Note: The FAQ is an evolving document. Please help to make it better. If you have any additions, suggestions or corrections, please mail Zube.
Where can I find the latest copy of this FAQ?
What resources are available?
Who may use the PRIMES computers?
How does one obtain a PRIMES account?
How do I change my password?
Where are all my math/stat unix/pc files?
What can I run on the PRIMES machines?
How many simultaneous jobs can I run on the linux servers?
What's the story with Matlab?
ssh/slogin/scp/sftp/putty/winscp to the unix machines doesn't
work. How can I fix this?
Why are PC logins so slow? What can I do about it?
How do I lose my account?
Patches and reboots.
Is my home directory backed up?
Will you install program X if I ask nicely?
What is the best way to report a problem?
Why are you (Zube) such a jerk?
Acknowledgments of Thanks.
Q: Where can I find the latest copy of this FAQ?
A: The PRIMES Computing FAQ is always here. That's http://www.math.colostate.edu/FAQ/primes.html if you are reading this on paper.
Q: What resources are available?
A: The PRIMES computing project consists of two parts: a Windows PC lab and two Linux compute servers. The PC lab is in Weber 223A. It contains 11 single-processor 3.0 ghz Pentium PCs with 2 gig of memory running Windows XP as well as two printers and a laptop on the front lectern. The compute servers are available for ssh remote login as well as X access from the PCs. Both servers are dual-Xeon 3.0 ghz machines with 4 gig of memory. They are pepper.math.colostate.edu and spectar.math.colostate.edu.
The PRIMES computing resources are, in many respects, experimental. The design approach is a bit different than previous labs (details upon request) and therefore you may uncover unexpected errors. Mail Zube if you find something odd, but please read the reporting errors section below before sending off your email.
Q: Who may use the PRIMES computers?
A: Anyone associated with a PRIMES class as well as those working on PRIMES research may ask for an account. However, the final decision about who is permitted to have an account rests with the co-directors, Richard Davis and Don Estep. "class" accounts, whether they are given to individuals or to a group, will be removed when the class has finished.
The PRIMES classroom itself is available on a limited basis for specialized graduate courses. Contact Don Estep for further information.
To find out more details about obtaining access to the PRIMES compute servers, please read the Access to PRIMES Compute Servers page.
Q: How does one obtain a PRIMES
account?
A: For most student or class accounts, your professor will be the person to talk to. S/he will contact me and I'll set up the accounts. For anyone else, please contact Richard Davis or Don Estep (or, if I know you, me directly).
Some things you may wish to keep in mind:
Q: How do I change my password?
A: In short, you can't. One reason is the system configuration and the other is people's desire to use simple passwords. I try to create passwords that are long, but not so silly that memorization is impossible. Sometimes I don't get the balance right, but most of the time people are just not used to using a good password.
If you believe your password is ridiculous, send me an email. We'll meet somewhere and you can show it to me. If it is ridiculous, I'll change it to something a bit easier. But you can't have squid1 or anything resembling it as a password.
Q: Where are all my math/stat unix/PC files?
A: This entry is for Math and Stat users only.
The PRIMES computers are, by design, separate from the rest of the world. On the PCs, you should be able to map your math/stat unix/pc files in the normal way (details soon; most of you already know how via explorer). On the unix side, however, you will have to shuttle files back and forth using scp or sftp. The math and stat unix home directories will not be mounted on the PRIMES computers.
Q: What can I run on the PRIMES machines?
A: The separate PRIMES world was meant for PRIMES teaching and research. We trust you to honor this rule without someone around to enforce it. As you might expect, there are consequences for breaking such a trust.
The PC machines possess a wide variety of software including most of what you would expect plus matlab, femlab, WinBugs, R, Splus, the full Acrobat package and Visual .NET. The Linux boxes have a full install of CentOS 4 update 6 plus a large amount of software in /usr/local.
Q: How many simultaneous jobs can I run on the linux servers?
A: First, some background information.
A machine with one processor can run one job flat out. It can run two jobs by switching back and forth between the jobs, etc. This is a gross simplification, but it will do. Another gross simplification is that if you have n processors, it can run n jobs flat out, 2n jobs by switching back and forth between the jobs, etc. But the switch isn't free; it costs time and resources to save one job and load the other one and then to save the other one and load the first one. This is especially true for memory-intensive programs.
Also note that the machines are shared resources.
The two lessons to take away from this are:
Both pepper and spectar are dual-processor machines. They are equal in both speed and memory. There is no reason to choose one over the other.
Keeping all this in mind, here are the rules:
How do you tell what's running? First, try the uptime command. The three numbers on the right will give you an idea of how many jobs are running. A load average of 0.00 means nothing is running, 1.xx means one job is running, etc. Also, using the top command is recommended, but please don't run top for extended periods of time as it uses a lot of CPU time. Use it to find out what's going on and then exit the program.
If you fail to follow the rules, any extra jobs running will be killed and you'll get nasty email. If you continue to fail to follow the rules, your account will be disabled.
Q: What's the story with Matlab?
A: PRIMES has two separate licenses for Matlab.
The Matlab license on the PCs is a classroom license, which means it can be used only for instructional/class use only. You cannot use it for any research or commercial use and you'll be reminded that it is a classroom license every time you open the program. The PC install includes the optimization, statistics and wavelet toolboxes.
The Matlab license on the linux boxes, however, can be used for research. Alas, it has no additional toolboxes.
Q: ssh/slogin/scp/sftp/putty/winscp to the unix machines doesn't work. How can I fix this?
A: Mail Zube. He will mail you back a document that will explain the problem and the solution.
Q: Why are PC logins so slow? What
can I do about it?
A: It's Symantec Anti-Virus 10.x that causes this. The 7.x version was fast; the 8.x version was slower, but usable. With the 10.x version, it may take minutes between the time you login and the time you can actually get work done. Symantec withdrew support for 8.x in Feb 2007, so, sadly, we are stuck with 10.x.
Here is how you can speed up the process for all future logins:
Unfortunately, the scan is generated for *each user*, so *each user* on each machine must do this. If you kill the scan on machine A, all future logins on machine A will be faster, but all future logins on machine B will still be slow (until you kill the scan on machine B, etc.).
You might thank your Lucky Stars that we are still using SAV 10.x. Its replacement is Symantec Endpoint Protection (SEP) and it's even slower. For the record, in the spring of 2008 I tried to move away from SAV/SEP to Avira Antivir, but this decision was blocked blocked by the central CSU IT support people (ACNS, Academic Computing and Networking Services). In my limited tests, Antivir was much faster than SAV/SEP as well as being less expensive, but it all fell on deaf ears.
A: You lose your account if you break any of the following rules, and no, I'm not kidding.
A: Yes, both the Linux boxes and the 12 PCs need patches and reboots every so often. How often depends on the severity of the problem. For normal patches and problems, everyone will get a fair bit of notice and I will (try to) wait until the long-running jobs are completed. However, in the case of a serious security problem, security comes first. I won't put the security of the network at risk just so your job can finish.
For the PCs, MS has started releasing patches the second Tuesday of every month. If PC patches are to be installed, they will be installed around that time. Many of the patches MS has released recently have been "critical," meaning "install it yesterday." Please plan accordingly.
For the Linux boxes, ssh and kernel upgrades are the two most common reasons for reboots. These may occur at any time, but they don't occur very often.
Q: Is my home directory backed up?
A: Yes. We back up all home directories in full every night. When the file systems get too big to do this, we'll go to an incremental-six-days, full-backup-one-day weekly schedule.
Q: Will you install program X if I ask nicely?
A: If it builds cleanly (or installs cleanly), will easily go into /usr/local (linux) or somewhere logical (PCs), has direct relevance to PRIMES work and doesn't need special privs or permissions, yes.
Q: What is the best way to report a problem?
A: In detail. All problem reports should contain the following information:
I can't print. HELP!!!!
I tried to do X, but it doesn't work.Here is a much better one:
I am unable to print from pr1 to the prlp1 printer. I logged in as I normally do, started Word and typed a document. I saved it, and then tried to print it. It never came out. I tried again, and it still didn't come out. Other people on other machines could print to ps, as I saw people picking up printouts. I haven't seen this problem before.
Also note that problems can be fixed only if I know about them. If you discover a problem, please report it.
Give yourself a pat on the back and a gold star if you read the following document, titled How To Ask Questions The Smart Way before reporting your first problem. While the above document is more about asking questions about software in forums and newsgroups, the general principles are useful just about anywhere. It also provides some insight into the techie mindset. It is time well-spent and will pay for itself many times over if you frequently interact with technical people.
Q: Why are you (Zube) such a jerk?
A: This is a fair question. I *am* a jerk, sometimes. As many people will attest, I am high-strung, have a short temper, have zero patience during stressful times and horror of horrors, I have even been known to swear out loud (gasp!!).
A large part of the problem is me. I do not play well with others (I sometimes run with scissors too) and I take things personally. I also cover a fair amount of ground between the Stat department, the Math department, the PRIMES lab and the Weber 205/206 lab, so my todo list is strictly non-decreasing. As you might imagine, this puts a huge premium on my time. I'm happiest when people value my time. Sending me email instead of asking me in person, skimming the FAQ before asking me a question, giving me weeks or days to do something rather than hours or minutes and especially, not breaking any of the rules listed in the "How do I lose my account?" section of this FAQ are all examples of understanding the value of my time. I am much less likely to be a jerk if you show me some courtesy.
In short, I care a lot about the computer systems and I'm busy. This can be a dangerous mixture and is one of the reasons I try to do as much as possible via email. In a more generous world, your system person would always be calm and rational. Sadly for both of us, that world is not this world. I know and understand my shortcomings and so should you. Thank you or else.
A: The PRIMES computer project is due to: