Facing issue while configuring egress IP pool in OCP cluster which uses STS

It is a disconnected cluster on AWS. There is an issue configuring Egress IP where the cluster uses STS. While looking into cloud-network-config-controller pod it is trying to connect to the global sts service "https://sts.amazonaws.com/" rather it should connect to the regional one "https://ec2.ap-southeast-1.amazonaws.com".

Always

1. Create a disconected OCP cluster on AWS.

$ oc get netnamespace | grep egress
egress-ip-test                                     2689387    ["172.16.1.24"]

$ oc get hostsubnet
NAME                                              HOST                                              HOST IP        SUBNET          EGRESS CIDRS   EGRESS IPS
ip-172-16-1-151.ap-southeast-1.compute.internal   ip-172-16-1-151.ap-southeast-1.compute.internal   172.16.1.151   10.130.0.0/23                  
ip-172-16-1-53.ap-southeast-1.compute.internal    ip-172-16-1-53.ap-southeast-1.compute.internal    172.16.1.53    10.131.0.0/23                  ["172.16.1.24"]
ip-172-16-2-15.ap-southeast-1.compute.internal    ip-172-16-2-15.ap-southeast-1.compute.internal    172.16.2.15    10.128.0.0/23                  
ip-172-16-2-77.ap-southeast-1.compute.internal    ip-172-16-2-77.ap-southeast-1.compute.internal    172.16.2.77    10.128.2.0/23                  
ip-172-16-3-111.ap-southeast-1.compute.internal   ip-172-16-3-111.ap-southeast-1.compute.internal   172.16.3.111   10.129.0.0/23                  
ip-172-16-3-79.ap-southeast-1.compute.internal    ip-172-16-3-79.ap-southeast-1.compute.internal    172.16.3.79    10.129.2.0/23                  

$ oc logs sdn-controller-6m5kb -n openshift-sdn I0922 04:09:53.348615       1 vnids.go:105] Allocated netid 2689387 for namespace "egress-ip-test"
E0922 04:24:00.682018       1 egressip.go:254] Ignoring invalid HostSubnet ip-172-16-1-53.ap-southeast-1.compute.internal (host: "ip-172-16-1-53.ap-southeast-1.compute.internal", ip: "172.16.1.53", subnet: "10.131.0.0/23"): related node object "ip-172-16-1-53.ap-southeast-1.compute.internal" has an incomplete annotation "cloud.network.openshift.io/egress-ipconfig", CloudEgressIPConfig: <nil>

 $ oc logs cloud-network-config-controller-5c7556db9f-x78bs -n openshift-cloud-network-config-controller

E0922 04:26:59.468726       1 controller.go:165] error syncing 'ip-172-16-2-77.ap-southeast-1.compute.internal': error retrieving the private IP configuration for node: ip-172-16-2-77.ap-southeast-1.compute.internal, err: error: cannot list ec2 instance for node: ip-172-16-2-77.ap-southeast-1.compute.internal, err: WebIdentityErr: failed to retrieve credentials
caused by: RequestError: send request failed
caused by: Post "https://sts.amazonaws.com/": dial tcp 54.239.29.25:443: i/o timeout, requeuing in node workqueue

$ oc get Infrastructure -o yaml
apiVersion: v1
items:
- apiVersion: config.openshift.io/v1
  kind: Infrastructure
  metadata:
    creationTimestamp: "2022-09-22T03:28:15Z"
    generation: 1
    name: cluster
    resourceVersion: "598"
    uid: 994da301-2a96-43b7-b43b-4b7c18d4b716
  spec:
    cloudConfig:
      name: ""
    platformSpec:
      aws:
        serviceEndpoints:
        - name: sts
          url: https://sts.ap-southeast-1.amazonaws.com
        - name: ec2
          url: https://ec2.ap-southeast-1.amazonaws.com
        - name: elasticloadbalancing
          url: https://elasticloadbalancing.ap-southeast-1.amazonaws.com
      type: AWS
  status:
    apiServerInternalURI: https://api-int.openshiftyy.ocpaws.sadiqueonline.com:6443
    apiServerURL: https://api.openshiftyy.ocpaws.sadiqueonline.com:6443
    controlPlaneTopology: HighlyAvailable
    etcdDiscoveryDomain: ""
    infrastructureName: openshiftyy-wfrpf
    infrastructureTopology: HighlyAvailable
    platform: AWS
    platformStatus:
      aws:
        region: ap-southeast-1
        serviceEndpoints:
        - name: ec2
          url: https://ec2.ap-southeast-1.amazonaws.com
        - name: elasticloadbalancing
          url: https://elasticloadbalancing.ap-southeast-1.amazonaws.com
        - name: sts
          url: https://sts.ap-southeast-1.amazonaws.com
      type: AWS
kind: List
metadata:
  resourceVersion: ""

$ oc get secret aws-cloud-credentials -n openshift-machine-api -o json |jq -r .data.credentials |base64 -d 
[default]
sts_regional_endpoints = regional
role_arn = arn:aws:iam::015719942846:role/sputhenp-sts-yy-openshift-machine-api-aws-cloud-credentials
web_identity_token_file = /var/run/secrets/openshift/serviceaccount/token
 
[ec2-user@ip-172-17-1-229 ~]$ oc get secret cloud-credential-operator-iam-ro-creds -n openshift-cloud-credential-operator -o json |jq -r .data.credentials |base64 -d 
[default]
sts_regional_endpoints = regional
role_arn = arn:aws:iam::015719942846:role/sputhenp-sts-yy-openshift-cloud-credential-operator-cloud-creden
web_identity_token_file = /var/run/secrets/openshift/serviceaccount/token
 
[ec2-user@ip-172-17-1-229 ~]$ oc get secret installer-cloud-credentials -n openshift-image-registry -o json |jq -r .data.credentials |base64 -d 
[default]
sts_regional_endpoints = regional
role_arn = arn:aws:iam::015719942846:role/sputhenp-sts-yy-openshift-image-registry-installer-cloud-credent
web_identity_token_file = /var/run/secrets/openshift/serviceaccount/token
 
[ec2-user@ip-172-17-1-229 ~]$ oc get secret cloud-credentials -n openshift-ingress-operator -o json |jq -r .data.credentials |base64 -d 
[default]
sts_regional_endpoints = regional
role_arn = arn:aws:iam::015719942846:role/sputhenp-sts-yy-openshift-ingress-operator-cloud-credentials
web_identity_token_file = /var/run/secrets/openshift/serviceaccount/token
 
[ec2-user@ip-172-17-1-229 ~]$ oc get secret cloud-credentials -n openshift-cloud-network-config-controller -o json |jq -r .data.credentials |base64 -d 
[default]
sts_regional_endpoints = regional
role_arn = arn:aws:iam::015719942846:role/sputhenp-sts-yy-openshift-cloud-network-config-controller-cloud-
web_identity_token_file = /var/run/secrets/openshift/serviceaccount/token
 
[ec2-user@ip-172-17-1-229 ~]$ oc get secret ebs-cloud-credentials -n openshift-cluster-csi-drivers -o json |jq -r .data.credentials |base64 -d
[default]
sts_regional_endpoints = regional
role_arn = arn:aws:iam::015719942846:role/sputhenp-sts-yy-openshift-cluster-csi-drivers-ebs-cloud-credenti
web_identity_token_file = /var/run/secrets/openshift/serviceaccount/token
 

Egress IP not configured properly and cloud-network-config-controller trying to connect to global STS service.

Egress IP should get configured and cloud-network-config-controller should connect to regional STS service instead of global.