Setup requirements and restrictions for stretch MetroCluster configurations with disks

You must follow certain requirements and restrictions when setting up a new stretch MetroCluster configuration with disks.

The requirements and restrictions for stretch MetroCluster configurations include those for a standard HA pair and those for a mirrored HA pair. In addition, the following requirements apply:

  • Starting with Data ONTAP 8.1 for FAS systems and 8.2 for V-Series systems, stretch MetroCluster configurations support SAS disk shelves when used with FibreBridge 6500N bridges.
  • Your storage system must meet all the compatibility requirements for FibreBridge 6500N bridges in the Interoperability Matrix at support.netapp.com/matrix.
  • The stretch MetroCluster configurations support SAS disk shelves using SAS optical cables.

    For more information about Data ONTAP versions supported for SAS optical cables with MetroCluster configurations, see the Hardware Universe at hwu.netapp.com.

  • Your storage system must meet all the compatibility requirements for SAS optical cables in the Interoperability Matrix at support.netapp.com/matrix.
  • SAS, SATA, and Fibre Channel storage is supported on stretch MetroCluster configurations, but both plexes of the same aggregate must use the same type of storage.
  • For a stretch MetroCluster configuration that uses SAS disk shelves, SAS copper cables are supported up to a distance of 20 meters.
  • For a stretch MetroCluster configuration that uses SAS disk shelves, SAS optical cables are supported up to a distance of 0 to 500 meters.
  • For stretch MetroCluster configurations using SAS disk shelves, either FibreBridge 6500N or SAS optical cables are required.
    Note: For stretch MetroCluster configurations using SAS disk shelves up to a distance of 20 meters, you can use SAS copper cables to connect the disk shelves directly to the controller.
  • For FAS systems, stacks of SAS disk shelves can be added to a MetroCluster configuration that has DS14mk4 FC disk shelves.
  • A stack of SAS disk shelves can contain shelves of SAS disk drives and shelves of SATA disk drives, but each SAS disk shelf can contain only SAS or SATA disk drives; you cannot mix SAS and SATA disk drives in the same disk shelf.

    To know about the number and the type of disk shelves supported in a stack, see the Interoperability Matrix on support.netapp.com/matrix.

  • For stretch MetroCluster configurations using SAS disk shelves and FibreBridge 6500N bridge, each stack requires two Fibre Channel ports on each controller.
  • While using SAS optical cables (when used with SAS disk shelves), you must ensure that there are sufficient SAS ports available on the storage system.
  • For the number of SAS disk shelves and the types of SAS disk shelves supported in a stack, see the Interoperability Matrix on support.netapp.com/matrix.
  • For a stretch MetroCluster configuration, if you have a 16-Gb FC-VI adapter with 16-Gb long range SFP connected by a 9/125µm single-mode fiber (SMF) cable, you can go up to 500m distance between nodes at the default 16-Gbps adapter speed.
  • The following distance limitations dictate the default speed you can set:
    • If the distance between the nodes is 150m and you have an 8-Gb FC-VI adapter, the default speed is set to 8 Gb.

      If you want to increase the distance to 270m or 500m, you can set the default speed to 4 Gb or 2 Gb, respectively.

    • If the distance between nodes is between 150m and 270m and you have an 8-Gb FC-VI adapter, you can set the default speed to 4 Gb.
    • If the distance between nodes is between 270m and 500m and you have an 8-Gb FC-VI or 4-Gb FC-VI adapter, you can set the default speed to 2 Gb.

    For more information about the distance limitation and the FC-VI adapter, see TR-3548, Best Practices for MetroCluster Design and Implementation, at the NetApp Support Site.

  • The following Data ONTAP options must be enabled on both nodes:
    • cf.mode

      This option must be set to ha.

    • cf.remote_syncmirror.enable

      This option must be set to on.

See the Interoperability Matrix on support.netapp.com/matrix for more information about hardware and firmware requirements for this configuration.