# DRC INSIGHT
# DRC INSIGHT Central Office Services (COS) Installation and Troubleshooting Ubuntu Linux
#
**Audience:** IT Administrators / MSP Engineers
**Platform:** Ubuntu 22.04 / 24.04 + Chromebook environments
---
## Overview
DRC INSIGHT Central Office Services (COS) is a local content hosting system that allows testing devices to retrieve assessment content from a local server instead of the internet.
**Key Concept:**
COS is a service-based HTTP system, NOT a file share.
Devices do NOT access /opt/CentralOffice directly.
---
## Architecture
```
Testing Devices
↓
DRC INSIGHT App
↓
COS Server
↓
Local Content (/opt/CentralOffice/content_fs)
↓
Fallback → DRC Cloud
```
---
## Installation (Ubuntu)
### 1. Update System
```
sudo apt update && sudo apt upgrade -y
```
### 2. Install Required Dependencies
```
sudo apt install -y \
libxcb-xinerama0 \
libalt-getopt-complete-perl \
libxcb-icccm4 \
libxcb-image0 \
libxcb-keysyms1 \
libxcb-render-util0 \
libxcb-xkb1 \
libxkbcommon-x11-0
```
**Critical:** Missing dependencies will cause silent installer failures or services crashing.
### 3. Fix /tmp Permissions
```
sudo chmod 1777 /tmp
ls -ld /tmp
```
### 4. Clean Previous Install
```
sudo rm -rf /opt/CentralOffice
sudo rm -f /tmp/coinstaller*.lock
```
### 5. Run Installer
```
chmod +x silent-linux.sh
sudo ./silent-linux.sh
```
---
## Registration (REQUIRED)
**Important:** You MUST open the setup URL generated during installation.
This step registers COS with DRC and enables services.
If skipped:
- Relay fails
- Contenthosting fails
- Devices cannot connect
---
## Validate Services
### Check Running Services
```
sudo /opt/CentralOffice/node \
/opt/CentralOffice/setup/node_modules/forever/bin/forever -p /opt/CentralOffice list
```
Expected:
- management
- relay
- proxy
- contenthosting
### Check Ports
```
sudo ss -tulnp | grep node
```
Typical Ports:
- 55223 – Content Hosting
- 55224 – Relay
- 55225 – Proxy
### Test Service
```
curl -I http://127.0.0.1:55223
```
HTTP 404 is normal and confirms the service is running.
---
## DRC Portal Configuration
### Content Management
- Enable Content Management → ON
- Select tests (PSSA, Keystone, CDT)
- Click Update Configuration
### Content Hosting
- Enable Content Hosting → ON
- Load Balancer → OFF
- Shared Content Location → OFF
Shared content should only be used in multi-server environments.
### Proxy
- Use Proxy → OFF
---
## Chromebook Configuration
### Install App
- Deploy DRC INSIGHT via Google Admin Console
### Register Device
```
Launch App → Assign Device to ORG Unit → Enter ORG ID
```
### Required Settings
- Display Scale = 100%
- Keyboard = US English
- Same network as COS
---
## Network Requirements
### Allowlist
```
*.drcedirect.com
```
### Ports
- 80 (HTTP)
- 443 (HTTPS)
### Internal COS Ports
```
sudo ufw allow 55223/tcp
sudo ufw allow 55224/tcp
sudo ufw allow 55225/tcp
```
---
## Content Validation
```
ls -lah /opt/CentralOffice/content_fs
```
```
sudo journalctl -u centralofficecontenthosting -f
```
---
## Troubleshooting
### Installer Fails
```
sudo chmod 1777 /tmp
sudo rm -rf /opt/CentralOffice
sudo ./silent-linux.sh
```
### Only Proxy Running
Cause: COS not registered
### Heartbeat Error
```
CO API - Heartbeat returned undefined
```
Fix:
- Complete setup URL
- Verify internet access
- Allow DRC domains
### Chromebooks Cannot Connect
- Verify ORG ID
- Check network
- Confirm ports open
---
## Validation Checklist
- \[ \] COS services running
- \[ \] Ports listening
- \[ \] Content downloading
- \[ \] Portal configured correctly
- \[ \] Chromebooks registered
---
## Key Takeaways
- COS is NOT a file server
- Uses HTTP endpoints
- Registration is required
- Content hosting must be enabled
---
**End of SOP**