Level 3 lab map

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This map is primarily aimed at first year computer science students, but may also be useful to others using the level 3 lab.

Sorry, rlogin has been disabled on these computers; the above map will no longer work for you. You will need to ssh to the machines instead. (ssh phair001 etc). Please disregard any references to rlogin below.

If you're in UCC, you can use this map to exchange messages with someone in this lab - find the computer they're at, click its number to connect to it via rlogin (remote login), and login with your usual password (you don't need to type your username, it's already been sent). Then enter " talk xxx1 " (without the quotes), where xxx1 is the username of the person you want to talk to, and they will be notified by a beep that someone wishes to talk to them. They can then see who's logged in to their machine by entering w, who or finger at a prompt, and if they feel like talking to you they can do so by typing " talk yyy1 " at a prompt (without the quotes), where yyy1 is your username. You should then be connected and be able to exchange messages with them. When typing, you can erase the line you're on with Ctrl-U, and the last word with Ctrl-W. When you are finished, close the talk session with Ctrl-C, and close the rlogin connection with Ctrl-D.

So, if you're working away on something and your computer gives a high-pitched beep for no apparent reason, it's probably because someone wants to talk to you. To see who it is, open a shell (command prompt) and enter the " w " command (without the quotes); this will give you a list of who's logged in to your machine and what they're doing. So for the example above you would see a line like " yyy1 pts/1 phair000.ucc.ie 12:00pm 0.00s 0.00s 0.00s talk xxx1 " - if you ignore all the stuff in the middle, this tells you that yyy1 is logged in and is trying to talk to xxx1 (that's you). To talk to them, type " talk yyy1 " (again, without the quotes).

If you can't see the person you want to talk to, do not despair, for all is not lost. They may still be logged in to ocean (aka student.cs.ucc.ie) or wisdom. When connected, use the same commands as above.

Note to pedants: yes, I know talk will work remotely without rlogin. However, whatever way the machines are set up in this lab, most of the time the only notification of an incoming talk request is a beep and if it's a remote talk request there's no way of telling where it's coming from. Hence, the best way to let someone know you want to talk to them is to telnet to their machine so they can see you logged on, and talk to you like a local user.

Also note that the map above will only work when the person you want to talk to is using Linux. If they're using Windows, tough - though if you're using Linux they can still connect to your machine using telnet (Start, Run, type " telnet phair000 ", without the quotes, and changing 000 to the appropriate number, and hit enter) and you can talk that way. Note that Windows users may not be able to use the rlogin links above because Windows blows (and sucks! at the same time!)

Also note that the above links will not work from outside UCC as the machines in this lab are all behind a firewall. For this reason I haven't bothered putting in fully qualified domain names. Additional note: ocean is accessible from outside, but I don't recommend using telnet or rlogin from outside UCC as these protocols are unencrypted and hence allow anyone along the route of your connection to find out your username and password, enabling them to wreak untold havoc with your account (including (but not limited to) reading, deleting and modifying your files, reading your e-mail and sending email to others from your account). For the same reason, I don't recommend using webmail from outside UCC. If you must connect from outside, I strongly suggest using ssh (most linux distributions include an ssh client by default; PuTTY is a good ssh client for windows). Note that if using PuTTY you'll need to tick the "Imitate SSH 2 MAC bug" setting or it'll bomb out complaining about an incorrect MAC address. [note: putty now autodetects this so you don't need to do this unless it bombs out]

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