Accessible Computers

The Linux Open Lab computers are accessible from inside and outside the department. This allows students and faculty to remotely work on projects, access files, and check e-mail with programs such as pine and mutt. In order to get command line/shell access you will need to use SSH. This document contains information about how to download and use SSH.

Labs

The preferred method of connecting to a lab machine is to connect to schizo.cs.byu.edu. This is a DNS round-robin between six machines that have public IP addresses. If one machine happens to be down, your SSH client will try the next one.

You can connect to computers in the labs by their lab names. The following is a list of lab names, with each one corresponding to a room in the Talmage Building. If you connect to one of these names, you will go to a random computer in the lab. This method uses a one-to-many NAT. No matter how many times you connect to a given lab name, you will always be dropped on the same individual machine until you connect from a different IP address.

  • fruits (macs)
  • monsters
  • simpsons
  • weapons
  • instruments
  • sports

Also, note that when using ssh, connecting to cs.byu.edu will drop you onto a lab machine. It is also a one-to-many NAT.

Please note that direct access to a specific lab machine is no longer possible, and if you are not on a CS Department machine, you must access the labs in this manner. Once connected to a department machine, you can connect directly to one of the lab machines, in any lab.

When deciding which machines to use, remember the following guidelines:

# The instruments lab has older machines than the rest. # When you get to a machine, type "w" at the command prompt, and you will see a list of all users currently connected to the computer you're on. If there are already several users on, logoff and reconnnect. Hopefully this time you'll get one that's less busy.

In the last section of this document is a list of all of the lab computers should you wish to use a specific machine, once inside the CS Department network.

General Things on Remote Access

System Changes

Individual machines are not directly accessible from outside the department network. You must connect via a lab name, as described in the previous section.

Secure Remote Access to Your Account from Windows

SSH - Secure Shell

Using SSH to Connect to a Linux Computer from the Windows Labs

SSH is installed on all the machines in the CS Department Windows Labs. It's pretty easy to use SSH. The program is located in '''Start Menu -> Programs -> SSH Secure Shell -> Secure Shell Client'''. When the window pops up, press enter and then enter the hostname (the name of the computer you want to connect to) and your username. Later, enter your password.

A "key" will be created the first time you connect with a host. A key will be created for every machine you log into, and if you log in as a different user a different key will also be created. Click yes to accept the new key, and the next time you ssh into that same computer it will use the same key.

Using SSH For File Transfers

To transferring files through SSH just open a connection to a machine as described above. When the connection has been made and you have logged in, go to the "window" menu and then go down to "New File Transfer". A new window will be created where you will see all the files in your directory of the remote machine. You can drag-and-drop files between the local computer and the remote machine.

Getting SSH at Home

PuTTY is an SSH client. It provides the user with a command prompt to execute commands on a remote unix or linux machine. PuTTY does not have file transfer capabilities. It runs as a small standalone executable making it convenient to add to or remove from any system or run from a floppy disk. Each time you use PuTTY make sure that you are using it in SSH mode (encrypted), not in telnet mode. The executable can be downloaded free here: [http://www.chiark.greenend.org.uk/~sgtatham/putty/download.html http://www.chiark.greenend.org.uk/~sgtatham/putty/]

WinSCP

WinSCP is a simple to use scp/sftp client with a windows interface. It allows a user to transfer files to and from a Unix or Linux machine Though it doesn't give a user a command prompt to execute commands on the remote machine, it does allow the user to perform basic file maintenance: copy, delete, rename, make directories, etc. It runs as a small stand alone executable making it convenient to carry on a floppy disk for file transfers from any machine. The executable can be downloaded free here: [http://winscp.vse.cz/eng/download.php winscp.vse.cz]

Secure Remote Access to Your Account from Linux

SSH - Secure Shell

SSH comes packaged with most distributions of linux, and the client is usually a part of the default install. That means that your home machine is probably already configured with an SSH client.

Some examples of how to use the SSH client:

SSH runs from the terminal command line. By default ssh will attempt to log you in under the same username as you are using on your local machine, and it will attempt to resolve the address of the remote machine using the same domain as your local machine. This means that here in the CS labs a command as simple as:

ssh verdi

will log you into the machine verdi with your current username and prompt you for your password.

From a home machine you will probably need to explicitly declare your username and the domain name for the computer you are using. You do this by prepending your remote machine username followed by an @, and/or adding the domain name suffix to the machine name. For example:

yourusername@monsters.cs.byu.edu

will log you into the machine crust with the specified username and prompt you for your password on crust.

If SSH prompts you about creating an RSA key, and you trust the computer you are SSHing into, then simply type "yes."

If you want to learn more about ssh on the Linux boxes just check the manpage ('''man ssh''').

SFTP - Secure FTP

SFTP is used for secure file transfers. It is a version of FTP that uses encryption. It has pretty much same commands as ftp. If you want to read a little more about this, Linux Gazette published an [http://www.linuxgazette.com/issue64/dellomodarme.html article] on SFTP. It explains the pros and cons of SFTP and general usage.

If you want to connect via SFTP just use the following syntax:

sftp myusername@hostname

If you want information on specific commands, check out the man page: "man sftp"

SCP - Secure Copy

SCP is used for secure file transfers. It allows users to securely copy files over a network. It has almost the same syntax as the unix command "cp" (copy). Linux Gazette published an [http://www.linuxgazette.com/issue64/dellomodarme.html article] about the usage of SCP. Check it out. SCP requires you to know the directory structure of the remote machine.

The general syntax is like this: scp -tags sourcefile destinationfile. The sourcefile or destinationfile can be remote files, in which case you append username@hostname: to the filename. Here are a few examples.

  • To copy one file from your local machine to a remote machine:

    "scp localfilename myusername@hostname:remotedir"

System Message: WARNING/2 (<string>, line 129)

Bullet list ends without a blank line; unexpected unindent.

ex:

"scp myfile.txt bob@verdi:tmp"

i.e. Copy the local file myfile.txt to the directory called "tmp" in the home directory of "bob" on verdi. * To copy a file from a remote machine to your local computer in the current directory:

"scp myusername@hostname:remotefilename ."

  • To copy all the files from a directory on a remote machine to your local computer in a directory called "tmp":

    "scp myusername@hostname:remotedirectory/'*'tmp"

Some useful tags are -r (recursive), which recursively copies directories, and -v (verbose), which outputs the progress of the command. You can combine tags behind one dash: -rv.

  • To recursively copy a directory on your local computer to a directory called test1 on a remote computer and output the progress.

    "scp -rv localdirectory myusername@hostname:test1"

There are tons of possible combinations and these are just a few, so if you want information, check out the man page: "'''man scp'''"

List of All Accessible Computers

Please be aware that direct access to a specific machine is only possible from '''within''' the department network. (ie you must already be connected to or working on one of the open lab machines)

Models

The following models are used in the Linux labs:

Dell GX270:CPU: 3.2 GHz Pentium 4, RAM: 1024 MB
HP DC7700:CPU: Intel Core 2 Duo e6400 @ 2.13GHz, RAM: 1024 MB
Apple Mac Mini:CPU: Intel Core Duo @ 1.83 GHz, RAM: 2048 MB

Fruits Lab (1102 TMCB)

This lab is currently not accessible

Lab name (for remote access):
 fruits
Model:Apple Mac Mini
  • apple.cs.byu.edu
  • orange.cs.byu.edu
  • banana.cs.byu.edu
  • pear.cs.byu.edu
  • peach.cs.byu.edu
  • plum.cs.byu.edu
  • kiwi.cs.byu.edu
  • mango.cs.byu.edu
  • cherry.cs.byu.edu
  • grape.cs.byu.edu
  • strawberry.cs.byu.edu
  • blueberry.cs.byu.edu
  • raspberry.cs.byu.edu
  • watermellon.cs.byu.edu
  • apricot.cs.byu.edu
  • nectarine.cs.byu.edu
  • tangerine.cs.byu.edu

Simpsons Lab (1106 TMCB)

Lab name (for remote access):
 simpsons
Model:HP DC7700
  • apu.cs.byu.edu
  • bart.cs.byu.edu
  • burns.cs.byu.edu
  • cletus.cs.byu.edu
  • flanders.cs.byu.edu
  • grampa.cs.byu.edu
  • homer.cs.byu.edu
  • krusty.cs.byu.edu
  • lisa.cs.byu.edu
  • maggie.cs.byu.edu
  • marge.cs.byu.edu
  • milhouse.cs.byu.edu
  • moleman.cs.byu.edu
  • nelson.cs.byu.edu
  • skinner.cs.byu.edu
  • wiggum.cs.byu.edu
  • willie.cs.byu.edu

Weapons Lab (1110 TMCB)

Lab name (for remote access):
 weapons
Model:HP DC7700
  • claymore.cs.byu.edu
  • dagger.cs.byu.edu
  • katana.cs.byu.edu
  • battleaxe.cs.byu.edu
  • halberd.cs.byu.edu
  • knife.cs.byu.edu
  • dirk.cs.byu.edu
  • foil.cs.byu.edu
  • saber.cs.byu.edu
  • crossbow.cs.byu.edu
  • longbow.cs.byu.edu
  • spear.cs.byu.edu
  • pike.cs.byu.edu
  • nunchucks.cs.byu.edu
  • mace.cs.byu.edu
  • club.cs.byu.edu
  • scimitar.cs.byu.edu

Instruments Lab (1027 TMCB)

Lab name (for remote access):
 instruments
Model:Dell GX270
  • organ.cs.byu.edu
  • piano.cs.byu.edu
  • viola.cs.byu.edu
  • horn.cs.byu.edu
  • kazoo.cs.byu.edu
  • guitar.cs.byu.edu
  • banjo.cs.byu.edu
  • tuba.cs.byu.edu
  • flute.cs.byu.edu
  • drums.cs.byu.edu
  • oboe.cs.byu.edu
  • harp.cs.byu.edu
  • voice.cs.byu.edu
  • harmonica.cs.byu.edu
  • trumpet.cs.byu.edu
  • bassoon.cs.byu.edu
  • bagpipes.cs.byu.edu

Sports Lab (1029 TMCB)

Lab name (for remote access):
 sports
Model:HP DC7700
  • archery.cs.byu.edu
  • badminton.cs.byu.edu
  • baseball.cs.byu.edu
  • basketball.cs.byu.edu
  • bowling.cs.byu.edu
  • boxing.cs.byu.edu
  • cricket.cs.byu.edu
  • croquet.cs.byu.edu
  • curling.cs.byu.edu
  • cycling.cs.byu.edu
  • discus.cs.byu.edu
  • diving.cs.byu.edu
  • fencing.cs.byu.edu
  • fishing.cs.byu.edu
  • football.cs.byu.edu
  • gymnastics.cs.byu.edu
  • hockey.cs.byu.edu
  • karate.cs.byu.edu
  • lacrosse.cs.byu.edu
  • paintball.cs.byu.edu
  • pingpong.cs.byu.edu
  • polo.cs.byu.edu
  • racquetball.cs.byu.edu
  • rowing.cs.byu.edu
  • rugby.cs.byu.edu
  • running.cs.byu.edu
  • sailing.cs.byu.edu
  • skating.cs.byu.edu
  • skiing.cs.byu.edu
  • soccer.cs.byu.edu

Monsters Lab (1059 TMCB)

This lab is currently unavailable due to construction

Lab name (for remote access):
 monsters
Model:Dell GX270
  • banshee.cs.byu.edu
  • barney.cs.byu.edu
  • basilisk.cs.byu.edu
  • centaur.cs.byu.edu
  • cerberus.cs.byu.edu
  • chimaera.cs.byu.edu
  • cyclops.cs.byu.edu
  • draco.cs.byu.edu
  • godzilla.cs.byu.edu
  • kingkong.cs.byu.edu
  • kraken.cs.byu.edu
  • lochness.cs.byu.edu
  • medusa.cs.byu.edu
  • minotaur.cs.byu.edu
  • mummy.cs.byu.edu
  • rabbit.cs.byu.edu
  • siren.cs.byu.edu
  • vampire.cs.byu.edu
  • werewolf.cs.byu.edu
  • yeti.cs.byu.edu
  • zombie.cs.byu.edu

Pizza Lab (1057 TMCB)

This lab is not available due to construction

Model:Dell GX270
  • delivery.cs.byu.edu
  • sauce.cs.byu.edu
  • crust.cs.byu.edu
  • box.cs.byu.edu
  • shrimp.cs.byu.edu
  • palmhearts.cs.byu.edu
  • pesto.cs.byu.edu
  • deepdish.cs.byu.edu
  • oven.cs.byu.edu
  • ham.cs.byu.edu
  • sausage.cs.byu.edu
  • cheddar.cs.byu.edu
  • tomatoes.cs.byu.edu
  • anchovies.cs.byu.edu
  • bacon.cs.byu.edu
  • cheese.cs.byu.edu
  • pork.cs.byu.edu
  • pepperoni.cs.byu.edu
  • mushrooms.cs.byu.edu
  • onions.cs.byu.edu