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AWSSDK s3 .net question. My multipart upload crashes after 15mins of transfer

I'm uploading rather a lot of data (30gb+) across thousands of files. The whole process takes a while but I've been finding that consistently after 15 mins of transfers, the upload process fails and I get errors for each file that is currently being transferred (I'm doing it multithreaded so there are multiple uploads at once). The error code I'm getting is "error: Amazon.S3.AmazonS3Exception: The difference between the request time and the current time is too large. ---> Amazon.Runtime.Internal.HttpErrorResponseException: The remote server returned an error: (403) Forbidden. ---> System.Net.WebException: The remote server returned an error: (403) Forbidden."
Seeing as its exactly 15 mins from the start of the whole process that this thing crashes, I think its maybe that the client is timing out, however I've set my client's timout to 45 mins I think:
{
var client = new AmazonS3Client(new AmazonS3Config()
{
RegionEndpoint = RegionEndpoint.EUWest2,
UseAccelerateEndpoint = true,
Timeout = TimeSpan.FromMinutes(45),
ReadWriteTimeout = TimeSpan.FromMinutes(45),
RetryMode = RequestRetryMode.Standard,
MaxErrorRetry = 10
});
Parallel.ForEach(srcObjList, async srcObj =>
{
try
{
var putObjectRequest = new PutObjectRequest();
putObjectRequest.BucketName = destBucket;
putObjectRequest.Key = srcObj.Key;
putObjectRequest.FilePath = filePathString;
putObjectRequest.CannedACL = S3CannedACL.PublicRead;
var uploadTask = client.PutObjectAsync(putObjectRequest);
lock (threadLock)
{
syncTasks.Add(uploadTask);
}
await uploadTask;
}
catch (Exception e)
{
Debug.LogError($"Copy task ({srcObj.Key}) failed with error: {e}");
throw;
}
});
try
{
await Task.WhenAll(syncTasks.Where(x => x != null).ToArray());
}
catch (Exception e)
{
Debug.LogError($"Upload encountered an issue: {e}");
}
});
await transferOperations;
Debug.Log("Done!");```

The documentation doesn't specify the maximum timeout value, but given that you're seeing 15 minutes exactly, it stands to reason there is some upper limit to the timeout value, either a hard limit or something in the S3 bucket's settings.
This answer suggests a clock synchronization difference might also be the case, but then I'd wonder why the transfer starts at all.

Cannot get error 500 details in controller

I have a simple Rest Web service that raises an exception randomly (Internal Server Error).
I noticed it when I have stressed this Web api in a console program in a 50.000 iterations loop.
What I get in this client :
{StatusCode: 500, ReasonPhrase: 'Internal Server Error', Version: 1.1,
What I want is to get this Error 500 detail.
But I cannot catch it in my controller, the code doesn't go in the catch.
The controller code :
[HttpPost]
[Route("{IdLog}/message")]
public string CreateLogMsg(long IdLog, [FromBody] TlogLineDTO oLogLine)
{
long lTmp = 0;
try
{
if (ModelState.IsValid)
{
string sTmp = _oExploitBll.InsertNewLogLine(oLogLine).ToString();
if (!long.TryParse(sTmp, out lTmp))
{
// Create a new file
Random rnd = new Random();
using (System.IO.StreamWriter sw = System.IO.File.AppendText(#"E:\Temp\20200707\REF_" + rnd.Next().ToString() + ".txt"))
{
sw.WriteLine(sTmp);
}
}
return sTmp;
}
else
{
// Create a new file where to put the error message
Random rnd = new Random();
using (System.IO.StreamWriter sw = System.IO.File.AppendText(#"E:\Temp\20200707\REF_" + rnd.Next().ToString() + ".txt"))
{
sw.WriteLine("Ko");
}
return "Ko";
}
}
catch (Exception ex)
{
string sMsgErr = ex.Message + "-" + ex.StackTrace;
// Create a new file
Random rnd = new Random();
using (System.IO.StreamWriter sw = System.IO.File.AppendText(#"E:\Temp\20200707\REF_" + rnd.Next().ToString() + ".txt"))
{
sw.WriteLine(sMsgErr);
}
return "0";
}
}
How can I make it go in the catch ?
Does someone have an idea ?
Thanks a lot in advance.
Eric

If, as you say, the error happens because the server is too stressed the requests which get the error never reach the controller. Actually the server cannot even enqueue them. Sso you can't handle them unless you add a side-car server which receives requests from the client, forwards them to your server and then
if response is ok forwards response to client
else handles the error
In real case scenarios you use a load balancer to divide the request load between more servers

In fact, I have corrected the code and added a loop of 2 retries for the http requests and it seems to work : when the http request fails, I retry it once (or the number of retries I want) and generally the http request success in the second retry.
But I still don't know why the http requests fail sometimes.

How to check database connection in MongoDB [duplicate]

I use MongoDB drivers to connect to the database. When my form loads, I want to set up connection and to check whether it is ok or not. I do it like this:
var connectionString = "mongodb://localhost";
var client = new MongoClient(connectionString);
var server = client.GetServer();
var database = server.GetDatabase("reestr");
But I do not know how to check connection. I tried to overlap this code with try-catch, but to no avail. Even if I make an incorrect connectionString, I still can not get any error message.

To ping the server with the new 3.0 driver its:
var database = client.GetDatabase("YourDbHere");
database.RunCommandAsync((Command<BsonDocument>)"{ping:1}")
.Wait();

There's a ping method for that:
var connectionString = "mongodb://localhost";
var client = new MongoClient(connectionString);
var server = client.GetServer();
server.Ping();

full example for 2.4.3 - where "client.GetServer()" isn't available.
based on "Paul Keister" answer.
client = new MongoClient("mongodb://localhost");
database = client.GetDatabase(mongoDbStr);
bool isMongoLive = database.RunCommandAsync((Command<BsonDocument>)"{ping:1}").Wait(1000);
if(isMongoLive)
{
// connected
}
else
{
// couldn't connect
}

I've had the same question as the OP, and tried every and each solution I was able to find on Internet...
Well, none of them worked to my true satisfaction, so I've opted for a research to find a reliable and responsive way of checking if connection to a MongoDB Database Server is alive. And this without to block the application's synchronous execution for too long time period...
So here are my prerequisites:
Synchronous processing of the connection check
Short to very short time slice for the connection check
Reliability of the connection check
If possible, not throwing exceptions and not triggering timeouts
I've provided a fresh MongoDB Installation (version 3.6) on the default localhost URL: mongodb://localhost:27017. I've also written down another URL, where there was no MongoDB Database Server: mongodb://localhost:27071.
I'm also using the C# Driver 2.4.4 and do not use the legacy implementation (MongoDB.Driver.Legacy assembly).
So my expectations are, when I'm checking the connection to the first URL, it should give to me the Ok for a alive connection to an existing MongoDB server, when I'm checking the connection to the second URL it should give to me the Fail for a non-existing MongoDB server...
Using the IMongoDatabase.RunCommand method, queries the server and causes the server response timeout to elapse, thus not qualifying against the prerequisites. Furthermore after the timeout, it breaks with a TimeoutException, which requires additional exception handling.
This actual SO question and also this SO question have delivered the most of the start information I needed for my solution... So guys, many thanks for this!
Now my solution:
private static bool ProbeForMongoDbConnection(string connectionString, string dbName)
{
var probeTask =
Task.Run(() =>
{
var isAlive = false;
var client = new MongoDB.Driver.MongoClient(connectionString);
for (var k = 0; k < 6; k++)
{
client.GetDatabase(dbName);
var server = client.Cluster.Description.Servers.FirstOrDefault();
isAlive = (server != null &&
server.HeartbeatException == null &&
server.State == MongoDB.Driver.Core.Servers.ServerState.Connected);
if (isAlive)
{
break;
}
System.Threading.Thread.Sleep(300);
}
return isAlive;
});
probeTask.Wait();
return probeTask.Result;
}
The idea behind this is the MongoDB Server does not react (and seems to be non-existing) until a real attempt is made to access some resource on the server (for example a database). But retrieving some resource alone is not enough, as the server still has no updates to its state in the server's Cluster Description. This update comes first, when the resource is retrieved again. From this time point, the server has valid Cluster Description and valid data inside it...
Generally it seems to me, the MongoDB Server does not proactivelly propagate its Cluster Description to all connected clients. Rather then, each client receives the description, when a request to the server has been made. If some of you fellows have more information on this, please either confirm or deny my understandings on the topic...
Now when we target an invalid MongoDB Server URL, then the Cluster Description remains invalid and we can catch and deliver an usable signal for this case...
So the following statements (for the valid URL)
// The admin database should exist on each MongoDB 3.6 Installation, if not explicitly deleted!
var isAlive = ProbeForMongoDbConnection("mongodb://localhost:27017", "admin");
Console.WriteLine("Connection to mongodb://localhost:27017 was " + (isAlive ? "successful!" : "NOT successful!"));
will print out
Connection to mongodb://localhost:27017 was successful!
and the statements (for the invalid URL)
// The admin database should exist on each MongoDB 3.6 Installation, if not explicitly deleted!
isAlive = ProbeForMongoDbConnection("mongodb://localhost:27071", "admin");
Console.WriteLine("Connection to mongodb://localhost:27071 was " + (isAlive ? "successful!" : "NOT successful!"));
will print out
Connection to mongodb://localhost:27071 was NOT successful!

Here a simple extension method to ping mongodb server
public static class MongoDbExt
{
public static bool Ping(this IMongoDatabase db, int secondToWait = 1)
{
if (secondToWait <= 0)
throw new ArgumentOutOfRangeException("secondToWait", secondToWait, "Must be at least 1 second");
return db.RunCommandAsync((Command<MongoDB.Bson.BsonDocument>)"{ping:1}").Wait(secondToWait * 1000);
}
}
You can use it like so:
var client = new MongoClient("yourConnectionString");
var database = client.GetDatabase("yourDatabase");
if (!database.Ping())
throw new Exception("Could not connect to MongoDb");

This is a solution by using the try-catch approach,
var database = client.GetDatabase("YourDbHere");
bool isMongoConnected;
try
{
await database.RunCommandAsync((Command<BsonDocument>)"{ping:1}");
isMongoConnected = true;
}
catch(Exception)
{
isMongoConnected = false;
}
so when it fails to connect to the database, it will throw an exception and we can handle our bool flag there.

If you want to handle connection issues in your program you can use the ICluster.Description event.
When the MongoClient is created, it will continue to attempt connections in the background until it succeeds.
using MongoDB.Driver;
using MongoDB.Driver.Core.Clusters;
var mongoClient = new MongoClient("localhost")
mongoClient.Cluster.DescriptionChanged += Cluster_DescriptionChanged;
public void Cluster_DescriptionChanged(object sender, ClusterDescriptionChangedEventArgs e)
{
switch (e.NewClusterDescription.State)
{
case ClusterState.Disconnected:
break;
case ClusterState.Connected:
break;
}
}

FTP client, Unexpected error occurred on a receive occurs twice, then times out indefinitely

I have an FTP client, running as part of a windows service that gets information from an FTP server on a scheduled basis. My issue is that sometimes, the FTP server is down for planned maintanance. When this happens, my FTP client still calls out on a scheduled basis and fails with the following error:
System.Net.WebException. The underlying connection was closed: An unexpected error occurred on a receive
I get the error above twice. After this, I get the following timeout error every time indefinitely:
System.Net.WebException The operation has timed out
Even with the maintenance window complete, my windows service will keep timing out when attempting to connect to the FTP server. The only way we can solve the problem is by restarting the windows service. The following code shows my FTP client code:
var _request = (FtpWebRequest)WebRequest.Create(configuration.Url);
_request.Method = WebRequestMethods.Ftp.DownloadFile;
_request.KeepAlive = false;
_request.Timeout = configuration.RequestTimeoutInMilliseconds;
_request.Proxy = null; // Do NOT use a proxy
_request.Credentials = new NetworkCredential(configuration.UserName, configuration.Password);
_request.ServicePoint.ConnectionLeaseTimeout = configuration.RequestTimeoutInMilliseconds;
_request.ServicePoint.MaxIdleTime = configuration.RequestTimeoutInMilliseconds;
try
{
using (var _response = (FtpWebResponse)_request.GetResponse())
using (var _responseStream = _response.GetResponseStream())
using (var _streamReader = new StreamReader(_responseStream))
{
this.c_rateSourceData = _streamReader.ReadToEnd();
}
}
catch (Exception genericException)
{
throw genericException;
}
Anyone know what the issue might be?

SQL Server Error while pulling hundreds of records

I am getting this error when I try to get all the username password from production copied local database, I guess it is because of not closing the connection properly, but I am not sure how . I am using the Microsoft Enterprise Library, ant thought or comment about it?
Timeout expired. The timeout period elapsed prior to
obtaining a connection from the pool. This may have occurred
because all pooled connections were in use and max pool size was reached.
this is the mothod that is getting the username and password and producing the error.
private Model.UsernameandPass GetUsernamePass(string AccountNumber)
{
Model.UsernameandPass model = null;
string myConnection = System.Configuration.ConfigurationManager.ConnectionStrings[connectionName].ToString();
SqlDatabase db = new SqlDatabase(myConnection);
using (DbCommand command = db.GetStoredProcCommand("Get_TheUsernamePassWordFromProduction"))
{
db.AddInParameter(command, "AccountNumber", DbType.String, AccountNumber);
var result = db.ExecuteReader(command);
try
{
while (result.Read())
{
model = new Model.UsernameandPass();
model.Username = result.GetString(1);
model.Password = result.GetString(2);
}
}
catch (Exception ex)
{
}
}
db = null;
return model;
}
I am getting the error in this line after program runs for a while.
var result = db.ExecuteReader(command);

You're getting that error because a connection cannot be established, not only because they aren't being closed properly. Check permissions for the user you're trying to authenticate against the database with. Also be sure to call .open()/.close() when/if you are programatically opening/closing connections.
Check this link. You may want to increase your pool size, or check for long-running queries.