How a K-12 school system is using Linux to supply a myriad of stable network services to its students and staff.
The Millbury Public Schools make up a small school district of just over 1800 students, located in the heart of Massachusetts. We provide state-of-the-art computing services to our staff and students as a tool for learning and research. Linux holds a distinguished position on our network and supplies many of the network services required by our users. I hope this article will persuade educators to think of Linux as a viable and even preferred alternative to conventionally marketed products.
Like most public school districts, our computer technology was exclusively Macintosh-based and required a lot of effort and attention to keep it working and usable. After some lobbying on my part, an endeavor was made to bring our technology resources in line with what was in use in the “real world”. The argument I used was not that it was a nightmare supporting a hundred Macintoshes (it was), but that as an educational system we should be educating our students on computer systems they would be more likely to find in the college and business world. The fact that Apple Computer has been floundering in the marketplace didn't hurt my argument.
Coinciding with our migration to an Intel platform was the availability of a generous grant made by the Commonwealth of Massachusetts, specifically earmarked toward networking the state's school systems. This allowed us to set up a district-wide network and network services that rival those of many businesses. Between the state's grant and our supportive school committee, which approved our budget for new PCs, we had sufficient funds to do the job right.
Our network is arranged into 10Base-T workgroups tied into a central Ethernet switch (collapsed backbone configuration). This switch is segmented into two networks—administrative and student—providing our first level of network security. The servers are connected via 100Base-T to the switch. This arrangement allows us to share network resources without sharing bandwidth. The central switch creates a smaller collision domain for each workgroup and keeps traffic on the backbone to a minimum.
The client machines, which run Windows 95, are Pentium 166MHz clones with 32MB RAM and 2GB of disk space. We also have a number of Power Macintoshes remaining in some of our labs. Our three servers consist of Pentium Pro 200MHz with 128MB RAM and 4GB of SCSI disk space (soon to be 9+GB). One of these servers is a Windows NT machine used for applications serving and the other two are Red Hat Linux-driven for everything else.
The two Linux servers are set up to supply file and Internet services to our district. Our first box (http:www.millbury.k12.ma.us/) is set up as our WWW, FTP, e-mail and DNS server and resides on the DMZ of our Sonic Interpol firewall that is in turn connected to an ISDN router. This firewall/router combination would also have been Linux except for the fact that the Sonic Interpol offers content filtering. This helps us protect students from inappropriate web sites on the Internet—an essential device when many curious kids are around.
The second Linux box, located behind the firewall, was just recently “saved” from being an NT machine and operates as a proxy/cache server, intranet server, file server and has a number of other small duties. Luckily, NT was so disappointing in performance and rather unstable that it was “born again” as a Linux server. I have not regretted it.
Since both servers run Samba, I can map drives on the Win95 clients so that the transfer of files to our web site is a breeze. File sharing is also handled this way. Few users actually realize they are saving to a network drive, due to the speed of the transfer.
As we still have a few remaining Macintoshes on our network, we could supply AppleTalk services with Linux. We do not at this time, because these Macintoshes are located in the lower grade levels and our youngest students do not need most network services. It would be very easy to set up if it became necessary. Many of our network services are platform independent.
Linux running the Squid proxy server (http:squid.nlanr.net/) has increased the perceived bandwidth of our ISDN by a huge amount. It is also considerably faster than when it was running NT and Netscape's Proxy Server. Approximately 50-60% of all our web page requests are serviced by our in-house proxy server. The increase in speed resulting in pages coming through from the proxy at Ethernet speed rather than from the web site at Internet speed has simply delighted my users. I've found that this service has made the biggest difference on our network. I almost never hear a complaint about the Internet being slow.
Samba (http:samba.anu.edu.au/samba/) is a terrific program, and once you get used to setting up its configuration file, it is a charm to use. Setting up users in Linux is more desirable for me than it is with NT. That, coupled with the lack of additional costs for NT client licenses, makes Linux all the more attractive. This cost savings is enough to help pay for staff training in beginning UNIX system administration.
This brings me to another point. Nearly all schools operate under tight fiscal constraints. Linux offers a way to develop technology without dipping too deeply into the shallow school budget. Linux even recycles older hardware that can be obtained through donations from local companies.
A side effect of all this Linux use is a number of students have actually become interested in Linux and are setting up their own boxes at home. One of our technology specialists (a former Macintosh user) has also fallen in love with the command line after seeing me use the power of TELNET to add users, check my e-mail and reconfigure something on the box.
Now that I have firmly entrenched Linux into our network, I plan on further purges of Windows NT from our domain. We will be purchasing additional servers for our workgroups and offices next year, and where application servers are not required, Linux will be installed.
I also hope to recruit more students and introduce them to Linux. Enlisting a new generation of Linux enthusiasts will only help drive Linux more firmly into the future.
I am very grateful to the whole Linux community for their excellent software. A big thank you is also sent to the Samba team for their labor in helping me rid our computers of NT wherever possible. I would also like to applaud the Squid developers for a top-notch product.
I would like to hear from anyone who has ideas on how to make Linux even more attractive and useful in a school environment. I would also be happy to share my experiences with anyone thinking of implementing Linux in their school.