Information about Minix1.hampshire.edu

revised 17 February 2005

This system runs Minix, a Unix clone developed by Andrew Tanenbaum. Early versions of Minix were similar to the ATT Unix 7th Edition in its operation, although quite different internally. This system came on line in April 1994, running Minix 1.5. It has been upgraded as newer versions of Minix became available. Minix version 2.0 was released in October, 1996, and is a modern POSIX-compliant version with network support. This server is now running Minix 2.0.2, released in December 1998. You are accessing this information via the latest version of the Minix http server.

This system has several purposes. Initially it was intended only as a testbed for developing and testing network tools using Minix. Several developers of Minix software have user accounts here for this purpose. As the robustness of Minix's network programs has been proved the system has become a server, providing a home to several web pages, including Al Woodhull's Minix home page, which includes the current official Minix FAQ.

Originally files were served by FTP, but in early 2005 a decision was made to discontinue anonymous FTP access. All files can still be downloaded using the http protocol, however. All Minix 2.0.* distributions are available (except for PostScript man files), as well as an assortment of contributed programs. Finally, a number of people in different parts of the world have user accounts here for various purposes. It can, for instance, be useful to a system administrator to have a login account in another country in order to test routing and name service.

System configuration:

Hardware: Minix requires only modest hardware. Minix1 was originally set up on a 386 with 2M of RAM in early 1994. In February 1997 it was upgraded to a 33Mhz 486 with 8M of RAM. In May 2000 this was replaced with a 100 Mhz Pentium system with 32M of RAM. There is approximately 2G of hard disk space available, on two drives. The network connection is via an NE2000-clone ethernet adapter to the subnet of the School of Natural Science at Hampshire College. For performance and data security the root file system is on an 8M RAM disk. Additional disk space is used for backup.

Software: Minix 2.0.2, 32-bit (i386) is installed on this system. The Minix OS is compiled with a 1M file system block cache. The operating system supports networking and more users than the standard configuration. You can browse the Minix source code as used on this site.

Some Notes on Performance

As of January 2001 Minix 2.0 has been running on this system for about four years. It has proved to be quite robust. This system is on line 24 hours a day, 7 days a week. In a typical day there are several hundred, sometimes over 1000, accesses to the system over the Internet. Click here to see statistics on recent connections to this site.

Most system administration is done remotely. For six months in 1997 the system administrator was working in another country. There were only two occasions during that period when somebody at Hampshire College had to be asked to do an on-site reset of the system.

There are a few steps that are taken to improve the performance and increase the robustness of the system.

• The root file system is kept on a RAM disk, and the master copy of the root file system is normally not mounted, affording some measure of security for its files.
• Some binaries that are installed in /usr/bin on a standard Minix system are copied to /bin on the RAM-disk root device. In particular, network servers are kept here, for fast loading without disk access.
• Important events, such as reboots, result in automatic sending of an e-mail message to the system administrator. A number of periodically run scripts monitor other aspects of performance and also report by e-mail.

Before upgrading to Minix 2.0.2 in May 2000 automatic reboots were scheduled periodically to be sure any stuck processes were removed and the system was restored to normal operation. This is no longer considered necessary, and uptimes between reboots have been months at a time since the upgrade.