condor_findhost(1)					      General Commands Manual						condor_findhost(1)

Name
       condor_findhost find - machine(s) in the pool that can be used with minimal impact on currently running Condor jobs and best meet any spec-
       ified constraints

Synopsis
       condor_findhost [-help] [-m] [-n num] [-c c_expr] [-r r_expr] [-p centralmanagerhostname]

Description
       condor_findhostsearches a Condor pool of machines for the best machine or machines that will have the minimum impact on running Condor jobs
       if  the machine or machines are taken out of the pool. The search may be limited to the machine or machines that match a set of constraints
       and rank expression.

       condor_findhostreturns a fully-qualified domain name for each machine. The search is limited (constrained) to a specific  set  of  machines
       using  the  -coption. The search can use the -roption for rank, the criterion used for selecting a machine or machines from the constrained
       list.

Options
       -help

	  Display usage information and exit

       -m

	  Only search for entire machines. Slots within an entire machine are not considered.

       -n num

	  Find and list up to nummachines that fulfill the specification. numis an integer greater than zero.

       -c c_expr

	  Constrain the search to only consider machines that result from the evaluation of c_expr. c_expris a ClassAd expression.

       -r r_expr

	  r_expris the rank expression evaluated to use as a basis for machine selection. r_expris a ClassAd expression.

       -p centralmanagerhostname

	  Specify the pool to be searched by giving the central manager's host name. Without this option, the current pool is searched.

General Remarks
       condor_findhostis used to locate a machine within a pool that can be taken out of the pool with the least disturbance of the pool.

       An administrator should set preemption requirements for the Condor pool. The expression

       (Interactive =?= TRUE )

       will let condor_findhostknow that it can claim a machine even if Condor would not normally preempt a job running on that machine.

Exit Status
       The exit status of condor_findhostis zero on success. If not able to identify as many machines as requested, it returns one more  than  the
       number  of  machines identified. For example, if 8 machines are requested, and condor_findhostonly locates 6, the exit status will be 7. If
       not able to locate any machines, or an error is encountered, condor_findhostwill return the value 1.

Examples
       To find and list four machines, preferring those with the highest mips (on Drystone benchmark) rating:

       condor_findhost	-n 4 -r "mips"

       To find and list 24 machines, considering only those where the  kflops attribute is not defined:

       condor_findhost	-n 24 -c "kflops=?=undefined"

Author
       Condor Team, University of Wisconsin-Madison

Copyright
       Copyright (C) 1990-2012 Condor Team, Computer Sciences Department, University of  Wisconsin-Madison,  Madison,  WI.  All  Rights  Reserved.
       Licensed under the Apache License, Version 2.0.

       See the Condor Version 7.8.2 Manualor http://www.condorproject.org/licensefor additional notices.

       condor-admin@cs.wisc.edu

								  September 2012						condor_findhost(1)