackend_name (str) --(required) The IP address and port of the backend server to update.Example: 10.0.0.3:8080opc_request_id (str) -- (optional) The unique Oracle-assigned identifier for the request. If you need to contact Oracle about a particular request, please provide the request ID.opc_retry_token (str) -- (optional) A token that uniquely identifies a request so it can be retried in case of a timeout or server error without risk of executing that same action again. Retry tokens expire after 24 hours, but can be invalidated before then due to conflicting operations (e.g., if a resource has been deleted and purged from the system, then a retry of the original creation request may be rejected).retry_strategy (obj) --(optional) A retry strategy to apply to this specific operation/call. This will override any retry strategy set at the client-level.This should be one of the strategies available in the retry module. A convenience DEFAULT_RETRY_STRATEGY is also available. The specifics of the default retry strategy are described here.To have this operation explicitly not perform any retries, pass an instance of NoneRetryStrategy.
A Response object with data of type None
Response

the O/P I am getting is:

---

backend set name that I am getting is : lb-20190416-****-backend-set

---

type of backendset {
"backends": [
{
"backup": false,
"drain": false,
"ip_address": "10.0.0.4",
"name": "10.0.0.4:80",
"offline": false,
"port": 80,
"weight": 1
}
],
"health_checker": {
"interval_in_millis": 100000,
"port": 80,
"protocol": "HTTP",
"response_body_regex": "",
"retries": 3,
"return_code": 200,
"timeout_in_millis": 3000,
"url_path": "/"
},
"policy": "ROUND_ROBIN",
"session_persistence_configuration": null,
"ssl_configuration": null
}

Process finished with exit code 0

[sreecharanm]

if I update with the same ip and port it is getting succeeded whereas if I give the new "ip" and "port" it is not getting updated. please check the below. please check the Work Requests:

[arthall]

Based on your code it seems like you are trying to switch one backend server for another backend server. You cannot do this with update_backend. You can only update the properties of a backend using update_backend. This is why you see the update_backend work requests succeed when you supply an IP address and port which exists in the backend set and see them fail when you supply a new IP address and port. The load balancer figures out which backend you want to update using the IP address and port. When you supply an IP address and port of a backend that is not part of the backend set the load balancer cannot perform an update_backend because it cannot find the backend to update.

You have to use update_backend_set to add or remove backends from the backend set.
https://docs.cloud.oracle.com/iaas/api/#/en/loadbalancer/20170115/BackendSet/UpdateBackendSet

I think these pages may help https://docs.cloud.oracle.com/iaas/Content/Balance/Concepts/balanceoverview.htm and https://docs.cloud.oracle.com/iaas/Content/GSG/Tasks/loadbalancing.htm#Add

[sreecharanm]

Getting the backend set details:

---

backenddetails = oci.load_balancer.models.UpdateBackendDetails(weight=1, backup=backendietm.backup,
drain=backendietm.drain,
offline=backendietm.offline)

updating the backend details

---

lb_cli.update_backend(update_backend_details=backenddetails, load_balancer_id=lbr, backend_set_name=backend_dict[key].name, backend_name=backendietm.name)

As you said in the UpdateBackendDetails we don't have the property backend_name.

Here my requirement is to update the ipaddr and port. where as in the api i got the method update_backed to update the backend_name.

Correct me if i am wrong. And please let me know from which method we can update the backend_name. please let me know the flow.

[arthall]

You cannot change the backend_name with update_backend. You need to add the new server to the backend set using update_backend_set. Backend_name is composed of the IP address and port, but it is readonly and cannot be used to set the IP address and port of a backend.

The API call you need is update_backend_set.
If you have "10.0.0.4:80" in your backend set but you want "10.0.0.5:80" you have to remove "10.0.0.4:80" and add "10.0.0.5:80" using update_backend_set. Once you have updated the backend set you will see the name "10.0.0.5:80" in your list of backends.

[arthall]

@sreecharanm, were you able to get the backend updated?

[arthall]

@sreecharanm, I'm going to close this ticket, assuming everything is working for you now. Please reopen it if that is not the situation.