Home

About
Overview
What's New
Publications
SLURM Team

Using
Documentation
FAQ
Getting Help

Installing
Platforms
Download
Guide

## Quick Start Administrator Guide

### Overview

Please see the Quick Start User Guide for a general overview.

### Building and Installing

Basic instructions to build and install SLURM from source are shown below. See the README and INSTALL files in the source distribution for more details.

1. cd to the directory containing the SLURM source and type ./configure with appropriate options.
2. Type make to compile SLURM.
3. Type make install to install the programs, documentation, libaries, header files, etc.

The most commonly used arguments to the configure command include:

--enable-debug
Enable debugging of individual modules.

--prefix=PREFIX
Install architecture-independent files in PREFIX; default value is /usr/local.

--sysconfdir=DIR
Specify location of SLURM configuration file.

Optional SLURM plugins will be built automatically when the configure script detects that the required build requirements are present. Build dependencies for various plugins are denoted below.

- Munge The auth/munge plugin will be built if Chris Dunlap's Munge library is installed.
- Authd The auth/authd plugin will be built and installed if the libauth library and its dependency libe are installed.
- QsNet QsNet support in the form of the switch/elan plugin requires that the qsnetlibs package (from Quadrics) be installed along with its development counterpart (i.e. the qsnetheaders package.) The switch/elan plugin also requires the presence of the libelanosts library and /etc/elanhosts configuration file. (See elanhosts(5) man page in that package for more details)

Please see the Download page for references to required software to build these plugins.

### Daemons

slurmctld is sometimes called the "controller" daemon. It orchestrates SLURM activities, including queuing of job, monitoring node state, and allocating resources (nodes) to jobs. There is an optional backup controller that automatically assumes control in the event the primary controller fails. The primary controller resumes control whenever it is restored to service. The controller saves its state to disk whenever there is a change. This state can be recovered by the controller at startup time. slurmctld would typically execute as a special user specifically for this purpose (not user root). State changes are saved so that jobs and other state can be preserved when slurmctld moves or is restarted.

The slurmd daemon executes on every compute node. It resembles a remote shell daemon to export control to SLURM. Because slurmd initiates and manages user jobs, it must execute as the user root.

slurmctld and/or slurmd should be initiated at node startup time per the SLURM configuration.

### Infrastructure

#### Authentication of SLURM communications

All communications between SLURM components are authenticated. The authentication infrastructure is provided by a dynamically loaded plugin chosen at runtame via the AuthType keyword in the SLURM configuration file. Currently available authentication types include authd, munge, and none. The default authentication infrastructure is "none". This permits any user to execute any job as another user. This may be fine for testing purposes, but certainly not for production use. Configure some AuthType value other than "none" if you want any security. We recommend the use of Munge unless you are experienced with authd.

While SLURM itself does not rely upon synchronized clocks on all nodes of a cluster for proper operation, its underlying authentication mechanism may have this requirement. For instance, if SLURM is making use of the auth/munge plugin for communication, the clocks on all nodes will need to be synchronized.

#### MPI support

Quadrics MPI works directly with SLURM on systems having Quadrics interconnects. For non-Quadrics interconnect systems, LAM/MPI is the preferred MPI infrastructure. LAM/MPI uses the command lamboot to initiate job-specific daemons on each node using SLURM's srun command. This places all MPI processes in a process-tree under the control of the slurmd daemon. LAM/MPI version 7.1 or higher contains support for SLURM.

#### Scheduler support

SLURM's default scheduler is FIFO (First-In First-Out). A backfill scheduler plugin is also available. Backfill scheduling will initiate a lower-priority job if doing so does not delay the expected initiation time of higher priority jobs; essentially using smaller jobs to fill holes in the resource allocation plan. The Maui Scheduler offers sophisticated scheduling algorithms to control SLURM's workload. Motivated users can even develop their own scheduler plugin if so desired.

SLURM uses the syslog function to record events. It uses a range of importance levels for these messages. Be certain that your system's syslog functionality is operational.

#### Corefile format

SLURM is designed to support generating a variety of core file formats for application codes that fail (see the --core option of the srun command). As of now, SLURM only supports a locally developed lightweight corefile library which has not yet been released to the public. It is expected that this library will be available in the near future.

#### Parallel debugger support

SLURM exports information for parallel debuggers using the specification detailed here. This is meant to be exploited by any parallel debugger (notably, TotalView), and support is unconditionally compiled into SLURM code.

### Configuration

The SLURM configuration file includes a wide variety of parameters. This configuration file must be available on each node of the cluster. A full description of the parameters is included in the slurm.conf man page. Rather than duplicate that information, a sample configuration file is shown below. Any text following a "#" is considered a comment. The keywords in the file are not case sensitive, although the argument typically is (e.g., "SlurmUser=slurm" might be specified as "slurmuser=slurm"). The control machine, like all other machine specifications, can include both the host name and the name used for communications. In this case, the host's name is "mcri" and the name "emcri" is used for communications. The "e" prefix identifies this as an ethernet address at this site. Port numbers to be used for communications are specified as well as various timer values.

A description of the nodes and their grouping into non-overlapping partitions is required. Partition and node specifications use node range expressions to identify nodes in a concise fashion. This configuration file defines a 1154-node cluster for SLURM, but it might be used for a much larger cluster by just changing a few node range expressions. Specify the minimum processor count (Procs), real memory space (RealMemory, megabytes), and temporary disk space (TmpDisk, megabytes) that a node should have to be considered available for use. Any node lacking these minimum configuration values will be considered DOWN and not scheduled.

    #
    # Sample /etc/slurm.conf for mcr.llnl.gov
    #
    ControlMachine=mcri   ControlAddr=emcri
    #
    AuthType=auth/munge
    Epilog=/usr/local/slurm/etc/epilog
    FastSchedule=1
    JobCompLoc=/var/tmp/jette/slurm.job.log
    JobCompType=jobcomp/filetxt
    JobCredentialPrivateKey=/usr/local/etc/slurm.key
    JobCredentialPublicCertificate=/usr/local/etc/slurm.cert
    PluginDir=/usr/local/slurm/lib/slurm
    Prolog=/usr/local/slurm/etc/prolog
    SchedulerType=sched/backfill
    SlurmUser=slurm
    SlurmctldPort=7002
    SlurmctldTimeout=300
    SlurmdPort=7003
    SlurmdSpoolDir=/var/tmp/slurmd.spool
    SlurmdTimeout=300
    StateSaveLocation=/tmp/slurm.state
    SwitchType=switch/elan
    #
    # Node Configurations
    #
    NodeName=DEFAULT Procs=2 RealMemory=2000 TmpDisk=64000 State=UNKNOWN
    NodeName=mcr[0-1151]  NodeAddr=emcr[0-1151]
    #
    # Partition Configurations
    #
    PartitionName=DEFAULT State=UP
    PartitionName=pdebug Nodes=mcr[0-191] MaxTime=30 MaxNodes=32 Default=YES
    PartitionName=pbatch Nodes=mcr[192-1151]

### Security

You will should create unique job credential keys for your site using the program openssl. You must use openssl and not ssh-genkey to construct these keys. An example of how to do this is shown below. Specify file names that match the values of JobCredentialPrivateKey and JobCredentialPublicCertificate in your configuration file. The JobCredentialPrivateKey file must be readable only by SlurmUser. The JobCredentialPublicCertificate file must be readable by all users. Both files must be available on all nodes in the cluster.

openssl genrsa -out /usr/local/etc/slurm.key 1024
openssl rsa -in /usr/local/etc/slurm.key -pubout -out /usr/local/etc/slurm.cert

SLURM does not use reserved ports to authenticate communication between components. You will need to have at least one "auth" plugin. Currently, only three authentication plugins are supported: auth/none, auth/authd, and auth/munge. The auth/none plugin is built and used by default, but either Brent Chun's authd, or Chris Dunlap's munge should be installed in order to get properly authenticated communications. Unless you are experience with authd, we recommend the use of munge. The configure script in the top-level directory of this distribution will determine which authentication plugins may be built. The configuration file specifies which of the available plugins will be utilized.

A PAM module (Pluggable Authentication Module) is available for SLURM that can prevent a user from accessing a node which he has not been allocated, if that mode of operation is desired.

### Starting the Daemons

For testing purposes you may want to start by just running slurmctld and slurmd on one node. By default, they execute in the background. Use the -D option for each daemon to execute them in the foreground and logging will be done to your terminal. The -v option will log events in more detail with more v's increasing the level of detail (e.g. -vvvvvv). You can use one window to execute slurmctld -D -vvvvvv, a second window to execute slurmd -D -vvvvv, and a third window to execute commands such as srun -N1 /bin/hostname to confirm basic functionality.

Another important option for the daemons is -c to clear previous state information. Without the -c option, the daemons will restore any previously saved state information: node state, job state, etc. With the -c option all previously running jobs will be purged and node state will be restored to the values specified in the configuration file. This means that a node configured down manually using the scontrol command will be returned to service unless also noted as being down in the configuration file. In practice, SLURM restarts with preservation consistently.

A thorough battery of tests written in the "expect" language is also available.

### Administration Examples

scontrol can be used to print all system information and modify most of it. Only a few examples are shown below. Please see the scontrol man page for full details. The commands and options are all case insensitive.

Print detailed state of all jobs in the system.

    adev0: scontrol
    scontrol: show job
    JobId=475 UserId=bob(6885) Name=sleep JobState=COMPLETED
       Priority=4294901286 Partition=batch BatchFlag=0
       AllocNode:Sid=adevi:21432 TimeLimit=UNLIMITED
       StartTime=03/19-12:53:41 EndTime=03/19-12:53:59
       NodeList=adev8 NodeListIndecies=-1
       ReqProcs=0 MinNodes=0 Shared=0 Contiguous=0
       MinProcs=0 MinMemory=0 Features=(null) MinTmpDisk=0
       ReqNodeList=(null) ReqNodeListIndecies=-1

    JobId=476 UserId=bob(6885) Name=sleep JobState=RUNNING
       Priority=4294901285 Partition=batch BatchFlag=0
       AllocNode:Sid=adevi:21432 TimeLimit=UNLIMITED
       StartTime=03/19-12:54:01 EndTime=NONE
       NodeList=adev8 NodeListIndecies=8,8,-1
       ReqProcs=0 MinNodes=0 Shared=0 Contiguous=0
       MinProcs=0 MinMemory=0 Features=(null) MinTmpDisk=0
       ReqNodeList=(null) ReqNodeListIndecies=-1

Print the detailed state of job 477 and change its priority to zero. A priority of zero prevents a job from being initiated (it is held in "pending" state).

    adev0: scontrol
    scontrol: show job 477
    JobId=477 UserId=bob(6885) Name=sleep JobState=PENDING
       Priority=4294901286 Partition=batch BatchFlag=0
       more data removed....
    scontrol: update JobId=477 Priority=0

Print the state of node adev13 and drain it. To drain a node specify a new state of DRAIN, DRAINED, or DRAINING. SLURM will automatically set it to the appropriate value of either DRAINING or DRAINED depending on whether the node is allocated or not. Return it to service later.

    adev0: scontrol
    scontrol: show node adev13
    NodeName=adev13 State=ALLOCATED CPUs=2 RealMemory=3448 TmpDisk=32000
       Weight=16 Partition=debug Features=(null)
    scontrol: update NodeName=adev13 State=DRAIN
    scontrol: show node adev13
    NodeName=adev13 State=DRAINING CPUs=2 RealMemory=3448 TmpDisk=32000
       Weight=16 Partition=debug Features=(null)
    scontrol: quit
    Later
    adev0: scontrol
    scontrol: show node adev13
    NodeName=adev13 State=DRAINED CPUs=2 RealMemory=3448 TmpDisk=32000
       Weight=16 Partition=debug Features=(null)
    scontrol: update NodeName=adev13 State=IDLE

Reconfigure all SLURM daemons on all nodes. This should be done after changing the SLURM configuration file.

    adev0: scontrol reconfig

Print the current SLURM configuration. This also reports if the primary and secondary controllers (slurmctld daemons) are responding. To just see the state of the controllers, use the command ping.

    adev0: scontrol show config
    Configuration data as of 03/19-13:04:12
    AuthType          = auth/munge
    BackupAddr        = eadevj
    BackupController  = adevj
    ControlAddr       = eadevi
    ControlMachine    = adevi
    Epilog            = (null)
    FastSchedule      = 1
    FirstJobId        = 1
    NodeHashBase      = 10
    HeartbeatInterval = 60
    InactiveLimit     = 0
    JobCompLoc        = /var/tmp/jette/slurm.job.log
    JobCompType       = jobcomp/filetxt
    JobCredPrivateKey = /etc/slurm/slurm.key
    JobCredPublicKey  = /etc/slurm/slurm.cert
    KillWait          = 30
    MaxJobCnt         = 2000
    MinJobAge         = 300
    PluginDir         = /usr/lib/slurm
    Prolog            = (null)
    ReturnToService   = 1
    SchedulerAuth     = (null)
    SchedulerPort     = 65534
    SchedulerType     = sched/backfill
    SlurmUser         = slurm(97)
    SlurmctldDebug    = 4
    SlurmctldLogFile  = /tmp/slurmctld.log
    SlurmctldPidFile  = /tmp/slurmctld.pid
    SlurmctldPort     = 7002
    SlurmctldTimeout  = 300
    SlurmdDebug       = 65534
    SlurmdLogFile     = /tmp/slurmd.log
    SlurmdPidFile     = /tmp/slurmd.pid
    SlurmdPort        = 7003
    SlurmdSpoolDir    = /tmp/slurmd
    SlurmdTimeout     = 300
    SLURM_CONFIG_FILE = /etc/slurm/slurm.conf
    StateSaveLocation = /usr/local/tmp/slurm/adev
    SwitchType        = switch/elan
    TmpFS             = /tmp
    WaitTime          = 0

    Slurmctld(primary/backup) at adevi/adevj are UP/UP

Shutdown all SLURM daemons on all nodes.

    adev0: scontrol shutdown

For information about this page, contact slurm-dev@lists.llnl.gov.