# Comparison of distributed file systems

In computing, a distributed file system (DFS) or network file system is any file system that allows access from multiple hosts to files shared via a computer network. This makes it possible for multiple users on multiple machines to share files and storage resources.
Distributed file systems differ in their performance, mutability of content, handling of concurrent writes, handling of permanent or temporary loss of nodes or storage, and their policy of storing content.

## Locally managed
### FOSS

| Client | Written in | License | Access API | High availability | Shards | Efficient Redundancy | Redundancy Granularity | Initial release year | Memory requirements (GB) |
| Alluxio (Virtual Distributed File System) | Java | Apache License 2.0 | HDFS, FUSE, HTTP/REST, S3 | hot standby | No | Replication | File | 2013 | |
| Ceph | C++ | LGPL | librados (C, C++, Python, Ruby), S3, Swift, FUSE | Yes | Yes | Pluggable erasure codes | Pool | 2010 | 1 per TB of storage |
| Coda | C | GPL | C | Yes | Yes | Replication | Volume | 1987 | |
| GlusterFS | C | GPLv3 | libglusterfs, FUSE, NFS, SMB, Swift, libgfapi | mirror | Yes | Reed-Solomon | Volume | 2005 | |
| HDFS | Java | Apache License 2.0 | Java and C client, HTTP, FUSE | transparent master failover | No | Reed-Solomon | File | 2005 | |
| IPFS | Go | Apache 2.0 or MIT | HTTP gateway, FUSE, Go client, Javascript client, command line tool | Yes | with IPFS Cluster | Replication | Block | 2015 | |
| LizardFS | C++ | GPLv3 | POSIX, FUSE, NFS-Ganesha, Ceph FSAL (via libcephfs) | master | No | Reed-Solomon | File | 2013 | |
| Lustre | C | GPLv2 | POSIX, NFS-Ganesha, NFS, SMB | Yes | Yes | No redundancy | No redundancy | 2003 | |
| MinIO | Go | AGPL3.0 | AWS S3 API, FTP, SFTP | Yes | Yes | Reed-Solomon | Object | 2014 | |
| MooseFS | C | GPLv2 | POSIX, FUSE | master | No | Replication | File | 2008 | |
| OpenAFS | C | IBM Public License | Virtual file system, Installable File System | | | Replication | Volume | 2000 | |
| OpenIO | C | AGPLv3 / LGPLv3 | Native (Python, C, Java), HTTP/REST, S3, Swift, FUSE (POSIX, NFS, SMB, FTP) | Yes | | Pluggable erasure codes | Object | 2015 | 0.5 |
| Quantcast File System | C | Apache License 2.0 | C++ client, FUSE (C++ server: MetaServer and ChunkServer are both in C++) | master | No | Reed-Solomon | File | 2012 | |
| RozoFS | C, Python | GPLv2 | FUSE, SMB, NFS, key/value | Yes | | Mojette | Volume | 2011 | |
| Tahoe-LAFS | Python | GNU GPL | HTTP (browser or CLI), SFTP, FTP, FUSE via SSHFS, pyfilesystem | | | Reed-Solomon | File | 2007 | |
| XtreemFS | Java, C++ | BSD License | libxtreemfs (Java, C++), FUSE | | | Replication | File | 2009 | |

### Proprietary

| Client | Written in | License | Access API |
| BeeGFS | C / C++ | FRAUNHOFER FS (FhGFS) EULA, GPLv2 client | POSIX |
| ObjectiveFS | C | Proprietary | POSIX, FUSE |
| Spectrum Scale (GPFS) | C, C++ | Proprietary | POSIX, NFS, SMB, Swift, S3, HDFS |
| MapR-FS | C, C++ | Proprietary | POSIX, NFS, FUSE, S3, HDFS, CLI |
| Isilon OneFS | C/C++ | Proprietary | POSIX, NFS, SMB/CIFS, HDFS, HTTP, FTP, SWIFT Object, CLI, Rest API |
| Qumulo | C/C++ | Proprietary | POSIX, NFS, SMB/CIFS, CLI, S3, Rest API |
| Scality | C | Proprietary | FUSE, NFS, REST, AWS S3 |

## Remote access

| Name | Run by | Access API |
| Amazon S3 | Amazon.com | HTTP (REST/SOAP) |
| Google Cloud Storage | Google | HTTP (REST) |
| SWIFT (part of OpenStack) | Rackspace, Hewlett-Packard, others | HTTP (REST) |
| Microsoft Azure | Microsoft | HTTP (REST) |
| IBM Cloud Object Storage | IBM (formerly Cleversafe) | HTTP (REST) |

## Comparison

Some researchers have made a functional and experimental analysis of several distributed file systems including HDFS, Ceph, Gluster, Lustre and old (1.6.x) version of MooseFS, although this document is from 2013 and a lot of information are outdated (e.g. MooseFS had no HA for Metadata Server at that time).
The cloud based remote distributed storage from major vendors have different APIs and different consistency models.