Skip to content
Menu
IT-DRAFTS
  • About
  • My Statistics at Microsoft Q&A
  • Privacy policy
IT-DRAFTS
May 13, 2025May 13, 2025

Work around the OCSP validation issue in Azure Application Gateway

1. First, verify connectivity to OCSP responder from Azure’s network:

bash
# Create a test VM in the same subnet as your App Gateway
az vm create --resource-group MyResourceGroup --name TestVM --image UbuntuLTS --vnet-name MyVNet --subnet MySubnet --admin-username azureuser

# SSH into the VM and test OCSP responder
openssl ocsp -issuer intermediate.crt -cert client.crt -url http://ocsp.yourca.com -text

2. Check current SSL policy settings:

bash
az network application-gateway ssl-policy show \
    --resource-group MyResourceGroup \
    --gateway-name MyAppGateway

3. Disable OCSP stapling (workaround):

bash
az network application-gateway ssl-policy set \
    --resource-group MyResourceGroup \
    --gateway-name MyAppGateway \
    --name AppGwSslPolicy \
    --disabled-ssl-protocols TLSv1_0 TLSv1_1 \
    --policy-type Custom \
    --cipher-suites 'TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384' 'TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256' \
    --min-protocol-version TLSv1_2 \
    --no-ocsp-stapling

4. Enable verbose logging for troubleshooting:

bash
az monitor diagnostic-settings create \
    --resource /subscriptions/xxxx/resourceGroups/MyResourceGroup/providers/Microsoft.Network/applicationGateways/MyAppGateway \
    --name AppGWDiagnostics \
    --logs '[{"category":"ApplicationGatewayAccessLog","enabled":true},{"category":"ApplicationGatewayPerformanceLog","enabled":true},{"category":"ApplicationGatewayFirewallLog","enabled":true}]' \
    --workspace /subscriptions/xxxx/resourcegroups/MyResourceGroup/providers/microsoft.operationalinsights/workspaces/MyLogAnalytics

5. If needed, force CRL-based revocation instead:

bash
az network application-gateway http-settings update \
    --resource-group MyResourceGroup \
    --gateway-name MyAppGateway \
    --name myhttpsettings \
    --ssl-cert <cert-name> \
    --crl-enabled true

6. To check SSL handshake failures:

bash
az network application-gateway waf-config show \
    --resource-group MyResourceGroup \
    --gateway-name MyAppGateway

For the permanent fix, I recommend opening a support ticket with these details:

bash
az support tickets create \
    --title "OCSP Validation Failure in App Gateway" \
    --description "OCSP works externally but fails in App Gateway" \
    --severity minimal \
    --contact-email "rajeev@example.com" \
    --contact-phone "1234567890" \
    --contact-first-name "Rajeev" \
    --contact-last-name "G" \
    --subtype "Technical" \
    --problem-classification "/providers/Microsoft.Support/services/{serviceGUID}/problemClassifications/{problemClassificationGUID}"

 

RGDS,

Alex

Categories

ActiveDirectory AI Azure AzureAI azureinfrastructure BetaChannel cloudarchitecture cloudnetworking CloudSecurity Conditional Access Copilot Cybersecurity DataProtection DataSecurity DevOps devsecops DNS enterpriseai Entra entraID Howto hybridcloud Innovation licensing MFA Microsoft Microsoft365 Microsoft AI MicrosoftAzure microsoftcloud MicrosoftOffice Microsoft Product MicrosoftSentinel NewRelease OfficeSuite promptinjection Security SoftwareUpdate TechNews Technology updates Windows Windows10 Windows11 zeroTrust

Archives

  • July 2025
  • June 2025
  • May 2025
  • February 2025
  • October 2024
  • September 2024
  • July 2024
  • June 2024
  • May 2024
  • April 2024
  • March 2024
No comments to show.

Recent Comments

Recent Posts

  • 🧨 SUDO, YOU HAD ONE JOB!
  • Azure WAF vs Entra External ID: When Your Firewall Starts Shooting the Good Guys
  • DPAPI: The Granddaddy of Windows Crypto (and your secrets)
  • Microsoft Just Threw Windows Licensing into the Cloud — And Locked It Inside Confidential VMs
  • Windows LAPS with Intune: One admin password per device, finally.
©2025 IT-DRAFTS | Powered by WordPress and Superb Themes!