Platform: MCP Server

Nexus GSLB MCP Server

gslb-mcp is a Model Context Protocol server that exposes Nexus GSLB cluster state and configuration to AI platforms. Operators can query the live topology, get AI-assisted recommendations, and (optionally) apply configuration changes — all from tools like Claude Desktop, Cursor, or Zed.

Installation

Build from source alongside the other Nexus binaries:

<span id="cb1-1"><a href="#cb1-1" aria-hidden="true" tabindex="-1"></a><span class="va">CGO_ENABLED</span><span class="op">=</span>0 <span class="va">GOOS</span><span class="op">=</span>linux <span class="va">GOARCH</span><span class="op">=</span>amd64 <span class="ex">go</span> build <span class="at">-trimpath</span> <span class="at">-ldflags</span><span class="op">=</span><span class="st">&quot;-s -w&quot;</span> <span class="dt">\</span></span>
<span id="cb1-2"><a href="#cb1-2" aria-hidden="true" tabindex="-1"></a>  <span class="at">-o</span> gslb-mcp-linux-amd64 ./cmd/gslb-mcp</span>

Or run locally (macOS/Linux, native arch):

<span id="cb2-1"><a href="#cb2-1" aria-hidden="true" tabindex="-1"></a><span class="ex">go</span> build <span class="at">-o</span> gslb-mcp ./cmd/gslb-mcp</span>

Configuration

Flag Env var Required Description
--api-url NEXUS_API_URL Yes Base URL of the Nexus GSLB API, e.g. https://gslb.example.com
--api-key NEXUS_API_KEY Yes API key with at least read access
--allow-writes — No (default: off) Enable service-affecting write tools

Claude Desktop setup

Add to ~/Library/Application Support/Claude/claude_desktop_config.json:

<span id="cb3-1"><a href="#cb3-1" aria-hidden="true" tabindex="-1"></a><span class="fu">{</span></span>
<span id="cb3-2"><a href="#cb3-2" aria-hidden="true" tabindex="-1"></a>  <span class="dt">&quot;mcpServers&quot;</span><span class="fu">:</span> <span class="fu">{</span></span>
<span id="cb3-3"><a href="#cb3-3" aria-hidden="true" tabindex="-1"></a>    <span class="dt">&quot;nexus-gslb&quot;</span><span class="fu">:</span> <span class="fu">{</span></span>
<span id="cb3-4"><a href="#cb3-4" aria-hidden="true" tabindex="-1"></a>      <span class="dt">&quot;command&quot;</span><span class="fu">:</span> <span class="st">&quot;/usr/local/bin/gslb-mcp&quot;</span><span class="fu">,</span></span>
<span id="cb3-5"><a href="#cb3-5" aria-hidden="true" tabindex="-1"></a>      <span class="dt">&quot;args&quot;</span><span class="fu">:</span> <span class="ot">[]</span><span class="fu">,</span></span>
<span id="cb3-6"><a href="#cb3-6" aria-hidden="true" tabindex="-1"></a>      <span class="dt">&quot;env&quot;</span><span class="fu">:</span> <span class="fu">{</span></span>
<span id="cb3-7"><a href="#cb3-7" aria-hidden="true" tabindex="-1"></a>        <span class="dt">&quot;NEXUS_API_URL&quot;</span><span class="fu">:</span> <span class="st">&quot;https://gslb.example.com&quot;</span><span class="fu">,</span></span>
<span id="cb3-8"><a href="#cb3-8" aria-hidden="true" tabindex="-1"></a>        <span class="dt">&quot;NEXUS_API_KEY&quot;</span><span class="fu">:</span> <span class="st">&quot;your-api-key-here&quot;</span></span>
<span id="cb3-9"><a href="#cb3-9" aria-hidden="true" tabindex="-1"></a>      <span class="fu">}</span></span>
<span id="cb3-10"><a href="#cb3-10" aria-hidden="true" tabindex="-1"></a>    <span class="fu">}</span></span>
<span id="cb3-11"><a href="#cb3-11" aria-hidden="true" tabindex="-1"></a>  <span class="fu">}</span></span>
<span id="cb3-12"><a href="#cb3-12" aria-hidden="true" tabindex="-1"></a><span class="fu">}</span></span>

To enable write tools, add "--allow-writes" to the args array. See the write tools warning before doing so.

Read tools (always available)

These tools are safe to expose to any operator. They are read-only and have no effect on live traffic.

Core topology

Tool Description
get_topology Full cluster snapshot: services, pools, members, health. Start here.
get_dashboard_stats High-level health summary and counts
list_services All GSLB services with domain and algorithm
get_service Single service details (pool, algorithm, filter chain, TTL)
list_pools All member pools
get_pool Single pool details
get_pool_status Live health status for all members in a pool
list_members All members in a pool (IP, port, weight, region, enabled)
get_member Single member details
get_member_status Live health score for a member (0.0–1.0)
get_health_check Health check config for a pool
list_geo_rules Geo-routing rules for a pool

Observability

Tool Description
get_metrics_summary Per-service QPS and average latency from the last 60-second window

Cluster & infrastructure

Tool Description
get_cluster_status NATS cluster status, peer nodes, and JetStream metrics
get_cluster_report Detailed NATS cluster report: routes, streams, consumers, raft state
get_bgp_status BGP RHI advertisement status and prefix list
get_tls_status TLS mode, certificate subject/SANs/expiry, ACME config

DNS configuration

Tool Description
list_domains All delegated DNS zones
list_redirects All HTTP redirect rules
list_txt_records All static TXT DNS records
list_tsig_keys All TSIG keys for RFC 2136 dynamic DNS (secrets redacted)
list_rrl_allowlist All RRL-exempt CIDRs

DNSSEC

Tool Description
get_dnssec_status Signing status: active key IDs, rollover state
list_dnssec_keys All ZSK/KSK keys, algorithm, state, and expiry
get_dnssec_ds DS records for the active KSK (paste into parent zone)
get_dnssec_rollover_status Current rollover phase (pre-publish / double-signing / done)

Alerting

Tool Description
list_alert_channels All alert channels (SMTP, PagerDuty, OpsGenie, Webhook)
get_alert_channel Single channel details

Identity & access

Tool Description
list_users All user accounts (email, role, TOTP status)
list_roles All RBAC roles and permission sets
list_tenants All tenants
get_usage Resource counts vs. license limits for the current tenant
get_license License tier, feature limits, and expiry

Write tools

⚠️ WARNING — service-affecting

Write tools modify live cluster configuration. Changes take effect immediately in the DNS rotation and can cause traffic shifts, service disruptions, or member outages. Only enable --allow-writes if:

  • You have reviewed what each tool does
  • Your API key belongs to an account with appropriate permissions
  • Operators understand that the AI may make mistakes and should review actions before confirming them

Write tools are not registered unless the server is started with --allow-writes. This is intentional: the default mode is an AI assistant that helps operators understand the cluster and plan changes, not an autonomous agent that applies them.

Traffic management

Tool Impact
set_member_weight Shifts traffic distribution immediately
enable_member Adds a member back into the DNS rotation
disable_member Removes a member from the DNS rotation (no connection draining)
create_member Adds a new backend to a pool
delete_member Permanently removes a member (irreversible)
create_pool Creates an empty pool (no traffic impact until assigned to a service)
update_service Reassigns pool or changes algorithm for a service
upsert_health_check Creates or updates health check parameters for a pool

Alerting

Tool Impact
test_alert_channel Sends a test notification to verify channel delivery
create_alert_channel Creates a new notification channel
delete_alert_channel Permanently deletes a notification channel

DNS management

Tool Impact
create_txt_record Creates a static TXT record served immediately
delete_txt_record Deletes a TXT record (stops being served immediately)
create_redirect Creates an HTTP redirect rule (active immediately)
delete_redirect Deletes an HTTP redirect rule
  1. Ask the AI to call get_topology to load the current cluster state
  2. Describe what you want to achieve ("I want to shift all EU traffic to the new pool")
  3. The AI will analyse the topology and recommend the specific configuration steps
  4. Review the recommendation, then either apply it manually via the WebUI/TUI or ask the AI to apply it (write tools required)

This keeps the AI in an advisory role by default and makes human review an explicit step.

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