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How To Find An Idle Sun Client?

The actual workstations are often called Sun clients, because they are fed their files from a Sun server, thus the server -> client relationship.

If you have your files on a Sun server and need to edit a file, you don't have to go find a Sun client. Instead, you could use the rlogin command to login to a client that may be down the hall. What you want to do is find a client not in use, because most ECN clients are run under the rules that people who are sitting in front of the client have exclusive use of that machine. Yet, if there is no one using a client, it is silly not to use it! There are a couple of ways to check out which Suns are OK to rlogin into. One way is to type the command "ruptime".

% ruptime
aquarium  up  8+03:22,  0 users,  load  0.71,  0.44,  0.63
atoms     up  4+20:50,  0 users,  load  0.27,  0.40,  0.42
back      up  3+15:00,  0 users,  load  0.24,  0.03,  0.01
bank      up  7+23:50,  9 users,  load  1.01,  0.73,  0.65
cb        up 21+15:32, 27 users,  load  7.33,  5.98,  5.38
 ...etc ...
stable    up  4+17:46, 32 users,  load  1.93,  1.90,  1.76
zoo       up  5+02:36,  1 user,   load  1.95,  2.02,  1.90

But, depending upon WHERE you are when you type "ruptime" you will get the local machine information, which might not include the Sun clients. You could type: "rsh clientname ruptime" as in :

% rsh mackinac ruptime
aqueduct   up 40+19:51,  0 users,  load  0.04,  0.00,  0.00
bart       up 13+22:30,  1 user,   load  0.00,  0.00,  0.00
bidone     up 61+19:37,  0 users,  load  0.05,  0.01,  0.00
bonneville up 34+14:00,  0 users,  load  0.17,  0.01,  0.00
cb         up 21+15:38, 26 users,  load  5.41,  7.76,  6.31
  ... etc ...
vortex     up 11+22:22,  1 user,   load  0.10,  0.13,  0.00
wynoochee  up 13+23:55,  0 users,  load  0.00,  0.00,  0.00

The above shows you that aqueduct, bidone, bonneville, and wynoochee are all prime candidates for use via rlogin! bart and vortex ARE NOT.

You can also check on a specific client with the finger command. (Type "finger" on Suns; however, on older machines, "f" and "finger" are equivalent.)

% finger @mackinac
[mackinac.ecn.purdue.edu]
Login&Name&TTY&Idle&When&Office
stars&Stars/Donald White&co&1:46&Tue 09:49&ce4120
etc.

This means that the person is sitting down in front of the client, and YOU should NOT rlogin to that machine. ("tty co" is the console.) However, if you check another client :

% f @wynoochee
[wynoochee.ecn.purdue.edu]
No one logged on

You find out the same information that "ruptime" showed that wynoochee is not being currently used.

Of course, you need to have an account on a machine before you can login to it!! To see where you have an account, you can type "lname -v login" as in:

% lname -v stars
Login Name      Name          Department   Maildrop    Hosts

stars    Stars/Donald White   Civil Eng.   stars@cb   viaduct,
eurotunnel,sanandreas,hydrolab,aqueduct,bidone,optimizer,
eadsbridge,vaiont,us30,taumsauk,mackinac,jamestown,eriecanal,
chunnel,chesapeake,bonneville,bart,wynoochee,vortex,
surveyor,searstower,planetearth,jitney,hoover,grandcoulee,
goldengate,eddystone,cn,cb

Note: In this example, goldengate and eadsbridge are SERVERS, with a shell of /bin/false. If your shell is /bin/false, you will not be allowed to login to that machine. sp % f stars@goldengate [goldengate.ecn.purdue.edu] Login name: stars&In real life: Stars /Donald White Office: ce4120, 49-46455 Directory: /home/goldengate/stars&Shell: /bin/false Affiliations: ce&Uid: 11204 Expires: September 1999&Login group: other (1) Department: Civil Engineering Classification: Lab Account Never logged in.

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