seikaikyo/deploying-cloudflare-access-for-zero-trust

Deploying Cloudflare Access for Zero Trust

When to Use

• When replacing VPN infrastructure with identity-aware application access using Cloudflare One
• When exposing self-hosted internal applications through Cloudflare Tunnel without opening inbound ports
• When implementing ZTNA for a distributed workforce accessing web applications, SSH, and RDP services
• When needing a cost-effective zero trust solution with integrated DLP, CASB, and SWG capabilities
• When securing contractor and third-party access to specific applications without full network access

Do not use for applications requiring persistent UDP connections not supported by Cloudflare Tunnel, for environments requiring air-gapped or fully on-premises access control, or when regulatory requirements prohibit routing traffic through third-party cloud infrastructure.

Prerequisites

• Cloudflare account with Zero Trust subscription (Free for up to 50 users, paid plans for larger teams)
• Domain name managed by Cloudflare DNS (or ability to add CNAME records)
• Linux, Windows, or macOS server to run cloudflared tunnel daemon
• Identity provider: Okta, Microsoft Entra ID, Google Workspace, GitHub, or any SAML/OIDC provider
• Cloudflare WARP client for device-level enrollment (optional but recommended)

Workflow

Step 1: Create a Cloudflare Tunnel to Internal Applications

Install cloudflared and create a persistent tunnel to expose internal services.

# Install cloudflared on Ubuntu/Debian
curl -L https://github.com/cloudflare/cloudflared/releases/latest/download/cloudflared-linux-amd64.deb \
  -o cloudflared.deb
sudo dpkg -i cloudflared.deb

# Authenticate cloudflared with your Cloudflare account
cloudflared tunnel login

# Create a named tunnel
cloudflared tunnel create internal-apps
# Output: Created tunnel internal-apps with id xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx

# Configure tunnel routes to internal applications
cat > ~/.cloudflared/config.yml << 'EOF'
tunnel: xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx
credentials-file: /home/admin/.cloudflared/xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx.json

ingress:
  - hostname: wiki.company.com
    service: http://localhost:8080
  - hostname: git.company.com
    service: http://10.1.1.50:3000
  - hostname: grafana.company.com
    service: http://10.1.1.60:3000
  - hostname: ssh.company.com
    service: ssh://localhost:22
  - hostname: rdp.company.com
    service: rdp://10.1.1.100:3389
  # Catch-all rule (required)
  - service: http_status:404
EOF

# Route DNS to the tunnel
cloudflared tunnel route dns internal-apps wiki.company.com
cloudflared tunnel route dns internal-apps git.company.com
cloudflared tunnel route dns internal-apps grafana.company.com

# Run tunnel as a systemd service
sudo cloudflared service install
sudo systemctl enable cloudflared
sudo systemctl start cloudflared

# Verify tunnel status
cloudflared tunnel info internal-apps

Step 2: Configure Identity Provider Integration

Set up authentication with your organization's identity provider.

# Using Cloudflare API to configure Okta as IdP
curl -X PUT "https://api.cloudflare.com/client/v4/accounts/{account_id}/access/identity_providers" \
  -H "Authorization: Bearer ${CF_API_TOKEN}" \
  -H "Content-Type: application/json" \
  --data '{
    "name": "Corporate Okta",
    "type": "okta",
    "config": {
      "client_id": "OKTA_CLIENT_ID",
      "client_secret": "OKTA_CLIENT_SECRET",
      "okta_account": "company.okta.com",
      "api_token": "OKTA_API_TOKEN",
      "claims": ["email", "groups", "name"],
      "email_claim_name": "email"
    }
  }'

# Configure Microsoft Entra ID as additional IdP
curl -X POST "https://api.cloudflare.com/client/v4/accounts/{account_id}/access/identity_providers" \
  -H "Authorization: Bearer ${CF_API_TOKEN}" \
  -H "Content-Type: application/json" \
  --data '{
    "name": "Microsoft Entra ID",
    "type": "azureAD",
    "config": {
      "client_id": "AZURE_APP_CLIENT_ID",
      "client_secret": "AZURE_APP_CLIENT_SECRET",
      "directory_id": "AZURE_TENANT_ID",
      "support_groups": true,
      "claims": ["email", "groups", "name"]
    }
  }'

Step 3: Create Access Applications and Policies

Define Access applications with identity-aware policies for each internal service.

# Create Access application for internal wiki
curl -X POST "https://api.cloudflare.com/client/v4/accounts/{account_id}/access/apps" \
  -H "Authorization: Bearer ${CF_API_TOKEN}" \
  -H "Content-Type: application/json" \
  --data '{
    "name": "Internal Wiki",
    "domain": "wiki.company.com",
    "type": "self_hosted",
    "session_duration": "8h",
    "auto_redirect_to_identity": true,
    "http_only_cookie_attribute": true,
    "same_site_cookie_attribute": "lax",
    "logo_url": "https://company.com/wiki-logo.png",
    "allowed_idps": ["OKTA_IDP_ID", "AZURE_IDP_ID"]
  }'

# Create Allow policy for the wiki application
curl -X POST "https://api.cloudflare.com/client/v4/accounts/{account_id}/access/apps/{app_id}/policies" \
  -H "Authorization: Bearer ${CF_API_TOKEN}" \
  -H "Content-Type: application/json" \
  --data '{
    "name": "Allow Engineering Team",
    "decision": "allow",
    "precedence": 1,
    "include": [
      {"group": {"id": "ENGINEERING_GROUP_ID"}},
      {"okta": {"name": "Engineering", "identity_provider_id": "OKTA_IDP_ID"}}
    ],
    "require": [
      {"device_posture": {"integration_uid": "CROWDSTRIKE_INTEGRATION_ID"}}
    ]
  }'

# Create Access application for SSH access
curl -X POST "https://api.cloudflare.com/client/v4/accounts/{account_id}/access/apps" \
  -H "Authorization: Bearer ${CF_API_TOKEN}" \
  -H "Content-Type: application/json" \
  --data '{
    "name": "SSH Access",
    "domain": "ssh.company.com",
    "type": "ssh",
    "session_duration": "4h",
    "auto_redirect_to_identity": true
  }'

Step 4: Deploy WARP Client for Device Enrollment

Enroll corporate devices using Cloudflare WARP for private network access and device posture.

# Create device enrollment rule
curl -X POST "https://api.cloudflare.com/client/v4/accounts/{account_id}/devices/policy" \
  -H "Authorization: Bearer ${CF_API_TOKEN}" \
  -H "Content-Type: application/json" \
  --data '{
    "name": "Corporate Device Enrollment",
    "match": "identity.email matches \".*@company\\.com$\"",
    "precedence": 100,
    "enabled": true,
    "gateway_unique_id": "GATEWAY_ID",
    "support_url": "https://helpdesk.company.com/warp-help"
  }'

# Install WARP on macOS via MDM (Jamf/Intune)
# Download: https://developers.cloudflare.com/cloudflare-one/connections/connect-devices/warp/download-warp/
# Deploy with MDM configuration profile:
cat > warp_mdm_config.plist << 'EOF'
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
<dict>
    <key>organization</key>
    <string>company</string>
    <key>auto_connect</key>
    <integer>1</integer>
    <key>switch_locked</key>
    <true/>
    <key>onboarding</key>
    <false/>
</dict>
</plist>
EOF

# Install Cloudflare root certificate for TLS inspection
# Download from: https://developers.cloudflare.com/cloudflare-one/connections/connect-devices/warp/user-side-certificates/
sudo cp cloudflare-root-ca.pem /usr/local/share/ca-certificates/cloudflare-root-ca.crt
sudo update-ca-certificates

# Configure split tunnel to route private network through WARP
curl -X PUT "https://api.cloudflare.com/client/v4/accounts/{account_id}/devices/policy/{policy_id}/fallback_domains" \
  -H "Authorization: Bearer ${CF_API_TOKEN}" \
  -H "Content-Type: application/json" \
  --data '[
    {"suffix": "internal.corp", "description": "Internal corporate domain"},
    {"suffix": "10.0.0.0/8", "description": "Private network range"}
  ]'

Step 5: Configure Device Posture Checks

Integrate endpoint security signals into Access policies.

# Add CrowdStrike device posture integration
curl -X POST "https://api.cloudflare.com/client/v4/accounts/{account_id}/devices/posture/integration" \
  -H "Authorization: Bearer ${CF_API_TOKEN}" \
  -H "Content-Type: application/json" \
  --data '{
    "name": "CrowdStrike Falcon",
    "type": "crowdstrike_s2s",
    "config": {
      "api_url": "https://api.crowdstrike.com",
      "client_id": "CS_API_CLIENT_ID",
      "client_secret": "CS_API_CLIENT_SECRET",
      "customer_id": "CS_CUSTOMER_ID"
    },
    "interval": "10m"
  }'

# Create device posture rule for disk encryption
curl -X POST "https://api.cloudflare.com/client/v4/accounts/{account_id}/devices/posture" \
  -H "Authorization: Bearer ${CF_API_TOKEN}" \
  -H "Content-Type: application/json" \
  --data '{
    "name": "Disk Encryption Required",
    "type": "disk_encryption",
    "match": [{"platform": "windows"}, {"platform": "mac"}],
    "input": {"requireAll": true}
  }'

# Create device posture rule for OS version
curl -X POST "https://api.cloudflare.com/client/v4/accounts/{account_id}/devices/posture" \
  -H "Authorization: Bearer ${CF_API_TOKEN}" \
  -H "Content-Type: application/json" \
  --data '{
    "name": "Minimum OS Version",
    "type": "os_version",
    "match": [{"platform": "windows"}],
    "input": {"version": "10.0.19045", "operator": ">="}
  }'

Step 6: Set Up Audit Logging and Analytics

Configure logging for access decisions and tunnel health monitoring.

# Enable Logpush for Access audit logs to S3
curl -X POST "https://api.cloudflare.com/client/v4/accounts/{account_id}/logpush/jobs" \
  -H "Authorization: Bearer ${CF_API_TOKEN}" \
  -H "Content-Type: application/json" \
  --data '{
    "name": "access-audit-logs",
    "output_options": {
      "field_names": ["RayID","Action","Allowed","AppDomain","AppUUID","Connection","Country","CreatedAt","Email","IPAddress","PurposeJustificationPrompt","PurposeJustificationResponse","TemporaryAccessDuration","UserUID"],
      "timestamp_format": "rfc3339"
    },
    "destination_conf": "s3://security-logs-bucket/cloudflare-access/?region=us-east-1&access-key-id=AKID&secret-access-key=SECRET",
    "dataset": "access_requests",
    "enabled": true
  }'

# Query access logs via GraphQL Analytics API
curl -X POST "https://api.cloudflare.com/client/v4/graphql" \
  -H "Authorization: Bearer ${CF_API_TOKEN}" \
  -H "Content-Type: application/json" \
  --data '{
    "query": "{ viewer { accounts(filter: {accountTag: \"ACCOUNT_ID\"}) { accessLoginRequestsAdaptiveGroups(filter: {datetime_gt: \"2026-02-22T00:00:00Z\"}, limit: 100, orderBy: [count_DESC]) { dimensions { action appName userEmail country } count } } } }"
  }'

Key Concepts

| Term | Definition | |------|------------| | Cloudflare Tunnel | Encrypted outbound-only connection from your infrastructure to Cloudflare's network, exposing internal services without opening inbound firewall ports | | Cloudflare Access | Identity-aware reverse proxy evaluating every request against access policies before granting access to protected applications | | WARP Client | Cloudflare's endpoint agent that routes device traffic through Cloudflare's network for policy enforcement and private network access | | Access Application | Configuration object defining a protected resource (self-hosted, SaaS, or infrastructure) with associated access policies | | Device Posture | Endpoint health signals (OS version, disk encryption, EDR status) evaluated as conditions in Access policies | | Cloudflare One | Unified SASE platform combining ZTNA (Access), SWG (Gateway), CASB, DLP, and RBI |

Tools & Systems

• Cloudflare Access: Identity-aware application proxy providing per-request authorization
• Cloudflare Tunnel (cloudflared): Daemon creating encrypted tunnels from internal networks to Cloudflare edge
• WARP Client: Cross-platform endpoint agent for device enrollment, DNS filtering, and private network routing
• Cloudflare Gateway: Secure Web Gateway providing DNS/HTTP filtering and DLP inspection
• Cloudflare Logpush: Real-time log streaming to external SIEM and storage destinations
• Access for Infrastructure: SSH and RDP access with short-lived certificates and session recording

Common Scenarios

Scenario: Startup with 200 Employees Deploying Zero Trust from Scratch

Context: A SaaS startup with 200 employees and no existing VPN wants to provide secure access to internal tools (Grafana, internal APIs, staging environments) running on AWS. Budget is limited, and the team has no dedicated security staff.

Approach:

1. Start with Cloudflare Zero Trust free tier (up to 50 users) for proof of concept
2. Deploy one cloudflared tunnel on an EC2 instance in the production VPC
3. Expose Grafana, internal wiki, and staging apps through tunnel with DNS routing
4. Configure Google Workspace as IdP for SSO authentication
5. Create Access policies requiring @company.com email domain for all applications
6. Add device posture checks for disk encryption and OS version
7. Upgrade to paid plan and deploy WARP client to all employee laptops via MDM
8. Enable Gateway DNS filtering and HTTP inspection for malware protection
9. Configure Logpush to send access logs to Datadog for monitoring

Pitfalls: Cloudflare root certificate must be installed on all devices for TLS inspection to work; some applications may break with TLS interception. Tunnel failover requires running multiple cloudflared instances or using Cloudflare's replicas feature. Access policies should always include a default deny rule. WebSocket applications may require specific tunnel configuration.

Output Format

Cloudflare Zero Trust Deployment Report
==================================================
Organization: StartupCorp
Team Name: startupcorp
Deployment Date: 2026-02-23

TUNNEL INFRASTRUCTURE:
  Active Tunnels: 2 (primary + failover)
  Tunnel Status: Healthy
  Connected Edge: Washington DC, Ashburn
  Ingress Routes: 8

ACCESS APPLICATIONS:
  Self-Hosted Apps: 6
  SaaS Apps: 3
  SSH/Infrastructure: 2
  Total Policies: 15

DEVICE ENROLLMENT:
  Enrolled Devices: 187 / 200
  WARP Connected: 182 / 187 (97.3%)
  Posture Compliant: 175 / 187 (93.6%)

ACCESS METRICS (last 30 days):
  Total Requests: 89,432
  Allowed: 88,756 (99.2%)
  Blocked: 676 (0.8%)
  Unique Users: 195
  Countries: 12
  Avg Session Duration: 6.2 hours