---
title: "Enterprise Node Communication Requirements"
slug: "enterprise-node-command-and-control"
updated: 2025-09-23T20:44:42Z
published: 2025-09-23T20:44:42Z
canonical: "docs.catchpoint.com/enterprise-node-command-and-control"
---

> ## Documentation Index
> Fetch the complete documentation index at: https://docs.catchpoint.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Enterprise Node Communication Requirements

Enterprise Nodes must be able to continuously communicate with Catchpoint Command & Control (C&C) to retrieve targeted tests and to report test results. This article provides best practices for allowing traffic to and from Catchpoint's C&C servers.

---

## **Quick Allowlist**

- **Allow outbound traffic from your Enterprise Nodes to:**
  - `*.3gl.net`
  - `*.catchpoint.com`
- **No inbound rules required.**

## **Recommended Policy**

Catchpoint recommends allowing the Fully Qualified Domain Names (FQDNs) for communication between Enterprise Nodes and Command & Control (C&C). Hosts/IPs can change, so FQDN allowlisting is the simplest and most reliable method.

- **FQDN allowlisting (recommended):**
  - Permit outbound HTTPS (443) to `*.3gl.net` and `*.catchpoint.com`.
- **IP allowlisting (last resort / resilience):**
  - If your policy restricts the use of FQDN wildcards, or if you want added resilience against DNS issues, configure automation to pull the current C&C IPs via the REST API and allow outbound access to those IPs. (See [Getting IPs Programmatically](/v1/docs/enterprise-node-command-and-control#getting-ips-programmatically-optional) below for instructions.) If you are comfortable with the node pausing when DNS is unavailable, allowing only FQDNs is sufficient.
- **Automatic failover behavior:**
  - Nodes try primary C&C FQDNs; if that fails, they try secondary FQDNs.
  - If DNS resolution fails, Nodes fall back to HTTP on port 80 using IPs so testing can continue (when permitted by policy).

          
          

Static, hand-maintained IP lists are brittle. Either allow FQDN wildcards or automate IP retrieval via the API.

---

#### **Connectivity & Ports**

- **Outbound only** from Enterprise Nodes to C&C.
- **Primary path:** HTTPS on port 443 to `*.3gl.net` / `*.catchpoint.com`.
- **Fallback during DNS failure:** HTTP on port 80 to IPs (if allowed by your policy).

---

## **Getting IPs Programmatically (Optional)**

Use the Catchpoint REST API to retrieve the current C&C IPs:

- **Endpoint:** `GET https://io.catchpoint.com/api/v2/commandcontrol`
- **Guidance:** Use the API as specified in the [Catchpoint REST API Documentation](/v1/docs/rest-api-guide).

### Sample Response (Illustration Only)

          
          

**Note: This IP list is not live and may be out of date. It’s provided only as an illustration of the API response.**

```
["64.147.163.212",  "las-syn-sch-01.3gl.net",  "64.147.163.54",  "64.147.163.55",  "64.147.163.56",  "64.147.163.57",  "64.79.149.218",  "64.147.163.53",  "las-syn-sch-02.3gl.net",  "64.79.149.202",  "swpt.webpagetest.org",  "3.22.10.38",  "139.178.87.138",  "139.178.87.142",  "64.79.149.104",  "las-syn-sch-07.3gl.net",  "64.147.163.213",  "64.79.149.217",  "147.75.46.198",  "147.75.46.194",  "147.28.148.242",  "147.75.202.214",  "147.75.202.218",  "145.40.97.166",  "145.40.97.162",  "23.92.67.138",  "195.242.152.2",  "8.134.149.27",  "147.28.148.246",  "47.242.152.170",  "107.155.109.98",  "74.177.169.33",  "20.26.76.1",  "172.212.66.210",  "34.48.10.113",  "34.86.197.139",  "48.218.233.197",  "48.218.202.175",  "4.145.24.152",  "144.202.14.34",  "9.141.22.100",  "13.76.140.21",  "172.211.42.108",  "45.63.94.40",  "135.149.76.49",  "64.147.163.58",  "64.147.163.59",  "149.28.223.76",  "las-syn-log-01.3gl.net",  "64.147.163.211",  "las-syn-log-02.3gl.net",  "64.147.163.52",  "dfw-eqx-sch-17.3gl.net",  "dfw-eqx-log-17.3gl.net",  "64.147.163.209",  "las-syn-log-07.3gl.net",  "sin-eqx-sch-01.3gl.net",  "sin-eqx-log-01.3gl.net",  "dfw-eqx-log-01.3gl.net",  "sjc-eqx-sch-01.3gl.net",  "sjc-eqx-log-01.3gl.net",  "ams-eqx-log-01.3gl.net",  "ams-eqx-sch-01.3gl.net",  "nyc-hv-capt-01.3gl.net",  "fra-hv-capt-01.3gl.net",  "dfw-eqx-sch-11.3gl.net",  "lhr-az-log-01.3gl.net",  "lhr-az-sch-01.3gl.net",  "iad-az-cc-01.3gl.net",  "iad-gcp-log-01.3gl.net",  "iad-gcp-sch-01.3gl.net",  "nrt-az-log-01.3gl.net",  "nrt-az-sch-01.3gl.net",  "phx-az-capt-01.3gl.net",  "sin-az-capt-01.3gl.net",  "sfo-az-cc-01.3gl.net",  "l11.3gl.net",  "s04.3gl.net",  "s05.3gl.net",  "l04.3gl.net",  "l05.3gl.net",  "s10.3gl.net",  "l10.3gl.net",  "s11.3gl.net",  "c04.3gl.net",  "d04.3gl.net",  "c05.3gl.net",  "d05.3gl.net",  "c10.3gl.net",  "d10.3gl.net",  "c11.3gl.net",  "d11.3gl.net",  "img.3gl.net",  "nyc-vl-capt-01.3gl.net",  "fra-az-capt-05.3gl.net",  "sin-az-capt-05.3gl.net",  "lax-hv-capt-01.3gl.net",  "ams-az-capt-01.3gl.net",  "sjc-vl-sch-06.3gl.net",  "sea-vl-capt-01.3gl.net",  "las-syn-sch-06.3gl.net",  "las-syn-log-06.3gl.net",  "sjc-vl-sch-01.3gl.net"]
```

---

## **Verify Your Allowlist (Simple Health Check)**

Fetch `robots.txt` from allowed domains.

### Example Health Check Request

```
curl -sSf https://s.3gl.net/robots.txt
```

### Pass Criteria

A healthy response consists of HTTP 200 and exactly the following response body:

```
User-agent: *
Disallow: /
```

Note: Timeouts/name-resolution errors or intermediary 40x/50x usually indicate blocking.

---

## **Troubleshooting Tips**

- **DNS errors/timeouts:**
  - Allow FQDNs and ensure resolvers are reachable. If you intentionally block DNS, add IP allowlisting from the API so the HTTP/80 fallback can succeed.
- **HTTPS blocked:**
  - Permit outbound 443 to `*.3gl.net` and `*.catchpoint.com`.
- **Intermittent success:**
  - Often due to partial allowlists. Prefer FQDN wildcards or refresh IPs from the API on a schedule.

## **Change Management**

- Endpoints/IPs can change occasionally. Use the REST API to access the current IP list
- Services will always live under subdomains of `3gl.net` and `catchpoint.com`.

## **Support**

Questions? Contact support@catchpoint.com or open ticket via [help center](https://support.catchpoint.com/hc/en-us/).
