NSX-T Load-Balancer Pool-Member addition operation to a pool is getting failed in-cases where the same pool-member-IP+port combination is already present on that pool

Products

• VMware NSX

Issue/Introduction

To let the customers aware about an expected behavior when trying to add dublicate entry of pool-member-IP+port combination in same pool.

Symptoms:
1. You are using NSX-T Load-Balancer to host Virtual-Servers
2. Over UI or API you are trying to add a pool-member to a pool and you are getting the similar error,
UI:

API:

{
  "httpStatus" : "BAD_REQUEST",
  "error_code" : 502001,
  "module_name" : "policy",
  "error_message" : "Errors validating path=[/infra/lb-pools/Test-Pool].",
  "related_errors" : [ {
    "httpStatus" : "BAD_REQUEST",
    "error_code" : 502017,
    "module_name" : "policy",
    "error_message" : "There are more than one IpAddressPortPair in the IpPortList which have the same IP address 172.16.10.100 and port 22."
  } ]
}

3. Additionally on the 'nsxapi.log' on NSX-T Manager you would be seeing the similar error as well,

2024-02-29T07:24:50.435Z ERROR http-nio-127.0.0.1-7440-exec-10 LbPoolServiceImpl 4886 POLICY [nsx@6876 comp="nsx-manager" errorCode="PM502017" level="ERROR" reqId="dc31ef3d-####-####-####-########353" subcomp="manager" username="admin"] There are more than one pool member which have the same IP address 172.16.10.100 and port 22

2024-02-29T07:24:50.449Z  INFO http-nio-127.0.0.1-7440-exec-10 NsxBaseRestController 4886 SYSTEM [nsx@6876 comp="nsx-manager" level="INFO" subcomp="manager"] Error in API /nsxapi/api/v1/infra/lb-pools/Test-Pool caused by exception com.vmware.nsx.management.policy.loadbalancer.exceptions.LoadBalancerException:  {"moduleName":"policy","errorCode":502001,"errorMessage":"Errors validating path=[/infra/lb-pools/Test-Pool].","relatedErrors":[{"moduleName":"policy","errorCode":502017,"errorMessage":"There are more than one IpAddressPortPair in the IpPortList which have the same IP address 172.16.10.100 and port 22."}]}

2024-02-29T07:24:50.449Z  INFO http-nio-127.0.0.1-7440-exec-10 NsxBaseRestController 4886 SYSTEM [nsx@6876 audit="true" comp="nsx-manager" level="INFO" subcomp="manager"] UserName:'admin' ModuleName:'policy' Operation:'PUT@/api/v1/infra/lb-pools/Test-Pool' Operation status: 'failure' Error: Errors validating path=[/infra/lb-pools/Test-Pool].

Environment

VMware NSX-T
VMware NSX-T Data Center

Cause

In an NSX-T load-balancer pool we add pool-members to distribute the traffic between them. Hence, in the same pool, if we try to add multiple entries for same pool-member-IP+Port combination, that configuration is invalid in nature. To prevent such type of misconfiguration to be pushed in the data-plane, NSX-T manager have a validation workflow which detects this type of misconfiguration and throws error to let the administrator aware.

Resolution

This is an expected behavior of the NSX-T product. Each pool-member entry inside a pool should be having unique IP+Port combination

Workaround:
None