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Last edited: 12:11:16 pm on 10 March 2004 by salchicha.sico.local

!!! IBM afs v 3.6 || openAfs || Arla Project

Andrew FileSytem initially developped at Carnegie Mellow University ( CMU ), then by TransArc, then IBM. 
IBM forked the developpement tree in 2000 to give birth to OpenAfs, open-source, free and widely used (IPL licence). 
Recently, the ArlA project implements Afs Protocol under GPL licence. 
At this time the client-side is supported, the server-side is undergoing heavy developpement.

- AFS supports a maximum file size of 2 GB. 
- RPC based. 
- AFS supports a maximum volume size of 8 GB. In AFS version 3.5 and earlier, the limit is 2 GB. There is no limit on partition size other than the one imposed by the operating system. 
- less CPU usage than NFS 2-4 times less. definetly faster. great scalability. 
- RedHat 6.x & kernel 2.2.x, likely 2.4.x as well . 
- kerberos-like or kerberos-based security. 
- client caching , server replication 
- 'encrypted' file system & authentification... 
- a fileserver can be an authserver.. 
- used in many Universities ... designed to support 5,000-10,000 clients.

IBM: 
- NFS/AFS translator to keep volumes accessible by nono-afs client. 
- underliying rcp , rsh ? 
*http://oss.software.ibm.com/developerworks/opensource/afs/docs/html*(...) 
- rsh , inetd rcp, etc... remplacement... 
- tons of documentation

- Arla is a free implementation . client-side, working on server-side.

- Andrew II fs.

- Solaris client&amp;server 
- Linux Client&amp;server

!!! Coda 
 
Coda is a project also managed in CMU. it's aim is to be "better" than Afs in disconnected and weakly connected mode.

- from Afs2. 
- RPC based. 
- no compagny support .. 
- security -> weak build-in or kerberos patch. weak == XOR scrambling, but the challenge protocol is secure. 
- namespace, volume-sharing, not directory. 
- Coda is a forked of version of AFS that support disconnected and weakly connected mode better then AFS.

client point of view : 
- disconnected operations , caching ... 
- open() means copy() - based on file replication/caching. 
- small 10-200 Mo caching recommended. It seems that coda's users have larger cache area. 
- file to cache selectionnable ( hoarding ). 
- kernel support needed . very little patch, user-land application ( Venus ). 
- on update conflicts, user might need to resolve it manually..

server pov: 
- replication 
- consistency & transactions

- DFS sysadm seems to prefers Coda to Afs. 
- Coda seems not to be scalable : 
The documentation says the RVM metadata needs to be 4% of the total shared size and it needs to be backed by virtual memory for that same quantity.

- Linux client&amp;server 
- Solaris client , no server

!!! Ficus, Rumor & ROAR

- designed at UCLA for large scale DFS. 
- peer-to-peer structure. 
- optimistic consistency approach. 
- intelligent resolvation of update conflicts. 
- Rumor user-space implementation is beta stage. 
- intelligent hoarding. 
- Really accurate for mobile and disconnected DFS.

!!! Sistina GFS 5.1

- used for cluster's filesystem on fast LAN. 
- not useable on WAN networks.

!!! DAFS ( *http://www.dafscollaborative.org* )

- file sharing on SAN . Not for WAN .

!!! Sprite fs, part of SpriteOS

- no caching on write-shared files. 
- spritely NFS ? 
- less CPU-eater than NFS. 
- superseeded by afs.

!!! xFS - A Wide Area Mass Storage File System

- wwwos93.ps 
- multi hierarchical & caching 
- -> IBM XFS ? no network issue and LAN-applicated.

!!! Amoeba

- Amoeba is a DOS, so there is a DFS in it.. 
- micro-kernel and stuff..

!!! Odyssey

- application-aware. 
- need the application to be compliant.

!!! SFS @ sfs.net

- secure, encrypted... 
- basicaly , it's a encrypted NFS. 
- relies on nfsv3. 
- easy to install. 
- a lack of pam modules ?

!!! SFS @ *http://www.cs.auckland.ac.nz/~pgut001/sfs/* (...)

- secure, encrypted... 
- windows & Dos

!!! Lustre

- Another LAN-cluster dfs.

!!! LBFS - A Low-bandwidth Network File System

- Whole file Caching 
- NFS-like protocol. Over-NFS implementation. 
- Chunk SHA-1 calculation and comparaison. 
- Very _LOW_ bandwith utilisation. 
- SFS encryption support 
- Not for disconnected operations. 
- High disk load. 
- Need a Berkeley DB. 
- Probably high CPU load . 
- Less bandwith use than NFS,AFS... 
- Faster execution time. 
- Designed for Wan access. 
- 2 implementations 
-- a) with the xfs-arla client - caching, chunking but no authentification 
-- b) with the SFS client - authentification but no chunking, 
- small- freebsd nfs kernel patch, no linux patch .

!!! InterMezzo

- pretty much like Coda. 
- AFS -> COda -> Intermezzo 
- Aiming disconnected ops. 
- GPL 
- Module-Compilated in Redhat 7.3 
- More efficient than Coda is.

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