PowerShell

SSH Parallel Remote Commands on Multiple Servers

See more SSH Examples

Shows how to execute a command in parallel on multiple servers. PowerShell

Add-Type -Path "C:\chilkat\ChilkatDotNet47-x64\ChilkatDotNet47.dll"

$success = $false

# This example requires the Chilkat API to have been previously unlocked.
# See Global Unlock Sample for sample code.

# Executing a command on multiple servers simultaneously is straightforward.
# It's just a matter of using one SSH object per server..
$ssh1 = New-Object Chilkat.Ssh
$ssh2 = New-Object Chilkat.Ssh
$ssh3 = New-Object Chilkat.Ssh

$port = 22
$success = $ssh1.Connect("ssh-server1.com",$port)
if ($success -ne $true) {
    $($ssh1.LastErrorText)
    exit
}

# Authenticate using login/password:
$success = $ssh1.AuthenticatePw("sshLogin1","sshPassword1")
if ($success -ne $true) {
    $($ssh1.LastErrorText)
    exit
}

# Connect and authenticate with 2 more servers.
# For brevity, the success/failure won't be checked...
$success = $ssh2.Connect("ssh-server2.com",$port)
$success = $ssh2.AuthenticatePw("sshLogin2","sshPassword2")
$success = $ssh3.Connect("ssh-server3.com",$port)
$success = $ssh3.AuthenticatePw("sshLogin3","sshPassword3")

# Note: If we wanted, we could've used ConnectAsync and AuthenticatePwAsync
# to do the connecting and authenticating in parallel...

# The command to be run on each SSH server will sleep for 5 seconds,
# and then show the current system date/time.
$cmd = "sleep 5; date"

# Start each command
$ssh1Channel = $ssh1.QuickCmdSend($cmd)
if ($ssh1Channel -lt 0) {
    $($ssh1.LastErrorText)
    exit
}

# For brevity, we're not checking the return values here:
$ssh2Channel = $ssh2.QuickCmdSend($cmd)
$ssh3Channel = $ssh3.QuickCmdSend($cmd)

# OK, at this point the command is running simultaneously on each server.

# Now collect the results of each command.
$pollTimeoutMs = 50
$numFinished = 0

# Note: You would rewrite this code to use arrays.
$ssh1Finished = $false
$ssh2Finished = $false
$ssh3Finished = $false
while ($numFinished -lt 3) {
    # Check to see if anything has finished.
    # QuickCmdCheck returns -1 if there are no errors and nothing else finished
    # QuickCmdCheck returns -2 if there was an error (such as a lost connection)
    # QuickCmdCheck returns a channel number if a channel finished.
    if ($ssh1Finished -ne $true) {
        $channel = $ssh1.QuickCmdCheck($pollTimeoutMs)
        if ($channel -eq -2) {
            $($ssh1.LastErrorText)
            exit
        }

        if ($channel -eq $ssh1Channel) {
            $("---- ssh1 channel " + $channel + " finished ----")
            $($ssh1.GetReceivedText($channel,"ansi"))
            $numFinished = $numFinished + 1
            $ssh1Finished = $true
        }

    }

    if ($ssh2Finished -ne $true) {
        $channel = $ssh2.QuickCmdCheck($pollTimeoutMs)
        if ($channel -eq -2) {
            $($ssh2.LastErrorText)
            exit
        }

        if ($channel -eq $ssh2Channel) {
            $("---- ssh2 channel " + $channel + " finished ----")
            $($ssh2.GetReceivedText($channel,"ansi"))
            $numFinished = $numFinished + 1
            $ssh2Finished = $true
        }

    }

    if ($ssh3Finished -ne $true) {
        $channel = $ssh3.QuickCmdCheck($pollTimeoutMs)
        if ($channel -eq -2) {
            $($ssh3.LastErrorText)
            exit
        }

        if ($channel -eq $ssh3Channel) {
            $("---- ssh3 channel " + $channel + " finished ----")
            $($ssh3.GetReceivedText($channel,"ansi"))
            $numFinished = $numFinished + 1
            $ssh3Finished = $true
        }

    }

}

# --------------
# Sample output:

# 	---- ssh2 channel 101 finished ----
# 	Fri Dec 23 00:25:48 UTC 2016
# 
# 	---- ssh3 channel 102 finished ----
# 	Thu Dec 22 18:25:12 CST 2016
# 
# 	---- ssh1 channel 100 finished ----
# 	Thu Dec 22 18:25:48 CST 2016