page_title: NetApp FAS
section_title: MetroCluster
hierarchical_section_title: NetApp FAS / Hardware / MetroCluster
caption_attribution_description: English: MetroCluster replication using plexes
context_page_description: A NetApp FAS is a computer storage product by NetApp running the ONTAP operating system; the terms ONTAP, AFF, ASA, FAS are often used as synonyms. "Filer" is also used as a synonym although this is not an official name. There are three types of FAS systems: Hybrid, All-Flash, and All SAN Array:
  NetApp proprietary custom-build hardware appliances with HDD or SSD drives called hybrid Fabric-Attached Storage
  NetApp proprietary custom-build hardware appliances with only SSD drives and optimized ONTAP for low latency called ALL-Flash FAS
  All SAN Array build ontop of AFF platform, and provide only SAN-based data protocol connectivity.
  ONTAP can serve storage over a network using file-based protocols such as NFS and SMB, also block-based protocols, such as the SCSI over the Fibre Channel Protocol on a Fibre Channel network, Fibre Channel over Ethernet, iSCSI, and FC-NVMe transport layer. ONTAP-based systems that can serve both SAN and NAS protocols called Unified ONTAP, AFF systems with ASA identity called All-SAN.
  NetApp storage systems running ONTAP implement their physical storage in large disk arrays.
context_section_description: MetroCluster (MC) is free functionality for FAS and AFF systems for metro high availability with synchronous replication between two sites, this configuration requires additional equipment. Available in both modes: 7-mode (old OS) and Cluster-Mode (or cDOT - a newer version of ONTAP OS). MetroCluster in Cluster-Mode known as MCC. MetroCluster uses RAID SyncMirror (RSM) and plex technique where on one site number of disks form one or more RAID groups aggregated in a plex, while on the second site have the same number of disks with the same type and RAID configuration alongside with Configuration Replication Service (CRS) and NVLog replication. One plex synchronously replicates to another in a compound with non-volatile memory. Two plexes form an aggregate where data stored and in case of disaster on one site second site provide read-write access to data. MetroCluster Support FlexArray technology. MetroCluster configurations are possible only with mid-range and high-end models which provide the ability to install additional network cards required to MC to function.
caption: SyncMirror replication using plexes
exif: {}