Considerations for session-oriented protocols


Clusters and session-oriented protocols might cause adverse effects on clients and applications in certain areas during upgrades.

If you are using session-oriented protocols, consider the following:

  • CIFS

    Hyper-V and SQL Server over SMB support nondisruptive operations (NDOs). If you configured a Hyper-V or SQL Server over SMB solution, the application servers and the contained virtual machines or databases remain online and provide continuous availability during the ONTAP upgrade.

    For all other CIFS configurations, client sessions are terminated. You should direct users to end their sessions before you upgrade.

  • NFSv4.x

    NFSv4.x clients will automatically recover from connection losses experienced during the upgrade using normal NFSv4.x recovery procedures. Applications might experience a temporary I/O delay during this process.

  • NDMP

    State is lost and the client user must retry the operation.

  • Backups and restores

    State is lost and the client user must retry the operation.

    Important Do not initiate a backup or restore during or immediately before an upgrade. Doing so might result in data loss.
  • Applications (for example, Oracle or Exchange)

    Effects depend on the applications. For timeout-based applications, you might be able to change the timeout setting to longer than the ONTAP reboot time to minimize adverse effects.