SSH (Virtual) Computing Element: For a given IP/host it will send jobs directly through ssh

class DIRAC.Resources.Computing.SSHComputingElement.SSH(host=None, parameters=None)

Bases: object

SSH class encapsulates passing commands and files through an SSH tunnel to a remote host. It can use either ssh or gsissh access. The final host where the commands will be executed and where the files will copied/retrieved can be reached through an intermediate host if SSHTunnel parameters is defined.

SSH constructor parameters are defined in a SSH accessible Computing Element in the Configuration System:

  • SSHHost: SSH host name
  • SSHUser: SSH user login
  • SSHPassword: SSH password
  • SSHPort: port number if not standard, e.g. for the gsissh access
  • SSHKey: location of the ssh private key for no-password connection
  • SSHOptions: any other SSH options to be used
  • SSHTunnel: string defining the use of intermediate SSH host. Example:
    ‘ssh -i /private/key/location -l final_user final_host’
  • SSHType: ssh ( default ) or gsissh

The class public interface includes two methods:

sshCall( timeout, command_sequence ) scpCall( timeout, local_file, remote_file, upload = False/True )

__init__(host=None, parameters=None)

x.__init__(…) initializes x; see help(type(x)) for signature

scpCall(timeout, localFile, remoteFile, postUploadCommand='', upload=True)

Perform file copy through an SSH magic.

  • timeout (int) – timeout of the command
  • localFile (str) – local file path, serves as source for uploading and destination for downloading. Can take ‘Memory’ as value, in this case the downloaded contents is returned as result[‘Value’]
  • remoteFile (str) – remote file full path
  • postUploadCommand (str) – command executed on the remote side after file upload
  • upload (bool) – upload if True, download otherwise
sshCall(timeout, cmdSeq)

Execute remote command via a ssh remote call

  • timeout (int) – timeout of the command
  • cmdSeq (list) – list of command components
class DIRAC.Resources.Computing.SSHComputingElement.SSHComputingElement(ceUniqueID)

Bases: DIRAC.Resources.Computing.ComputingElement.ComputingElement


Standard constructor.


This method returns the number of available slots in the target CE. The CE instance polls for waiting and running jobs and compares to the limits in the CE parameters.

Parameters:jobIDList (list) – list of already existing job IDs to be checked against

Method to return information on running and pending jobs.


Get CE description as a dictionary.

This is called by the JobAgent for the case of “inner” CEs.

getJobOutput(jobID, localDir=None)

Get the specified job standard output and error files. If the localDir is provided, the output is returned as file in this directory. Otherwise, the output is returned as strings.


Get the status information for the given list of jobs


Initialize the CE parameters after they are collected from various sources


Check if the stored proxy is valid


Check the sanity of the Computing Element definition


Kill a bunch of jobs


Instantiate object representing the backend batch system

sendOutput(stdid, line)

Callback function such that the results from the CE may be returned.


Update the CPUTime parameter of the CE classAd, necessary for running in filling mode


Add parameters from the given dictionary overriding the previous values

Parameters:ceOptions (dict) – CE parameters dictionary to update already defined ones
setProxy(proxy, valid=0)

Set and prepare proxy to use

  • proxy (str) – proxy to use
  • valid (int) – proxy validity period


submitJob(executableFile, proxy, numberOfJobs=1)

Method to submit job, should be overridden in sub-class.


CE helper function to write a CE proxy string to a file.