The Stanford NLP (Natural Language Processing) Group

A Brief Guide to Working with Multiple Machines in the NLP Group

Easy ssh

It is useful to be able to ssh to any machine without your password (and a few shortcuts depend on this):

ssh-keygen -d -q and hit enter thrice.
cat ~/.ssh/id_dsa.pub >> ~/.ssh/authorized_keys


 chmod 0600 !$ 
 bash -c 'for i in `cat /u/nlp/machine-info/machines.txt`; do ssh $i echo $i; done'
      and type yes for each machine. y is insufficient.



Checking machines

 http://nlp.stanford.edu/local/machines.shtml.
    This displays the status of all NLP machines and is updated every 5 minutes.
    (You'll need to authenticate to access it. The username is nlp;
    the password is Chris's middle name backwards.)


 Alternatively, the mstat command will give much the same information
(make sure you are running the version in /u/nlp/bin/mstat.
Run 'mstat -h' for all options).



 It is good to get in the habit of checking either before running
    any large jobs. To see what jobs you are currently running, the mps command is useful
    - it polls all the machines and generate a ps-style listing of all your jobs. (It takes a few seconds to
    run)



Claiming machines

To claim a machine, put a line of the
    format machinename: reason in ~/.javanlp-claims.
    Claims expire after 5 days.


Being a good NLP citizen

To attach an explanatory note about your jobs, which you should do if you have many and/or long jobs,
  put a line of text in ~/.javanlp-note explaining what you are doing and how long it should take.





Screen tips

 man screen for an introduction

 Put the following in ~/.screenrc:

escape ^pp
defscrollback         999            # default: 100
defencoding utf8
defutf8         on
encoding utf8 utf8
hardstatus alwayslastline "%m/%d %c | %w  "
activity              "activity in %n (%t) [%w:%s]"



This makes ctrl-p the screen escape key rather than ctrl-a,
allows utf8 characters to be displayed correctly,
and shows a status line so you don't forget you're
running screen already and try to run a nested one. (Painful!)



 All you really need to know:
   

    screen -S name to start a new screen with a name

    screen -list to see all your screens
    screen -R name to return to the named screen
    ctrl-p d (within screen) to detach the screen (or ctrl-a d if you didn't remap the escape key as above).
    ctrl-p n (within screen) scroll through the current screens (or ctrl-a n if you didn't remap the escape key as above).
   



 Run gos for a menu
    of all running screens on all machines, and the ability to swap
    between them easily.







With many thanks to William Morgan for the original version of this page
and many of the scripts/tips therein. Page last updated 26 Oct 2009 by Rob Munro.




    

    
      
         
        
          
	    Local links:  
	    NLP lunch ·
	    
	    PAIL lunch ·
            NLP Reading Group ·
	    JavaNLP 
	    (javadocs) ·
	    ScalaNLP ·
	    machines ·
	    Wiki
          
	
        
          
	    Site design by Bill MacCartney