• Secure Mobile Access 12.4
• About This Guide
• CMS Configuration
  • Introduction to CMS
    • Overview
    • CMS Deployment Options
    • What’s New in This Release
      • Global Policy Settings
      • CMS Alerts Logging
    • Central Management Server
    • Central Management Console
    • Managed Appliances
    • Licensing CMS
    • Central User Licenses
    • Global Traffic Optimizer
    • FIPS and CMS
    • Getting Started in Five Steps
  • Installing and Configuring the Central Management Server
    • Overview
    • Kernel based Virtual Machine
    • Supported Platforms for CMS with Global HA
    • Hardware Resource Requirements
    • Installation Files
    • Setting Up a CMS
  • Configuring Appliances for Central Management
    • Overview
    • Firmware Compatibility with the CMS
    • Enabling Central Management on SMA Appliance
    • Registering an SMA Appliance with the CMS
    • Previously Configured Appliances
  • Using the Management Console Menus
    • Overview
    • Dashboard
      • Alerts
      • Appliances Pane
      • Appliance Load
      • Central License Usage Pane
      • About Pane
    • Management Server
      • Alerts
        • View Alerts
        • Configure Alerts
        • Notification
      • Configure
        • Central Management Settings
        • CMS Address Pool
        • Licensing
        • Administrators
          • General Settings
        • Network Settings
        • SSL Settings
        • Services
          • Manage SSH settings from CMS
      • Monitor
        • Configure the logging setting for Managed appliances
      • Maintain
    • Managed Appliances
      • Add/Remove
      • Configure
        • Overview
        • Configuring the Managed Appliances
          • Define Policy
          • Synchronize
        • Support multiple policies with CMS and shared licensing
          • Applying authentication servers to specific appliance
          • Applying SMTP configuration service to specific appliance
          • Applying SMS service to specific appliance
          • Applying realms to a subset of appliance
          • Assign rules to a subset of appliances
          • Support multiple GTO services
      • Monitor
        • User Sessions
        • Reports
        • Health
      • Maintain
  • Central User Licensing
    • Overview
    • How Central User Licenses Work
      • Central Spike User Licenses
      • Central Email Licenses
      • Perpetual Pooled Licenses
    • Enabling Central User Licensing
    • Getting Started with Central User Licensing
      • Setting Up CMS to Use Central User Licenses
      • Setting up CMS for Centralized Appliance Configuration and Management
      • Resetting a CMS License
  • Global High Availability
    • High Availability of the VPN Service
    • High Availability of the CMS
    • Disaster Recovery for the VPN Service
  • Alerts and SNMP
    • Overview
    • Pre-Configured Alerts
    • Configuring SNMP
  • Capture Advanced Threat Protection
    • Enabling Capture ATP
    • File Options
    • Web Services
    • Advanced Settings
  • Central FIPS Licensing
• Global High Availablity
  • Introduction to Global HA and GTO
  • Planning GTO Deployment
    • Choosing a Deployment Model
    • Minimizing Configuration Differences
    • GTO Service Names and DNS Delegations
    • Provisioning Certificates
      • Let's Encrypt
      • Adding Certificates to SMA Appliances
      • Generating a Certificate Signing Request (CSR)
      • Importing SSL Certificates
  • Setting up GTO
    • Setting up the CMS and SMA appliances
    • Enabling GTO service for managed appliances with the CMS
    • Setting up a Basic GTO Service
    • Monitoring and Configuring GTO
    • Defining the Central Policy
  • Extending GTO Deployment
    • Enabling Cached Credentials
    • Additional Deployment Notes
• SonicWall Support
  • About This Document

Additional Deployment Notes

Notes on SMA Appliances

It is recommended that you configure a minimum of two SMA appliances, and that you delegate them in DNS as authoritative servers to minimize the likelihood that your users ever lose DNS resolution of the GTO service.

You must enable UDP 53 on your firewall for all traffic that is sent to CMS-managed appliances that are configured as authoritative servers.

Web Limitations if an Appliance Fails

Web users may face some limitations with GTO if an appliance fails. GTO services should DNS-resolve to more than one MA node, and web browsers given a multi-address DNS response should connect to the first address that works. When CMS finds an MA unresponsive for a minute, it instructs the DNS authoritative server nodes to reconfigure around the broken MA, but during that reconfiguration time, the broken MA node can still appear in DNS responses. If this situation occurs and the user’s Workplace session fails, the user sees what looks like a typical failure of a website. The user needs to reconnect by retyping the GTO service name. They are redirected through a different node and can access that web site again.