Kubernetes Operator

nexus-gslb-operator is a separate controller-runtime-based controller-manager (repo: nexus-gslb-operator, not part of this repo's build) that watches Service and Ingress objects in a Kubernetes cluster and keeps a matching Nexus GSLB pool/service/members in sync automatically. There are no CRDs — everything is driven by annotations, the same model as external-dns.

Annotate a Service or Ingress with nexus.gslb/hostname and the operator:

Find-or-creates a Nexus Pool (nexus.gslb/pool, default <namespace>-<name>). Pools are shared across objects/clusters that use the same pool name — a LoadBalancer Service in one cluster and another in a second cluster can both feed members into one pool for true multi-cluster failover.
Find-or-creates a Nexus Service (DNS record) per listed hostname, bound to that pool.
Resolves the object's externally-reachable address(es) — LB IP/hostname for type: LoadBalancer Services and Ingress frontends, or NodePort + node IPs for type: NodePort Services with Ready backing pods — and keeps the pool's members in sync.
On deletion, removes the members and DNS records it created. The pool itself is never auto-deleted, since other objects/clusters may still reference it.

Full annotation reference (nexus.gslb/algorithm, filter-chain, ttl, min-healthy, fallback-cname, weight, priority, region, target-port, endpoint-mode, node-address-type, …) lives in the operator repo's README.

Install

<span id="cb1-1"><a href="#cb1-1" aria-hidden="true" tabindex="-1"></a><span class="ex">helm</span> upgrade <span class="at">--install</span> nexus-gslb-operator ./charts/nexus-gslb-operator <span class="dt">\</span></span>
<span id="cb1-2"><a href="#cb1-2" aria-hidden="true" tabindex="-1"></a>  <span class="at">--namespace</span> nexus-system <span class="at">--create-namespace</span> <span class="dt">\</span></span>
<span id="cb1-3"><a href="#cb1-3" aria-hidden="true" tabindex="-1"></a>  <span class="at">--set</span> nexus.apiUrl=http://gslbd.nexus-system.svc.cluster.local:8080 <span class="dt">\</span></span>
<span id="cb1-4"><a href="#cb1-4" aria-hidden="true" tabindex="-1"></a>  <span class="at">--set</span> nexus.apiKey=<span class="op"><</span>tenant-or-system-api-key<span class="op">></span></span>

The API key is a normal Nexus tenant API key or the system break-glass key (/etc/gslb/env → GSLB_API_KEY on each node) — same auth path as gslbctl/Terraform, sent as a Bearer token.

RBAC

The operator needs cluster-wide read on Service/Node/EndpointSlice/ Ingress (to resolve member addresses) and write access to the specific objects it manages (to set finalizers/annotations). The Helm chart generates this; the equivalent raw manifest:

<span id="cb2-1"><a href="#cb2-1" aria-hidden="true" tabindex="-1"></a><span class="fu">apiVersion</span><span class="kw">:</span><span class="at"> rbac.authorization.k8s.io/v1</span></span>
<span id="cb2-2"><a href="#cb2-2" aria-hidden="true" tabindex="-1"></a><span class="fu">kind</span><span class="kw">:</span><span class="at"> ClusterRole</span></span>
<span id="cb2-3"><a href="#cb2-3" aria-hidden="true" tabindex="-1"></a><span class="fu">metadata</span><span class="kw">:</span></span>
<span id="cb2-4"><a href="#cb2-4" aria-hidden="true" tabindex="-1"></a><span class="at">  </span><span class="fu">name</span><span class="kw">:</span><span class="at"> nexus-gslb-operator</span></span>
<span id="cb2-5"><a href="#cb2-5" aria-hidden="true" tabindex="-1"></a><span class="fu">rules</span><span class="kw">:</span></span>
<span id="cb2-6"><a href="#cb2-6" aria-hidden="true" tabindex="-1"></a><span class="at">  </span><span class="kw">-</span><span class="at"> </span><span class="fu">apiGroups</span><span class="kw">:</span><span class="at"> </span><span class="kw">[</span><span class="st">&quot;&quot;</span><span class="kw">]</span></span>
<span id="cb2-7"><a href="#cb2-7" aria-hidden="true" tabindex="-1"></a><span class="at">    </span><span class="fu">resources</span><span class="kw">:</span><span class="at"> </span><span class="kw">[</span><span class="st">&quot;services&quot;</span><span class="kw">]</span></span>
<span id="cb2-8"><a href="#cb2-8" aria-hidden="true" tabindex="-1"></a><span class="at">    </span><span class="fu">verbs</span><span class="kw">:</span><span class="at"> </span><span class="kw">[</span><span class="st">&quot;get&quot;</span><span class="kw">,</span><span class="at"> </span><span class="st">&quot;list&quot;</span><span class="kw">,</span><span class="at"> </span><span class="st">&quot;watch&quot;</span><span class="kw">,</span><span class="at"> </span><span class="st">&quot;update&quot;</span><span class="kw">,</span><span class="at"> </span><span class="st">&quot;patch&quot;</span><span class="kw">]</span></span>
<span id="cb2-9"><a href="#cb2-9" aria-hidden="true" tabindex="-1"></a><span class="at">  </span><span class="kw">-</span><span class="at"> </span><span class="fu">apiGroups</span><span class="kw">:</span><span class="at"> </span><span class="kw">[</span><span class="st">&quot;&quot;</span><span class="kw">]</span></span>
<span id="cb2-10"><a href="#cb2-10" aria-hidden="true" tabindex="-1"></a><span class="at">    </span><span class="fu">resources</span><span class="kw">:</span><span class="at"> </span><span class="kw">[</span><span class="st">&quot;services/finalizers&quot;</span><span class="kw">]</span></span>
<span id="cb2-11"><a href="#cb2-11" aria-hidden="true" tabindex="-1"></a><span class="at">    </span><span class="fu">verbs</span><span class="kw">:</span><span class="at"> </span><span class="kw">[</span><span class="st">&quot;update&quot;</span><span class="kw">]</span></span>
<span id="cb2-12"><a href="#cb2-12" aria-hidden="true" tabindex="-1"></a><span class="at">  </span><span class="kw">-</span><span class="at"> </span><span class="fu">apiGroups</span><span class="kw">:</span><span class="at"> </span><span class="kw">[</span><span class="st">&quot;&quot;</span><span class="kw">]</span></span>
<span id="cb2-13"><a href="#cb2-13" aria-hidden="true" tabindex="-1"></a><span class="at">    </span><span class="fu">resources</span><span class="kw">:</span><span class="at"> </span><span class="kw">[</span><span class="st">&quot;nodes&quot;</span><span class="kw">]</span></span>
<span id="cb2-14"><a href="#cb2-14" aria-hidden="true" tabindex="-1"></a><span class="at">    </span><span class="fu">verbs</span><span class="kw">:</span><span class="at"> </span><span class="kw">[</span><span class="st">&quot;get&quot;</span><span class="kw">,</span><span class="at"> </span><span class="st">&quot;list&quot;</span><span class="kw">,</span><span class="at"> </span><span class="st">&quot;watch&quot;</span><span class="kw">]</span></span>
<span id="cb2-15"><a href="#cb2-15" aria-hidden="true" tabindex="-1"></a><span class="at">  </span><span class="kw">-</span><span class="at"> </span><span class="fu">apiGroups</span><span class="kw">:</span><span class="at"> </span><span class="kw">[</span><span class="st">&quot;&quot;</span><span class="kw">]</span></span>
<span id="cb2-16"><a href="#cb2-16" aria-hidden="true" tabindex="-1"></a><span class="at">    </span><span class="fu">resources</span><span class="kw">:</span><span class="at"> </span><span class="kw">[</span><span class="st">&quot;events&quot;</span><span class="kw">]</span></span>
<span id="cb2-17"><a href="#cb2-17" aria-hidden="true" tabindex="-1"></a><span class="at">    </span><span class="fu">verbs</span><span class="kw">:</span><span class="at"> </span><span class="kw">[</span><span class="st">&quot;create&quot;</span><span class="kw">,</span><span class="at"> </span><span class="st">&quot;patch&quot;</span><span class="kw">]</span></span>
<span id="cb2-18"><a href="#cb2-18" aria-hidden="true" tabindex="-1"></a><span class="at">  </span><span class="kw">-</span><span class="at"> </span><span class="fu">apiGroups</span><span class="kw">:</span><span class="at"> </span><span class="kw">[</span><span class="st">&quot;discovery.k8s.io&quot;</span><span class="kw">]</span></span>
<span id="cb2-19"><a href="#cb2-19" aria-hidden="true" tabindex="-1"></a><span class="at">    </span><span class="fu">resources</span><span class="kw">:</span><span class="at"> </span><span class="kw">[</span><span class="st">&quot;endpointslices&quot;</span><span class="kw">]</span></span>
<span id="cb2-20"><a href="#cb2-20" aria-hidden="true" tabindex="-1"></a><span class="at">    </span><span class="fu">verbs</span><span class="kw">:</span><span class="at"> </span><span class="kw">[</span><span class="st">&quot;get&quot;</span><span class="kw">,</span><span class="at"> </span><span class="st">&quot;list&quot;</span><span class="kw">,</span><span class="at"> </span><span class="st">&quot;watch&quot;</span><span class="kw">]</span></span>
<span id="cb2-21"><a href="#cb2-21" aria-hidden="true" tabindex="-1"></a><span class="at">  </span><span class="kw">-</span><span class="at"> </span><span class="fu">apiGroups</span><span class="kw">:</span><span class="at"> </span><span class="kw">[</span><span class="st">&quot;networking.k8s.io&quot;</span><span class="kw">]</span></span>
<span id="cb2-22"><a href="#cb2-22" aria-hidden="true" tabindex="-1"></a><span class="at">    </span><span class="fu">resources</span><span class="kw">:</span><span class="at"> </span><span class="kw">[</span><span class="st">&quot;ingresses&quot;</span><span class="kw">]</span></span>
<span id="cb2-23"><a href="#cb2-23" aria-hidden="true" tabindex="-1"></a><span class="at">    </span><span class="fu">verbs</span><span class="kw">:</span><span class="at"> </span><span class="kw">[</span><span class="st">&quot;get&quot;</span><span class="kw">,</span><span class="at"> </span><span class="st">&quot;list&quot;</span><span class="kw">,</span><span class="at"> </span><span class="st">&quot;watch&quot;</span><span class="kw">,</span><span class="at"> </span><span class="st">&quot;update&quot;</span><span class="kw">,</span><span class="at"> </span><span class="st">&quot;patch&quot;</span><span class="kw">]</span></span>
<span id="cb2-24"><a href="#cb2-24" aria-hidden="true" tabindex="-1"></a><span class="at">  </span><span class="kw">-</span><span class="at"> </span><span class="fu">apiGroups</span><span class="kw">:</span><span class="at"> </span><span class="kw">[</span><span class="st">&quot;networking.k8s.io&quot;</span><span class="kw">]</span></span>
<span id="cb2-25"><a href="#cb2-25" aria-hidden="true" tabindex="-1"></a><span class="at">    </span><span class="fu">resources</span><span class="kw">:</span><span class="at"> </span><span class="kw">[</span><span class="st">&quot;ingresses/finalizers&quot;</span><span class="kw">]</span></span>
<span id="cb2-26"><a href="#cb2-26" aria-hidden="true" tabindex="-1"></a><span class="at">    </span><span class="fu">verbs</span><span class="kw">:</span><span class="at"> </span><span class="kw">[</span><span class="st">&quot;update&quot;</span><span class="kw">]</span></span>

Set rbac.clusterScoped: false (Helm) for a namespaced Role/RoleBinding instead, if you restrict watchNamespace and only ever use LoadBalancer-backed Services/Ingresses (NodePort resolution needs cluster-wide Node visibility).

Runs under OpenShift's default restricted/restricted-v2 SCC — the pod spec only requests runAsNonRoot: true, no fixed UID.

Known limitations

ClusterIP Services don't get members (not externally routable); the Nexus Service/Pool are still created so DNS resolves via the pool's fallback CNAME once members do appear.
Node IP changes for NodePort members are only picked up via EndpointSlice events plus the manager's cache resync, not a direct Node watch.
Pools are never auto-deleted by the operator; prune unused ones via gslbctl or the API.

Surface parity

API ✅ (existing pools/members/services endpoints) WebUI N/A (k8s-native, annotation-driven) TUI N/A Terraform N/A (separate operator/Helm install path, not a Terraform-managed resource) Kubernetes ✅ (this page) Docs ✅