File System Organization

The Undergraduate Computing Laboratory File System is spread over the various server and client machines. Generally, the same information is accessible under both Windows and FreeBSD, though the method of access is somewhat different. Below is a brief description of what there is and how to access it. The fastest way to get an idea of ``what is out there'' is to type ``df'' under FreeBSD. This will list all the currently mounted filesystem volumes, together with some information about each one. Typical output from this command might look as follows:
Filesystem               1K-blocks     Used    Avail Capacity  Mounted on
root_device                   4847     4702     -242   105%    /
bfs1:/export               1498351   884229   494254    64%    /server
procfs                           4        4        0   100%    /proc
/wd0s4e                      24351     1813    20590     8%    /impure
/dev/wd0s4f                1043165   753558   206154    79%    /pure
/dev/wd0s4g                  97454        1    89657     0%    /scratch
raid:/raid                32546784  8301879 21641163    28%    /raid
raid2:/raid2              16172359  5019235  9859336    34%    /raid2
mailhost:/local/var/mail    875823   208388   597370    26%    /impure/var/mail

The root_device, /wd0s4e, /dev/wd0s4f, and /dev/wd0s4g filesystems are client workstation file systems located on the workstation hard drive. The raid:/raid, and raid2:/raid2 filesystems are user file systems located on the file server machines raid and raid2. The bfs1:/export and mailhost:/local/var/mail are other server file systems located on the file server machines bfs1 and mailhost.

Client Workstation File Systems

The hard disk on each client is treated as a volatile storage area that is used to cache commonly used data. As part of the FreeBSD boot procedure, the disk is checked and reloaded, if necessary, to make sure that this data is up-to-date and has not been corrupted. The root_device filesystem is mounted on the root directory ``/'', and is read-only. The /wd0s4e filesystem is mounted on the directory ``/impure''. This is a read/write area that is used by the system to record the state of various processes that are always running. The /dev/wd0s4f filesystem is mounted on the directory ``/pure''. This is a read-only area that serves as a large cache of commonly used data and executables. All three of these filesystems are FreeBSD-specific and are not accessible from Windows. The suggested method for getting information between Windows and FreeBSD is by writing it in your home directory, which can be mounted after you boot up Windows, as described here.

User File Systems

User files are stored on one of the following two filesystem volumes: raid:/raid, raid2:/raid2. These volumes are accessible from client workstations running FreeBSD by using the paths: /raid, /raid2. The same volumes can be accessed from Windows, as the network shares raid and raid2. When you attempt to connect to these shares, you will be asked for and ID and password. Use your Unix ID and password for this. More information about running Windows can be found here.

Other Server File Systems

The bfs1:/export and bfs2:/export filesystems contains system binaries for FreeBSD. Client workstations mount this directory on the ``/server'' directory. Most of this data is cached on the client workstations, and the master copy is only referenced when the disk needs to be reloaded.

The mailhost:/local/var/mail holds everyone's mailbox. It is mounted on each client workstation to permit users to access and manipulate their mail from any client machine.

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