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C#: Programmatically Detect Windows Server Has Booted

I'm working on an automation process in C# that is going to remotely reboot a Windows (2008/2012/2016) server and I need to wait until that server is back online before proceeding.
I know 'back online' can be ambiguous, so for my requirements, I need the server to be back at the Ctrl-Alt-Del screen.
The reason for this is to have the server in a consistent state before proceeding. In my experience, there are several factors that could prevent the server from reaching this screen, such as installing windows updates that gets stuck in a reboot cycle or getting stuck at 'Waiting for Local Session Manager' etc.
I've spent a few days looking in to this to no avail:
The server obviously starts responding to ping requests before it is available
System Boot Time occurs before the Server reaches the desired state
Any events indicating the system has booted are logged before the desired state
I can't simply poll for an essential service - when Windows is applying computer updates prior to logon these services can be already started. Additionally, sometimes a server will reboot itself whilst installing updates at this stage which could result in false positives.
Polling CPU activity could also produce false positives or introduce delays
Is there anyway to detect a Windows server has finished booting and is available for an interactive logon?

It sounds like you've covered most of the possible ways I know of. Which makes me revert to brute force ideas. I am curious what you're doing where you can't install a windows service on the box (or is that just not very viable because of the number)
First would just be trying to remote login or whatever, and having some way to test if it fails or not, wait 1 minute, try again. But seems like that might cause side-issues for you somehow?
My idea of a brute force method that wouldn't affect state:
Ping every 1-5seconds
Once it starts responding
wait 5 or 10 or even 15 minutes, whilst still pinging it
If pings fail reset that timer (windows updates restart case)
Then be pretty confident you're at the right state.
With potentially thousands of servers, I can't imagine 15 minutes each would be a big deal, especially if it is consistent enough to be able to run in larger batches

So I've been able to accomplish this by using a hacky method put seems to work in my test environment.
Note that the el.Current.Name property will equate to the Ctrl-Alt-Del text, so on 2008R2 this is 'Press CTRL-ALT-DEL to log on' and 'Press CTRL-ALT-DEL to sign in.' on 2012R2
I've built a C# console application that uses UI Automation:
using System;
using System.Windows.Automation;
namespace WorkstationLocked
{
class Program
{
static void Main()
{
AutomationElement el = AutomationUI.FindElementFromAutomationID("LockedMessage");
if (el !=null)
{
Console.WriteLine(el.Current.Name);
}
}
}
class AutomationUI
{
public static AutomationElement FindElementFromAutomationID(string automationID)
{
string className = "AUTHUI.DLL: LogonUI Logon Window";
PropertyCondition condition = new PropertyCondition(AutomationElement.ClassNameProperty, className);
AutomationElement logonui = AutomationElement.RootElement.FindFirst(TreeScope.Children, condition);
if (logonui != null)
{
condition = new PropertyCondition(AutomationElement.AutomationIdProperty, automationID);
return logonui.FindFirst(TreeScope.Descendants, condition);
}
else
{
return null;
}
}
}
}
I can then execute this console application via PsExec, however, because this needs to be launched in the winlogon desktop, which can only be done by running under the local system, PsExec is invoked twice. For example:
psexec.exe \\ServerA -s -d C:\PsTools\PsExec.exe -accepteula -d -x C:\Utils\WorkstationLocked.exe
This is very much a work in progress right now as I can't get the output of the command to pass through to the calling process so I may just look to populate a registry value or write to a file that can be subsequently interrogated.

ASP.NET Process Start

I made new project (ASP.NET MVC Web Application) using Visual Studio Web 2013 Express Edition. Loading index page, redirects and everything works fine, except that in some part of my code I need to create Process and execute it, wait for it to finish, parse output of that external application and show that output to the user. However I get nothing. While debugging the code line by line:
ProcessStartInfo info = new ProcessStartInfo();
info.FileName = Tool;
info.Arguments = filename + " " + avArray;
info.CreateNoWindow = true;
info.UseShellExecute = false;
info.RedirectStandardOutput = true;
Process p = new Process();
p.StartInfo = info;
p.Start();
p.WaitForExit();
Process exits immediately, someone would say it is pretty fast program, but application needs at least 5 seconds (sometimes 20 seconds) to complete.
What I think is happening is that process is not created in the first place, as my IIS settings or whatever other settings are not allowing me to run this EXE. What do I do to change this?

I've been trying to this for the past 2 weeks, I've read probably every post about it, and tried every solution suggested. I am choosing to write on this post since it is the most recent.
First of all, I am using VS2013, testing on IIS Express, and then on IIS 8.5., the webpages version is 3, and the target framework 4.5. And I am assuming that (as with my case) the goal is to launch the process on the server.
What I learned:
Using IIS Express should allow you to run the process without problems. You can try to allow it to launch the window, or start your process through the shell just to be sure that it is actually launching (a shell window should popup and close). If this happens, verify that you are giving the correct path to to your program, etc. So far so good.
Going into the IIS 8.5 is a totally different matter. Theoretically, the bad way of doing it should be preatty straight-forward: you create an app-pool for that server, give it a high privileged account (local system or network system, for instance); go to AdministrativeTools->Services->IIS, LogOn tab, and allow interaction with the desktop. You should be able to do the same as in IISExpress, but in my case is just the same as with a low privilege account.
I actually started by trying just to use impersonation, but also was not able to launch the process with IIS8.5. EDIT: I retried this again today, and the api won't even run if I enable impersonation.
I've spent more time than I would like with this, any input on why I can't get this to work properly with IIS8.5 (#clzola: IIS Express should do the job) is very welcome.

Accessing the Ubuntu terminal from Mono

Background
I'm writing an web application so I can control an Ubuntu Server from a web site.
One idea I had was to run the 'screen' application from mono and redirect my input and output from there.
Running 'screen' from mono:
ProcessStartInfo info = new ProcessStartInfo("screen", "-m");
info.UseShellExecute = false;
info.RedirectStandardOutput = true;
info.RedirectStandardInput = true;
var p = new Process();
p.StartInfo = info;
p.Start();
var output = p.StandardOutput;
var input = p.StandardInput;
but running 'screen' with the RedirectStandardInput gives out the error:
Must be connected to a terminal
I've tried many different arguments and none seems to work with 'Redirecting Standard Input'
Other ideas for controlling a server will be greatly appreciated

I think this is the typical question in which you're asking how to implement your solution to a problem, instead of asking how to solve your problem. I don't think you should do hacky things like making a web app that tunnels the user actions to the server via a terminal.
I think you can bypass all that and, without writing a single line of code, take advantage of what the platform (Gtk+ in this case) already provides you:
You could run gnome-terminal in the server with the Broadway GDK backend. This way the gnome-terminal app will not run in the server, but open a web server on the port you specify. Later, you can use any WebSockets-enabled browser to control it.
This is the easiest and less hacky solution compared to the other ones offered so far. If you still are excited about using Mono for web development you still can, and you could embed this access in an iFrame or something.
(PS: If you don't want to depend on GTK being installed in the server; you could just use WebSockets in your client part of the webpage to be able to send events from the server to the client, and the library SSHNET to send the user's input directly through the wire.)

screen will need a terminal of some sort. It's also gigantically overkill.
You may wish to investigate the pty program from the Advanced Programming in the Unix Environment book (pty/ in the sources) to provide a pseudo-terminal that you can drive programmatically. (You'd probably run the pty program as-provided and write your driver in Mono if you're so inclined.) (The pty program will make far more sense if studied in conjunction with the book.)
The benefit to using the pty program, or functionality similar to it, is that you'd properly handle programs such as passwd that open("/dev/tty") to prompt the user for a password. If you simply redirect standard IO streams via pipe() and dup2() system calls, you won't have a controlling terminal for the programs that need one. (This is still a lot of useful programs but not enough to be a remote administration tool.)
There may be a Mono interface to the pty(7) system; if so, it may be more natural to use it than to use the C API, but the C API is what does the actual work, so it may be easier to just write directly in the native language.

A different approach to solve the same problem is shellinabox. Also interesting is this page from the anyterm website that compares different products that implement this kind of functionality.
Using shellinabox is very simple:
# ./shellinaboxd -s /:LOGIN
(this is the example given on their website) will start a webserver (on in your case the Ubuntu server). When you point your browser to http://yourserver:4200 you'll see a login screen, just like you would see when opening a session with ssh/putty/telnet/... but in your browser.
You could provide the required remote access functionality to the server's shell by just including an iframe that points to that service in your application's webpage.

System calls from .NET to mono [duplicate]

Here is the premise:
I have a desktop that I need to be able to start up and stop applications on, but cannot get remote access to. What I had in mind is setting up a service on the machine that will start/stop a list of applications as told. This windows service will periodically pole a web service for new commands and execute them accordingly.
These are my questions.
1) Is this the easiest solution? What else would you recommend?
2) How hard is it to run an exe from a windows service? How about stopping one?
This isn't for a project or anything, just something I am interested in implementing (mostly for fun). Any answers or even thoughts are appreciated. General discussion is also welcome (feel free to leave comments).

As for creating the Windows service itself in C#, see my post here.
The polling mechanism would work, but in general, I prefer event-driven processes instead of polling processes. You didn't mention what version of .NET you were using, but if it is .NET 3.0/3.5, I would suggest using WCF. When the command is posted to the web service, the web service could send the command to the Windows service to be executed. Pretty straightforward. Juval Lowy, the author of Programming WCF Services, offers a bunch of WCF examples/libraries that are free to use at his website.

So I guess PsExec is out of question?
Other than that, it's not hard to implement running of programs inside a Win service. Simply use the .NET Process class to do it, sample from my code:
ProcessStartInfo processStartInfo = new ProcessStartInfo (programExePath, commandLineArgs);
consoleLogger.WriteLine (log, Level.Debug, "Running program {0} ('{1}')", programExePath, commandLineArgs);
processStartInfo.CreateNoWindow = true;
processStartInfo.ErrorDialog = false;
processStartInfo.RedirectStandardError = true;
processStartInfo.RedirectStandardOutput = true;
processStartInfo.UseShellExecute = false;
using (Process process = new Process ())
{
process.StartInfo = processStartInfo;
process.ErrorDataReceived += new DataReceivedEventHandler (process_ErrorDataReceived);
process.OutputDataReceived += new DataReceivedEventHandler (process_OutputDataReceived);
process.Start ();
process.BeginOutputReadLine ();
process.BeginErrorReadLine ();
if (false == process.WaitForExit ((int)TimeSpan.FromHours(1).TotalMilliseconds))
throw new ArgumentException("The program '{0}' did not finish in time, aborting.", programExePath);
if (process.ExitCode != 0)
throw new ArgumentException ("failed.");
}

I have done a service that starts other exe files. There are some things to consider: As a service you have no visual desktop -> no direct interaction is possible. Also, the program must be designed to run a long while.
Stopping an exe is to kill the process. Consider the usual side-effects.

It wouldn't be too difficult - you can just have it poll some webservice for a list of "banned" applications every so often, and then on another timer, have it check for a banned application that's running and kill it if it is. Here's some code to get a list of processes, and you can use the methods on the process class to launch or kill something:
http://www.vbdotnetheaven.com/UploadFile/prvn_131971/machineprocessvb11182005001454AM/machineprocessvb.aspx
The timers could run independently as well - it can check the webservice once/day for a new add/prohibited list, but then check the processes running on the computer every 2 minutes, for example.

I'll answer question 2 first:
To start or stop programs, you just need to use the System.Diagnostics.Process object, and the example code is right in the MSDN library.
For question 1:
You could have it poll a web service periodically if you want to do that.
As an alternate, you can set up the service for remoting and have it just listen on a tcp port for function calls, then write a Windows app that can use remoting to call the service. I've had to do this for a legitimate business app and it works very well.
However, I would be very irresponsible if I didn't include this warning:
Either way, setting up a computer so that it can execute arbitrary code is a bad idea and should be done very carefully. Just because it can be done doesn't mean it should be done. If you go the web service route, how are you going to ensure that someone doesn't tamper with the web service and get malicious code to execute? How do you know someone won't mess with your app.config and point the app to their own web service? In the remoting scenario, how to you ensure that some other .Net developer doesn't just create a proxy of their own?
In all honesty, I'm amazed that Microsoft even allows the System.Diagnostocs.Process to be used in a .Net application. You can literally do anything you want with it, including launching the cmd shell and executing system commands. Therefore, I'd urge you to seriously consider if this is truly necessary to do. You may be better served installing vnc or using remote desktop, or another app for remote access.
One other question you need to answer is "should the application be visible to the user on that remote machine?" If so, then you need to ensure that the service is set up to run under that user's context. otherwise, you could, for example, launch Word using the local system account, and it would never be visible to the person logged into that machine.

Windows Service Application Controller

Here is the premise:
I have a desktop that I need to be able to start up and stop applications on, but cannot get remote access to. What I had in mind is setting up a service on the machine that will start/stop a list of applications as told. This windows service will periodically pole a web service for new commands and execute them accordingly.
These are my questions.
1) Is this the easiest solution? What else would you recommend?
2) How hard is it to run an exe from a windows service? How about stopping one?
This isn't for a project or anything, just something I am interested in implementing (mostly for fun). Any answers or even thoughts are appreciated. General discussion is also welcome (feel free to leave comments).

As for creating the Windows service itself in C#, see my post here.
The polling mechanism would work, but in general, I prefer event-driven processes instead of polling processes. You didn't mention what version of .NET you were using, but if it is .NET 3.0/3.5, I would suggest using WCF. When the command is posted to the web service, the web service could send the command to the Windows service to be executed. Pretty straightforward. Juval Lowy, the author of Programming WCF Services, offers a bunch of WCF examples/libraries that are free to use at his website.

So I guess PsExec is out of question?
Other than that, it's not hard to implement running of programs inside a Win service. Simply use the .NET Process class to do it, sample from my code:
ProcessStartInfo processStartInfo = new ProcessStartInfo (programExePath, commandLineArgs);
consoleLogger.WriteLine (log, Level.Debug, "Running program {0} ('{1}')", programExePath, commandLineArgs);
processStartInfo.CreateNoWindow = true;
processStartInfo.ErrorDialog = false;
processStartInfo.RedirectStandardError = true;
processStartInfo.RedirectStandardOutput = true;
processStartInfo.UseShellExecute = false;
using (Process process = new Process ())
{
process.StartInfo = processStartInfo;
process.ErrorDataReceived += new DataReceivedEventHandler (process_ErrorDataReceived);
process.OutputDataReceived += new DataReceivedEventHandler (process_OutputDataReceived);
process.Start ();
process.BeginOutputReadLine ();
process.BeginErrorReadLine ();
if (false == process.WaitForExit ((int)TimeSpan.FromHours(1).TotalMilliseconds))
throw new ArgumentException("The program '{0}' did not finish in time, aborting.", programExePath);
if (process.ExitCode != 0)
throw new ArgumentException ("failed.");
}

I have done a service that starts other exe files. There are some things to consider: As a service you have no visual desktop -> no direct interaction is possible. Also, the program must be designed to run a long while.
Stopping an exe is to kill the process. Consider the usual side-effects.

It wouldn't be too difficult - you can just have it poll some webservice for a list of "banned" applications every so often, and then on another timer, have it check for a banned application that's running and kill it if it is. Here's some code to get a list of processes, and you can use the methods on the process class to launch or kill something:
http://www.vbdotnetheaven.com/UploadFile/prvn_131971/machineprocessvb11182005001454AM/machineprocessvb.aspx
The timers could run independently as well - it can check the webservice once/day for a new add/prohibited list, but then check the processes running on the computer every 2 minutes, for example.

I'll answer question 2 first:
To start or stop programs, you just need to use the System.Diagnostics.Process object, and the example code is right in the MSDN library.
For question 1:
You could have it poll a web service periodically if you want to do that.
As an alternate, you can set up the service for remoting and have it just listen on a tcp port for function calls, then write a Windows app that can use remoting to call the service. I've had to do this for a legitimate business app and it works very well.
However, I would be very irresponsible if I didn't include this warning:
Either way, setting up a computer so that it can execute arbitrary code is a bad idea and should be done very carefully. Just because it can be done doesn't mean it should be done. If you go the web service route, how are you going to ensure that someone doesn't tamper with the web service and get malicious code to execute? How do you know someone won't mess with your app.config and point the app to their own web service? In the remoting scenario, how to you ensure that some other .Net developer doesn't just create a proxy of their own?
In all honesty, I'm amazed that Microsoft even allows the System.Diagnostocs.Process to be used in a .Net application. You can literally do anything you want with it, including launching the cmd shell and executing system commands. Therefore, I'd urge you to seriously consider if this is truly necessary to do. You may be better served installing vnc or using remote desktop, or another app for remote access.
One other question you need to answer is "should the application be visible to the user on that remote machine?" If so, then you need to ensure that the service is set up to run under that user's context. otherwise, you could, for example, launch Word using the local system account, and it would never be visible to the person logged into that machine.