Introduction

This is really only a quick sketch of a complete FAQ. Hopefull, however, I'll be able to cover the necessary basics.

Here again I would like to stress how to get help. For general Unix questions, email unixhelp@psu.edu. For help regarding software in the lab, or hardware problems in the 316 Hammond unix lab, mail ptpadmin@psu.edu.

• Logging in

  • How do I log in?
  • User ID? Access account?
  • Changing you password.
  • Logging in Remotely.
  
  

• Accounts

  • Getting Accounts if you are a student.
  • Requesting Accounts if you are a professor.
  
  

• Mail

  • Reading Mail
  • Reading access acount (POP) mail.
  
  

• Printing

  • What's it gonna cost me?
  
  

• Disk Drives

  • Reading from the disk drive.
  • Reading/Writing DOS Formatted diskettes.
  
  

• AFS

  • AFS What is it? Why do I care?
  • How do I let other people access my files?
  
  

Logging In

Question:

How do I log in?

Answer:

If you have an account on the machine, (see: Getting Accounts) you can simply log in by typeing in your current access acount user ID and password.

See: User ID? Access account?

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Question:

User ID? Access account?

Answer:

Every student at Penn State gets an access acount, along with a ph entry and a POP account for mail. (see Reading Mail for information about POP and ph) You'll notice that your user ID on the hammond systems is in fact the same that you have for your access account. This makes it easier for us, because we use the same authentication system in the lab that we do for, say, logging into the modem lines. (It's called Kerberos, check out the AFS Tutorial for a little more information.)

So if you changed you access account password, the password on the machines in hammond will change as well.

See: Changing your password

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Question:

What's the deal with changing my password?

Answer:

We use the kerberos system of authenication. (See: AFS) Changing your password is the same as changing your access acount password. There are a number of ways to do this. Normally, you would just telnet to access.psu.edu, dial into the modems with a terminal emulator, and change your password there. However, there is an easier way to do this on the hammond machine.

The kpasswd command. For the average user (ie: not administrator) this will function exactly the same way as the passwd command. First, type in your old access acount password. The the new password twice. (To make sure you typed in it correctly.) Then, the password is changed.

It then it also changed for dialing in, or using the other public Mac/PC labs. If you have any scripts wt home ith the password it in, (like dial up scripts, or PPP connection script) don't forget to change them.

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Question:

How do I log in remotely?

Answer:

It is possible to log on remotely, using the telnet command, to the lab machines in Hammond. The lab machines are the machine in the back of the room, namely h20 - h29. These are the only machines that allow remote access. Pick a number at random, telnet to it's address. (ie: telnet h27.ptph.psu.edu)

Remote login is not allowed in the classroom machines, namely h30-h60. (You're welcome to try, but face it, it ain't gonna happen.) This is done because at times classes are taught in this room, and we don't want to steal time from people using the machines.

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Accounts

Question:

How do I get an account on the ptph machines?

Answer:

You must have your faculty advisor contact the CAC Accounts Department accounts@psu.edu, 5-4772 and fill out an Application for Academic Computing Account Services form for the class. On the account request form, you should select UNIX Cluster as the account type.

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Question:

How do I request accounts for either of the IBM SUR classrooms located in Hammond and Osmond?

Answer:

You must contact the CAC Accounts Department accounts@psu.edu, 5-4772 and fill out an Application for Academic Computing Account Services form for the class. The students receive I (Instructional) accounts which get dropped at the end of each semester. If you plan on using the labs on a regular basis, you should request a C (class) or U (research) account for the lab as well as it only needs to be renewed once a year. On the account request form, you should select UNIX Cluster as the account type.

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Mail

Question:

How do I read e-mail from the hammond lab machines?

Answer:

The ptph lab has no mail server of it's own, and as such you can't mail to any of the machines directly.

Now, you can read mail and send mail from each of the machines. When you send mail from any of the machines, it changes your address from, say, chilly@h42.ptph.psu.edu to chilly@psu.edu. This means that all mail sent from the labs will look like it came from your access account, so all reply sent to you will go to you access acount mail box.

This mail box is normally userid@email.psu.edu, (ie: chilly@email.psu.edu for me) the POP server. When you get an access acount, it is automatically set to receive mail with the POP server, so unless you specifically changed it, you will be getting mail from the POP server.

If you want to check where your mail is going, type "ph -r $USER" at you prompt. The email: field is where mail sent to "userid@psu.edu" is being forwarded to. If this ends with email.psu.edu, the mail is going to the POP server.

If you want to read mail from the ptph machine (and you can, really, it's fine) check out reading pop mail.

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Question:

How do I read POP mail, (access acount mail) from the ptph lab?

Answer:

If you are logged in on one of the machines in the lab, there should be a window that looks remarkably like this on the bottom right.

Click the mouse button there. A little dialog will come up, asking for your POP mail (access acount) password. Click in the little box, and type it in. (Characters will not echo, the # will instead. This is done on purpose.) Press OK. Then, either a window telling you that you password is incorrect will show up, or a window with the pine editor will start up for you automatically. When you quit pine, the window will close.

What this script does, is to call the programm "popclient" to get your mail from the POP server. It deletes it from the server to save CAC resources, and copies it to your afs directory. Therefor, if you try and read your mail with Eudora from home, then all messages that you recieved at the lab will not appear. (There is a way to let the messages stay on the server, but we don't like people doing this per se, so I'm not going to tell you how to do it. Figure it out yourself if it's so important.)

Unlike some other UNIX machines, mail on the ptph lab is not stored in /usr/spool/mail or /var/spool/mail, it's stored in everyone home directory, in the subdirector access_mail. So, the enviromental MAIL variable is set to $HOME/access_mail/$USER, instead of /usr/spool/mail/$USER. So DO NOT DELETE THE access_mail DIRECTORY, YOU WILL LOSE YOUR MAIL.

Thank you.

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Printing

Question:

Printing - how much is it going to cost me?

Answer:

Printing from the hammond lab now works exactly like it does in any other CAC lab at this point. Much like a crack dealer hanging around middle schools, the first 60 pages are free, then we make you pay. The cost is 10 cents per page, which will be billed through the bursar office.

This is idenitical to all other CAC supported labs. You have to authorize printing through any of the signature stations. (There is one in Willard, and there is one in the accounting office in the Computer Building.)

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Printing

Question:

How do I read data from the disk drive?

Answer:

If you have a floppy diskette with raw data on it, or something like a tar file or a cpio achive, the device of the floppy is /dev/df0. (If you are trying to get a file off of a DOS formatted diskette, check out reading/writing DOS Formatted diskettes.)

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Question:

How do I get data to and from DOS diskettes?

Answer:

dosread, dosdir, doswrite, dosdel, dosformat

If you know MS-DOS or it's clones, these commands are fairly self-explanitory. For the gory details, do a man whatever on them. (Don't look at me, I use a real computer at home...) Remember, if you are copying text file's back and forth, which you probably are, use the -a option. This will convert DOS' stupid cr/lf combination to just lf, or vica-versa depending which way you are going. The -a option will also place a cntl-Z at the end of the file if you are copying it onto a disk.

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AFS

Question:

AFS? What is it? Why do I care?

Answer:

AFS is the logically follow on the NFS. Basically, it allows you to access the same file on multiple machine seemlessly. You should care about this because all of your home directories are in AFS. The Numerically Intensive Computing group at the CAC has a good AFS tutorial which you should check out.

Note: when you log on, you are automatically given a token in the psu.edu cell, which is where your home directories are.

Or, for those who really want to know the answer to this question, the AFS FAQ at transarc.com will explain everything you want to know.

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Question:

How do I let other people access my files?

Answer:

Every account on the hammond cluster has their home directory in AFS. While this simplifies sharing files across machines, it completely overrides unix file permissions.

unix does permissions by file, AFS does permission by directory. The only unix permission bit that matters in a file on AFS is the execute bit. ie: you can only run file which are marked as executable, not matter where you are running them from.

To list the ACL (Access Control Lists) for a directory, type :
fs la directory name
For example, typing fs la ~chilly should give you :

Access list for /afs/psu.edu/users1/chilly is
Normal rights:
  system:administrators rlidwka
  system:anyuser l
  chilly rlidwka

This lists out the ACLs for my home directory. system:administrators and chilly would would pretty much leave alone. (Obviously, if you listed out your home directory, than chilly would be replaced with your user ID. Don't muck with it : you probably want to keep access to your files...)

(Check out the explanation of ACL in the FAQ from transarc.)

Now, because I set up a web page for myself, I added the system:anyuser acl. I gave it the l priviledge, meaning that I'm allowing anyone on the planet to access my directory -- not reading any of the files in it, but they can cd into it and list what I have inside. system:anyuser means anyone in AFS. system:authuser means only people with tokens in our cell, namely psu.edu. So if you only want people who have accounts on the machines in hammond to access your files, than use system:authuser. Unfortunatly, we are running the web server without a token, so if you want to have a home page, you need to give system:anyuser list access.

Now, if you want to create a web page, you will also need to make your public_html directory world accessable and world readable. This can be done by setting the ACL to rl, or read, which is a macro for rl. Quick cookbook for setting the permissions on your directory:

• Making a directory acessable, so people can access directories further along, down the path:
  fs sa ~ l
  The second argument, ~, is the directory to set. In this case, your home directory.
• Make a directory accessable and readable:
  fs sa ~/public_html read
  read is a macro for rl

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