Ask SIPB
This week, we talk about a few miscellaneous things that might make your life easier.
Can I connect to Athena remotely?
Yes — IS&T maintains a set of official dialup servers, and SIPB maintains the Linux dialup linux.mit.edu. There are also many private dialup machines, run by various groups, that they maintain for their members. The name “dialup server” is a historical artifact from the days when there were large banks of modems, and you had to dial-in over a phone line to get a connection.
To connect to a dialup, you’ll need to use the ssh (Secure Shell) protocol, which comes in various flavors. The simplest ones will just give you a text terminal, but you can also use X forwarding to use graphical applications with the X Window System.
The official dialup machines are Sun Solaris servers, which sometimes are slow to respond and do not support Linux-only software. If you want to use a faster Linux server, SIPB maintains linux.mit.edu (“Linerva”), a Linux dialup that runs Debathena (another SIPB project; see debathena.mit.edu for more details). If you’re using SecureCRT, you can open the “Athena” connection’s properties and change the server to linux.mit.edu.
From a Windows machine, you can download SecureCRT from http://web.mit.edu/software/. This will just give you a text console; to get graphical capabilities, you should download X-Win32 from the same site.
From a Mac or Linux machine, you can connect by opening a terminal and typing ssh USERNAME@linux.mit.edu. To run graphical programs, replace ssh with ssh -Y. On a Mac, Terminal.app is in /Applications/Utilities, as is X11.app, needed for graphical programs. If you don’t have X11, you can install it from the Mac OS X installation discs.
You can also visit http://athena.dialup.mit.edu/ from a web browser with Java; however, many people find the Java applet limiting — for example, it does not support copying and pasting.
What is a VPN and why would I use it?
ISPs will often set up port filtering and other things for network security purposes. (Incidentally, MIT does not.) Unfortunately, this can lead to problems running some applications that use the network, and there are some MIT-specific applications that check for MIT-specific IP addresses, such as Student MATLAB. A Virtual Private Network (VPN) helps you use MIT computing services, effectively putting your computer on MITnet even when your connectivity is provided by some other ISP, and thus bypassing the blocks that interfere with applications. You can enable the VPN when you need it and disable it when you don’t.
You only need the VPN if you are connecting from off-campus; dorm and FSILG residents are already on MITnet. The MIT VPN Client is available for Linux, Macintosh, and Windows. You can download the VPN software from http://web.mit.edu/ist/services/network/vpn.html. Be sure to read the “Known Issues at MIT” page for your platform.
How do I set up my personal computer to print to Athena cluster printers?
There are a couple of ways to set this up. Older students may be familiar with KLP/KLPR, applications that allow you to authenticate with Kerberos to cluster printers. However, the printers in public Athena clusters no longer require Kerberos authentication.
If you’re using Debathena on your Ubuntu or Debian GNU/Linux machine, printing to cluster printers is already set up for you! Otherwise, to set up printing to a cluster printer, you’ll need to know a couple things about that printer first — log in to Athena, and run the command hesinfo printername pcap. If you need the name of a printer, try the command cview printers. The output will look something like:
athena% hesinfo ajax pcap
ajax:rp=ajax:rm=PAPER-PUSHER.MIT.EDU:ka#0:mc#0:auth=kerberos5:xn:
From this, note the “rp” (ajax) and “rm” (paper-pusher.mit.edu) values, which name the print queue and server, respectively. Now go to your computer’s Add Printer dialog, and choose the option to create an “LPR” or “LPD” printer. (On Windows, this is considered a type of local printer.) Enter the print queue and print server names when prompted. If you need detailed instructions, see one of these pages:
• Windows XP: http://itinfo.mit.edu/article.php?id=6376
• Windows Vista: http://itinfo.mit.edu/article.php?id=8492
• Mac OS X: http://itinfo.mit.edu/article.php?id=8246
That’s hard. And I have to do this again for each printer?
Yeah. Another option is to use quickprint.mit.edu. This website, created by a SIPB member, allows you to upload a PDF, PostScript, or plain-text document and select (from a map!) a cluster to print it to. Moreover, Windows XP or Vista users can install quickprint as a network printer, so they can print from any application. When you print a document, it will be uploaded to the quickprint website and stored there for up to a week, so you can choose when and where to print it.
I want to set up a blog or a wiki. Can I do this easily?
Certainly. The popular SIPB project scripts.mit.edu provides hosting for CGI scripts in a number of languages (PHP, Python, Ruby, sh, etc.); a sister project, sql.mit.edu provides MySQL databases that run the backend of popular web applications. You can sign up your own locker, or the locker of a group that you maintain, for the scripts service. You can also ask for a somename.mit.edu hostname, instead of the default lockername.scripts.mit.edu. Visit http://scripts.mit.edu/ for instructions on how to get started. Running
athena% add scripts
athena% scripts
will bring up a menu of software that can be automatically installed.
How can I listen to music on demand?
SIPB’s LAMP service (the Library Access to Music Project) allows you to listen to a large collection of CDs via MIT cable TV. All you need to do is visit http://lamp.mit.edu/ (you’ll need your MIT personal certificate), search for the music you want to listen to, and tune to the appropriate channel. Unlike P2P music sharing, LAMP’s design, which uses MIT’s analog music license, is guaranteed not to get you into legal trouble.
To ask us a question, send e-mail to sipb@mit.edu. We’ll try to answer you quickly, and we can address your question in our next column. You can also stop by our office in W20-557 or call us at x3-7788 if you need help. Copies of each column and pointers to additional information are posted on our website: http://www.mit.edu/~asksipb/