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DRC INSIGHT Central Office Services (COS) Installation and Troubleshooting SOPe


Overview

This SOP provides step-by-step instructions to install, configure, validate, and troubleshoot the DRC INSIGHT Central Office Services (COS) Service Device on Linux, with deployment notes for Chromebooks and portal configuration guidance.

1. Purpose

The COS Service Device provides local content hosting for DRC INSIGHT testing devices. This reduces internet dependency, improves consistency during testing, and allows testing content to be delivered from the local network instead of the cloud whenever COS is available.

2. DRC COS Architecture

Testing Devices
    ↓
DRC INSIGHT Secure App
    ↓
COS Service Device
    ↓
Local Content Hosting
    ↓
Fallback to DRC Cloud if COS unavailable

DRC describes the COS Service Device as a local content hosting device, and notes that testing devices can connect to any supported COS operating system type. The training deck also shows that test content is delivered from the COS Service Device when available, and from CloudFront if the COS Service Device is unavailable. :contentReference[oaicite:0]{index=0}

3. Supported Platforms

  • Testing Devices: Windows, macOS, Linux, iPadOS, and ChromeOS
  • COS Service Devices: Windows, macOS, and Linux

DRC's August 2025 Pennsylvania training deck states that DRC INSIGHT Secure Applications are supported on Windows, macOS, Linux, iPadOS, and ChromeOS, while COS Service Devices are supported on Windows, macOS, and Linux. :contentReference[oaicite:1]{index=1}

4. Linux Installation Procedure

4.1 Prepare the System

sudo apt update
sudo apt install -y curl unzip
sudo chmod 1777 /tmp
ls -ld /tmp

The /tmp directory must be writable. A failed COS install can occur if the installer cannot create its temporary lock file.

4.2 Clean Up a Failed Installation

sudo rm -rf /opt/CentralOffice
sudo rm -f /tmp/coinstaller*.lock

4.3 Run the Installer

chmod +x silent-linux.sh
sudo ./silent-linux.sh

DRC recommends using the default locations during installation. The training deck also states that the installation wizard will present a completion URL that should be saved because it can be used to resume the process without reinstalling the COS Service Device. :contentReference[oaicite:2]{index=2}

4.4 Default COS Service Ports

According to the DRC training deck, the installer typically uses a base port of 55222, and then automatically assigns consecutive ports. :contentReference[oaicite:3]{index=3}

In this deployment, the observed active ports were:

  • 55223
  • 55224
  • 55225

5. Verify COS Services

5.1 Check Registered Services

systemctl list-unit-files | grep -Ei 'central|drc|relay|proxy|content'

5.2 Check Running Node Processes

sudo /opt/CentralOffice/node \
/opt/CentralOffice/setup/node_modules/forever/bin/forever -p /opt/CentralOffice list

Expected running components:

  • management
  • relay
  • proxy
  • contenthosting

5.3 Check Listening Ports

sudo ss -tulnp | grep node

5.4 Validate Local HTTP Response

curl -I http://127.0.0.1:55223
curl -I http://127.0.0.1:55224
curl -I http://127.0.0.1:55225

An HTTP 404 on the root path does not necessarily indicate failure. It confirms that the HTTP service is alive but may require a specific application route.

6. DRC Portal Configuration

6.1 Content Management

  • Enable Content Management: ON
  • Select the appropriate administrations and accommodations
  • Click Update Configuration

The training deck states that Content Management is used to select the testing content and accommodations to be hosted on the COS Service Device. It also notes that VSL must be selected each year, while TTS/HVA may remain checked from the prior year. :contentReference[oaicite:4]{index=4}

6.2 Content Hosting

  • Enable Content Hosting: ON
  • Load Balancer: OFF for a single COS server deployment
  • Shared Content Location: OFF for a single COS server deployment

Use a shared content location only if there is an actual shared multi-server content design. For a single local COS server, leave shared content disabled and let COS manage local storage internally.

6.3 Proxy Configuration

  • Use Proxy Host or Restricted Proxy: OFF unless specifically required by the site design

For a normal single COS Service Device deployment, avoid unnecessary proxy layering unless DRC support or site network policy requires it.

7. Device Registration

The training deck states that devices with the DRC INSIGHT Secure Application are registered to a COS Configuration, and that one way to assign testing devices is to manually assign the COS ORG Unit ID. :contentReference[oaicite:5]{index=5}

7.1 Register a Device Manually

  1. Launch DRC INSIGHT
  2. Select Assign Device to ORG Unit
  3. Enter the COS ORG Unit ID
  4. Select Register

8. Chromebook Deployment SOP

8.1 Install the App

DRC states that for ChromeOS, the installer is available through a Google Play deployment path and should be deployed using the Google Admin console. :contentReference[oaicite:6]{index=6}

8.2 Chromebook Settings Required by DRC

  • Display Size must be set to 100%
  • Keyboard must be set to US English

The Pennsylvania training deck specifically states that ChromeOS display size should be 100%, and that ChromeOS devices must use the US English keyboard so quotation marks and apostrophes display correctly. :contentReference[oaicite:7]{index=7}

  • Register each device to the correct COS ORG Unit ID
  • Keep devices on the same network as the COS Service Device during testing
  • Run the System Readiness Check before testing

9. Network and Firewall Requirements

9.1 Internal Network

Allow testing devices to reach the COS server on the configured service ports.

sudo ufw allow 55223/tcp
sudo ufw allow 55224/tcp
sudo ufw allow 55225/tcp

9.2 DRC Allowlist

The DRC training deck lists a shared allowlist and states that wildcard *.drcedirect.com should be allowed, with ports 80 and 443 permitted. :contentReference[oaicite:8]{index=8}

Key URLs from the deck include:

  • https://api-gateway.drcedirect.com
  • https://api-gateway-cloud.drcedirect.com
  • https://cdn-content-prod.drcedirect.com
  • https://cdn-download-prod.drcedirect.com
  • https://drc-centraloffice.com
  • https://dtk.drcedirect.com
  • https://wbte.drcedirect.com
  • https://www.drcedirect.com

9.3 Ports

  • 80 / HTTP
  • 443 / HTTPS

10. Validate Content Download

10.1 Check Local Content Directory

ls -lah /opt/CentralOffice/content_fs

Content should populate after the configuration is updated and the required administrations are selected.

10.2 Monitor Content Services

sudo journalctl -u centralofficecontenthosting -f
sudo journalctl -u centralofficerelay -f

11. Troubleshooting SOP

11.1 Installer Fails or Stops Early

Symptoms:

  • Missing COS files under /opt/CentralOffice
  • Installer exits without completing
  • Lock file errors in /tmp

Fix:

sudo chmod 1777 /tmp
sudo rm -rf /opt/CentralOffice
sudo rm -f /tmp/coinstaller*.lock
sudo ./silent-linux.sh

11.2 Only Proxy Runs

Symptoms:

  • forever list shows only proxy
  • Other services appear to start but do not stay up

Fix:

Complete the DRC registration/setup URL generated during installation and confirm portal configuration. After registration, restart all COS services.

11.3 Relay Error: Heartbeat returned undefined

Observed error:

Error: CO API - Heartbeat returned undefined

Meaning:

The relay could start but did not receive the expected heartbeat response from the DRC Central Office API. This usually indicates incomplete registration, missing configuration, or upstream reachability issues.

Checks:

  • Confirm the registration/setup URL was completed
  • Confirm outbound internet access
  • Confirm DRC allowlist is permitted
  • Confirm TLS inspection is not interfering

11.4 Services Show "active (exited)"

This may be expected. COS uses forever to launch the Node services in the background, so systemd may show the wrapper script as exited while the actual service continues under Node. Use forever list as the primary runtime check.

11.5 Chromebooks Cannot Load Tests

Checks:

  • Confirm the DRC INSIGHT app is installed
  • Confirm device is assigned to the correct ORG Unit ID
  • Confirm Chromebook display is set to 100%
  • Confirm keyboard is US English
  • Confirm the device can reach the COS server
  • Confirm the COS configuration is green before testing

12. Operational Best Practices

  • Use a dedicated COS Service Device when possible
  • Keep COS online overnight so updates can occur
  • Verify configuration status is green before daily testing
  • Run readiness checks before test windows
  • Temporarily disable disruptive background apps and updates on testing devices

The training deck recommends reviewing background processes and temporarily disabling automatic updates and software that could interfere with testing. Examples listed include classroom monitoring tools, remote access tools, collaboration tools, screen capture software, and typing assistants. :contentReference[oaicite:9]{index=9}

13. Validation Checklist

COS Server

  • [ ] COS installer completed successfully
  • [ ] Registration/setup URL completed
  • [ ] management, relay, proxy, and contenthosting visible in forever list
  • [ ] Ports listening
  • [ ] Local content path populated

Portal

  • [ ] Content Management enabled
  • [ ] Correct administrations selected
  • [ ] Content Hosting enabled
  • [ ] Shared Content disabled for single-server design
  • [ ] Load Balancer disabled for single-server design

Chromebooks

  • [ ] DRC INSIGHT deployed
  • [ ] ORG Unit ID assigned
  • [ ] Display size 100%
  • [ ] US English keyboard
  • [ ] Same network reachability to COS

14. DRC Resources

The DRC training deck lists the following readiness and support resources in the portal:

  • Site Readiness Overview
  • System Requirements
  • Technology User Guide
  • Site Technology Readiness Checklist
  • Site Capacity Estimator
  • Online Testing Network Evaluation Checklist
  • COS Service Device Decision Guide
  • All-in-One Quick Reference Guides
  • Technical Bulletin: Extended Retries

The deck also references the online testing system status page:

Status URL: https://status.drcedirect.com/PA

15. Support Contacts

DRC PA Customer Service

  • Phone: (800) 451-7849
  • Email: PAcustomerservice@datarecognitioncorp.com

DRC WIDA Customer Service

  • Phone: (855) 787-9615
  • Email: wida@datarecognitioncorp.com

End of SOP

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