Background of issue:
There are 4 ldap servers in the ldap cluster, but when one of the node is down, the gateway has got more than 80% errors, not the expected 25%.
The ldap identity provider is configured 2 ldap urls pointing to the load balancer of the cluster with different ports.
Release : 9.0
Component : API GTW ENTERPRISE MANAGER
The ldap url is configured to use the hostname of the load balancer of the ldap cluster.
When the ldap connection is fail, the gateway will put the ldap url in the black list for a minute by default, then the whole cluster is not available during that period(not just one node).
For multiple ldap urls, the gateway will try to use the first available ldap url, and keep using it until it fails, then put it in black list and try next ldap url.
https://techdocs.broadcom.com/us/en/ca-enterprise-software/layer7-api-management/api-gateway/10-0/reference/gateway-cluster-properties/ldap-cluster-properties.html
https://techdocs.broadcom.com/us/en/ca-enterprise-software/layer7-api-management/api-gateway/10-0/security-configuration-in-policy-manager/identity-providers/ldap-identity-providers/simple-ldap-identity-provider-wizard.html