.NET Core C#

SSH Parallel Remote Commands on Multiple Servers

See more SSH Examples

Shows how to execute a command in parallel on multiple servers. .NET Core C#

bool 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..
Chilkat.Ssh ssh1 = new Chilkat.Ssh();
Chilkat.Ssh ssh2 = new Chilkat.Ssh();
Chilkat.Ssh ssh3 = new Chilkat.Ssh();

int port = 22;
success = ssh1.Connect("ssh-server1.com",port);
if (success != true) {
    Debug.WriteLine(ssh1.LastErrorText);
    return;
}

// Authenticate using login/password:
success = ssh1.AuthenticatePw("sshLogin1","sshPassword1");
if (success != true) {
    Debug.WriteLine(ssh1.LastErrorText);
    return;
}

// 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.
string cmd = "sleep 5; date";

// Start each command
int ssh1Channel = ssh1.QuickCmdSend(cmd);
if (ssh1Channel < 0) {
    Debug.WriteLine(ssh1.LastErrorText);
    return;
}

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

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

// Now collect the results of each command.
int pollTimeoutMs = 50;
int numFinished = 0;
int channel;
// Note: You would rewrite this code to use arrays.
bool ssh1Finished = false;
bool ssh2Finished = false;
bool ssh3Finished = false;
while (numFinished < 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 != true) {
        channel = ssh1.QuickCmdCheck(pollTimeoutMs);
        if (channel == -2) {
            Debug.WriteLine(ssh1.LastErrorText);
            return;
        }

        if (channel == ssh1Channel) {
            Debug.WriteLine("---- ssh1 channel " + Convert.ToString(channel) + " finished ----");
            Debug.WriteLine(ssh1.GetReceivedText(channel,"ansi"));
            numFinished = numFinished + 1;
            ssh1Finished = true;
        }

    }

    if (ssh2Finished != true) {
        channel = ssh2.QuickCmdCheck(pollTimeoutMs);
        if (channel == -2) {
            Debug.WriteLine(ssh2.LastErrorText);
            return;
        }

        if (channel == ssh2Channel) {
            Debug.WriteLine("---- ssh2 channel " + Convert.ToString(channel) + " finished ----");
            Debug.WriteLine(ssh2.GetReceivedText(channel,"ansi"));
            numFinished = numFinished + 1;
            ssh2Finished = true;
        }

    }

    if (ssh3Finished != true) {
        channel = ssh3.QuickCmdCheck(pollTimeoutMs);
        if (channel == -2) {
            Debug.WriteLine(ssh3.LastErrorText);
            return;
        }

        if (channel == ssh3Channel) {
            Debug.WriteLine("---- ssh3 channel " + Convert.ToString(channel) + " finished ----");
            Debug.WriteLine(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