# condor_drain¶

Control draining of an execute machine

## Synopsis¶

condor_drain [-help ]

condor_drain [-debug ] [-pool pool-name] [-graceful | -quick | -fast ] [-resume-on-completion ] [-check expr] [-start expr] machine-name

condor_drain [-debug ] [-pool pool-name] -cancel [-request-id id] machine-name

## Description¶

condor_drain is an administrative command used to control the draining of all slots on an execute machine. When a machine is draining, it will not accept any new jobs unless the -start expression specifies otherwise. Which machine to drain is specified by the argument machine-name, and will be the same as the machine ClassAd attribute Machine.

How currently running jobs are treated depends on the draining schedule that is chosen with a command-line option:

-graceful
Initiate a graceful eviction of the job. This means all promises that have been made to the job are honored, including MaxJobRetirementTime. The eviction of jobs is coordinated to reduce idle time. This means that if one slot has a job with a long retirement time and the other slots have jobs with shorter retirement times, the effective retirement time for all of the jobs is the longer one. If no draining schedule is specified, -graceful is chosen by default.
-quick
MaxJobRetirementTime is not honored. Eviction of jobs is immediately initiated. Jobs are given time to shut down and produce checkpoints, according to the usual policy, that is, given by MachineMaxVacateTime.
-fast
Jobs are immediately hard-killed, with no chance to gracefully shut down or produce a checkpoint.

If you specify -graceful, you may also specify -start. On a gracefully-draining machine, some jobs may finish retiring before others. By default, the resources used by the newly-retired jobs do not become available for use by other jobs until the machine exits the draining state (see below). The -start expression you supply replaces the draining machine’s normal START expression for the duration of the draining state, potentially making those resources available. See the condor_startd Policy Configuration section for more information.

Once draining is complete, the machine will enter the Drained/Idle state. To resume normal operation (negotiation) at that time or any previous time during draining, the -cancel option may be used. The -resume-on-completion option results in automatic resumption of normal operation once draining has completed, and may be used when initiating draining. This is useful for forcing a machine with a partitionable slots to join all of the resources back together into one machine, facilitating de-fragmentation and whole machine negotiation.

## Options¶

-help
Display brief usage information and exit.
-debug
Causes debugging information to be sent to stderr, based on the value of the configuration variable TOOL_DEBUG.
-pool pool-name
Specify an alternate HTCondor pool, if the default one is not desired.
-graceful
(the default) Honor the maximum vacate and retirement time policy.
-quick
Honor the maximum vacate time, but not the retirement time policy.
-fast
Honor neither the maximum vacate time policy nor the retirement time policy.
-resume-on-completion
When done draining, resume normal operation, such that potentially the whole machine could be claimed.
-check expr
Abort draining, if expr is not true for all slots to be drained.
-start expr
The START expression to use while the machine is draining. You can’t reference the machine’s existing START expression.
-cancel
Cancel a prior draining request, to permit the condor_negotiator to use the machine again.
-request-id id
Specify a specific draining request to cancel, where id is given by the DrainingRequestId machine ClassAd attribute.

## Exit Status¶

condor_drain will exit with a non-zero status value if it fails and zero status if it succeeds.

## Author¶

Center for High Throughput Computing, University of Wisconsin-Madison