[[PageOutline]]
+Mostly written by Donald Guy, [[BR]]
+drawn from a variety of sources. [[BR]]
+Credit goes to them, blame goes to him.
+
= What is AFS? =
The '''Andrew File System''' or '''AFS''', is a distributed network file system invented at [http://www.cmu.edu/index.shtml Carnegie Mellon University] as part of Project Andrew (approximately their equivalent of MIT's Project Athena). More importantly, it is the file system used to store most files on Athena today. This includes your personal home directory, your dorm site, and probably some of the software you run, if you ever use clusters. (Though all user directories were migrated from NFS in the summer of 1992, some files probably still remain on NFS and, of course, various file systems are used on personal computers and servers).
= Some MIT/AFS terminology =
'''locker'''::
- For practical purposes, a folder. Probably the what you'll care about most of the time. Technically any directory mountable under /mit, regardless of how its stored. Today, most lockers (possibly all) lockers are stored in AFS.
+ For practical purposes, a folder. Probably the what you'll care about most of the time. Technically any directory mountable under /mit, regardless of how its stored. Today, most lockers lockers are stored in AFS.
'''tokens'''::
Essentially proof to the AFS servers that you are who you say you are, thus allowing you to access files you are supposed to. Analogous to Kerberos tickets.
=== From Athena ===
-On Athena you can access a locker either as its full AFS path, if you know it ( e.g. /afs/athena.mit.edu/course/6/6.01 ) or under {{{/mit}}} if it is "attached." Yet a third way is to use tilde expansion and simply {{{ cd ~<locker> }}} (e.g. {{{cd ~6.01}}}) which will take you to the full path. Often, however, you want to attach lockers because it is easier to refer to them outside of the shell (in a script, for example) and software is set-up to run with a path under {{{/mit}}}. There are a few ways to attach a locker:
+On Athena you can access a locker either as its full AFS path, if you know it ( e.g. /afs/athena.mit.edu/course/6/6.01 ) or under {{{/mit}}} if it is "attached." Yet a third way is to use tilde expansion and simply {{{ cd ~~<locker> }}} (e.g. {{{cd ~~6.01}}}) which will take you to the full path. Often, however, you want to attach lockers because it is easier to refer to them outside of the shell (in a script, for example) and software is set-up to run with a path under {{{/mit}}}. There are a few ways to attach a locker:
* If you are running on a [http://debathena.mit.edu Debathena] machine, such as [http://linerva.mit.edu linerva.mit.edu], then simply {{{cd /mit/<locker>}}} and it will be auto-attached.
* If you are on another Athena machine and don't want to run software out of the locker, than simply type {{{attach <locker>}}} and then `cd` to it.
=== From the Web ===
-Generally any locker that you would access on Athena as {{{/mit/<locker>}}} is accessible on the web as {{{{http://web.mit.edu/<locker>}}}. For example, the barnowl locker is at [http://web.mit.edu/barnowl]. As you can see, if there is no index.html (see below), the files in the directory are listed. By default, however, none of the contents are readable except in the `www` and `Public` folders.
+Generally any locker that you would access on Athena as {{{/mit/<locker>}}} is accessible on the web as {{{{http://web.mit.edu/<locker>}}}. For example, the barnowl locker is at [http://web.mit.edu/barnowl}. As you can see, if there is no index.html (see below), the files in the directory are listed. By default, however, none of the contents are readable except in the `www` and `Public` folders.
Also, you may access something in one of the MIT AFS cells by taking its full AFS path after web.mit.edu ([http://web.mit.edu/afs/athena.mit.edu/activity/c/chess-club]). (That link also shows that if you have a text file named README readable, as a link to Public/README for example, its contents will be displayed below the directory listing).
and then doing a {{{ln -s www/redirect.html index.html}}} in the top level of the locker. Alternatively you can link index.html to a blank file in your `Public` or `www` (you can't simply it in the top level because its not readable there, this will result in a 403 Forbidden error).
-===It was around 6am on a Sunday morning and suddenly I couldn't access my files ===
+=== It was around 6am on a Sunday morning and suddenly I couldn't access my files ===
Yea, IS&T restarts the AFS servers weekly around 6am.
-===It isn't Sunday and I can't get to my files ===
+=== It isn't Sunday and I can't get to my files ===
There may be a non-scheduled AFS outage. Check [http://3down.mit.edu 3down], hopefully it will be back up soon :-(.
= Advanced Tasks =
While it is easily possible to make an AFS group for yourself, it is harder to get a new locker. If you want a locker for something official like a student group or a piece of software, send an email to [mailto:accounts@mit.edu] explaining what you need it for and someone at IS&T will let you know. If you feel it is something less official or you would just rather consider it a SIPB project (perhaps get other SIPB people involved) send an email to [mailto:sipb-afsreq@mit.edu] instead. In either case, if a mount point under {{{/mit}}} fails to get set up for you, let [mailto:hesreq@mit.edu] know.
= See Also =
-SIPB's older guide, [http://stuff.mit.edu/afs/sipb.mit.edu/project/doc/afs/html/afs-new.html Inessential AFS]
+SIPB's older guide, [http://stuff.mit.edu/afs/sipb.mit.edu/project/doc/afs/html/afs-new.html Inessential AFS] [[BR]]
OpenAFS documentation at [http://www.openafs.org/]
sipb-www / wiki.git / blobdiff