Unable to connect to MongoDB Atlas using Vert.x MongoClient - mongodb

I'm trying to connect to a MongoDB database hosted in MongoDB Atlas using Vert.x MongoClient:
I'm creating MongoClient with this code (Kotlin):
MongoClient.create(vertx, jsonObjectOf(
"connection_string" to "mongodb+srv://<username>:<password>#<cluster_address>/my_db"
))
(with real values, obviously)
But I'm unable to perform any operation agains database. I get a connection timeout error:
com.mongodb.MongoTimeoutException: Timed out after 30000 ms while
waiting for a server that matches
ReadPreferenceServerSelector{readPreference=primary}. Client view of
cluster state is {type=REPLICA_SET,
servers=[{address=<server1_address>, type=UNKNOWN, state=CONNECTING},
{address=<server2_address>, type=UNKNOWN, state=CONNECTING},
{address=<server3_address>, type=UNKNOWN, state=CONNECTING}]
If I try to connect using mongosh (CLI tool) and MongoDB Compass using the same connection string, it works fine.
I have tried confguring the client with parameters (hosts, ports, etc...) instead of using a connection string and I get this error when I make a query:
MongoSocketReadException: Prematurely reached end of stream

After 11 days struggling with this, I have just solved it.
I have included "trustAll" : true option when creating MongoClient and it's working now. It's not the best solution, but anyway...

Related

Azure Cosmos DB - intermittent MongoConnectionException / IOException / SocketException

I'm using Azure Cosmos DB 4.0 with MongoDB C# Driver 2.10.4.
Most of the times the queries work fine, but I'm getting intermittent errors like this:
MongoDB.Driver.MongoConnectionException: An exception occurred while sending a message to the server.
System.IO.IOException: Unable to write data to the transport connection: An existing connection was forcibly closed by the remote host.
System.Net.Sockets.SocketException: An existing connection was forcibly closed by the remote host
at System.Net.Sockets.Socket.BeginSend(...
at System.Net.Sockets.NetworkStream.BeginWrite
--- End of inner exception stack trace ---
at System.Net.Sockets.NetworkStream.BeginWrite
at System.Net.Security._SslStream.StartWriting
at System.Net.Security._SslStream.ProcessWrite
at System.Net.Security._SslStream.BeginWrite
When that error happens the call takes 10-25 seconds before failing.
I'm building the MongoClient with new MongoClient(MongoClientSettings.FromConnectionString(cnstr)) and I was using the connectionstring with these arguments ?ssl=true&replicaSet=globaldb&retrywrites=false.
I tried with retryWrites=true (as per Azure Support suggestion) but that didn't help.
I tried different settings and that didn't work either (connect=direct, maxIdleTimeMS=30000, serverSelectionTimeout=5000ms, socketTimeout=10000ms).
What's causing those exceptions?
The fix was to set/force TLS 1.2 (based on this Microsoft document):
//return new MongoClient(connectionString);
var settings = MongoClientSettings.FromConnectionString(connectionString);
settings.SslSettings = new SslSettings()
{
EnabledSslProtocols = System.Security.Authentication.SslProtocols.Tls12
};
return new MongoClient(settings);
Looks like although my connection string had ssl=true, it wasn't enough to work on some servers (the error is intermittent). The same underlying error can usually be fixed by forcing TLS 1.2 so I assumed that in Mongo it could be the same issue - and it really fixed the problem.

strapi mongo flutter app connection error

When I install strapi via npm, then run "strapi new server" and then try to connect to mongodb atlas; It shows the following error.
(node:12564) DeprecationWarning: current Server Discovery and Monitoring engine is deprecated, and will be removed in a future version. To use the new Server Discover and Monitoring engine, pass option { useUnifiedTopology: true } to the MongoClient constructor.
⛔️ Connection test failed: failed to connect to server [oriapp-shard-00-01.pjvsw.mongodb.net:27017] on first connect [MongoNetworkError: connection 5 to oriapp-shard-00-01.pjvsw.mongodb.net:27017 closed
at TLSSocket. (C:\Users\Sharm\AppData\Local\Temp\strapi236c8a243294\node_modules\strapi-connector-mongoose\node_modules\mongodb\lib\core\connection\connection.js:356:9)
at Object.onceWrapper (events.js:422:26)
at TLSSocket.emit (events.js:315:20)
at TLSSocket.EventEmitter.emit (domain.js:483:12)
at net.js:674:12
at TCP.done (_tls_wrap.js:567:7) {
[Symbol(mongoErrorContextSymbol)]: {}
}]
So , the solution to the above problem:
Reinstall strapi using npm or yarn or any other package manager.
The ip whitelist in mongodb atlas in your cluster should have the ip address of your system.
when aysnchronous function is defined use Ipv4 in place of "localhost:1337".
Thus one will be good to go.

Azure Cosmos DB Emulator : Unable to connect to MongoDb via MongoChef

After following the instructions from the following official reference "Use the Azure Cosmos DB Emulator for local development and testing", we attempted to connect to MongoDb using MongoChef using the connection string pasted below:
mongodb://localhost:C2y6yDjf5/R+ob0N8A7Cgv30VRDJIWEHLM+4QDU5DE2nQ9nDuVTqobD4b8mGGyPMbIZnqyMsEcaGQy67XIw/Jw==#localhost:10255/admin?ssl=true
But when we test the connection through MongoChef we get the error pasted below:
Connection failed.
SERVER [localhost:10255] (Type: UNKNOWN)
|_/ Connection error (MongoSocketOpenException): Exception opening socket
|____/ Socket error: Connection refused: connect
Details:
Timed out after 30000 ms while waiting to connect. Client view of cluster state is {type=UNKNOWN, servers=[{address=localhost:27018, type=UNKNOWN, state=CONNECTING, exception={com.mongodb.MongoSocketOpenException: Exception opening socket}, caused by {java.net.ConnectException: Connection refused: connect}}]
If we check the ports currently in use on our system, we do not see 10255 being used at all.
Could someone please help us understand what's wrong here.
The connection string is correct. Studio 3T has a very nasty bug - when you use From URI function while creating new connection it cuts the "+" characters that are present in the key, that's why you need to copy the key manually to the corresponding field in connection properties.
Also, make sure the Emulator is actually launched (tray area icon should be present).

Unable to connect to MongoDb using MongoClientSettings as parameter to MongoClient

I am developing a C# MVC Web API which uses MongoDb as backend.I tried connecting to my mongodb database using
MongoClient mongoClient = new MongoClient(connectionString)
where connectionstring is in format : mongodb://Username:Password#hostname.eastus.cloudapp.azure.com
Mongo db is hosted in a virtual machine in Azure.I am able to connect to the database and all works good.But I am getting frequent exceptions:
"MongoDb.driver.MongoConnectionException".An exception occurred while
receivinf a message from server--->System.IO.IOException:Unable to
read data from the transport connection : A connection attempt failed
because the connected party did not properly respond after a period of
time,......"
So after a bit of research I have learnt that Azure is killing idle connections and I have to set MaxConnectionIdleTime.
In order to set MaxConnectionIdleTime I decided to connect to Mongodb in the below way
var credential = MongoCredential.CreateCredential("dbname", "UserName", "Password");
var settings = new MongoClientSettings
{
Credentials = new[] { credential },
Server = new MongoServerAddress("HostName", 27017),
MaxConnectionIdleTime = new TimeSpan(0, 3, 0)
};
MongoClient mongoClient = new MongoClient(settings);
In this case I am using the same username,password combination given in the connection string which I used to connect before.
While trying to connect here I am getting inner Exception:
MongoDB.Driver.MongoAuthenticationException: "Unable to authenticate
using sasl protocol mechanism SCRAM-SHA-1".
"MongoDb.driver.MongoConnectionException".An exception occurred while receivinf a message from server--->System.IO.IOException:Unable to read data from the transport connection : A connection attempt failed because the connected party did not properly respond after a period of time,....
The reason behind this exception is when hosted in Azure,Azure tries to kill the idle connections but the C# driver is not aware of this.The driver tries to execute queries on the killed connections without knowing the connection is not existing.
The solution that worked out for me is to set maxIdleTimeMS=45000 in connection string.
This way driver will not use a connection which has been idle for long time.
Here is the connection string that worked out for me
connectionString="Username:Password#hostname.eastus.cloudapp.azure.com/?connectTimeoutMS=30000&socketTimeoutMS=30000&waitQueueTimeoutMS=30000&maxIdleTimeMS=45000"
I have had a similar error with my Azure hosted MongoDb (Cosmos Db). It turned out to be network settings such that I had blocked all access. Changing it to Allow access from "All networks" fixed the issue.
The error is very misleading, I would have expected a connection timeout.
A timeout occured after 30000ms selecting a server using
CompositeServerSelector{ Selectors =
MongoDB.Driver.MongoClient+AreSessionsSupportedServerSelector,
LatencyLimitingServerSelector{ AllowedLatencyRange = 00:00:00.0150000
} }. Client view of cluster state is { ClusterId : "1", ConnectionMode
: "ReplicaSet", Type : "ReplicaSet", State : "Disconnected", Servers :
[{ ServerId: "{ ClusterId : 1, EndPoint :
"Unspecified/XXXX.documents.azure.com:10255" }", EndPoint:
"Unspecified/XXXX.documents.azure.com:10255", State: "Disconnected",
Type: "Unknown", HeartbeatException:
"MongoDB.Driver.MongoConnectionException: An exception occurred while
opening a connection to the server. --->
MongoDB.Driver.MongoAuthenticationException: Unable to authenticate
using sasl protocol mechanism SCRAM-SHA-1. --->
MongoDB.Driver.MongoCommandException: Command saslContinue failed: Not
Authenticated.
To troubleshot I tried from MongoDb Compass as well and that didn't work either, showing me it wasn't the code.

mongodb grails simple application times out

I'm having an issue with mongodb 2.6.5 and grails 2.4.4 that I can't resolve. For the sake of isolating the problem I created a simple 2.4.4 grails app, installed the grails mongodb plugin (compile ":mongodb:3.0.2"), commented out the hibernate dependencies, added my mongodb datasource, and set up a simple domain class (com.nerds.Nerd). When I generate-all and then start the app and navigate to the NerdController CRUD page I get the following error every time:
MongoTimeoutException occurred when processing request: [GET] /MONGO/nerd/index
Timed out while waiting to connect after 10000 ms. Stacktrace follows:
com.mongodb.MongoTimeoutException: Timed out while waiting to connect after 10000 ms
I can access mongo via http using http://localhost:28017/
I have also tested manually adding data and querying from mongo. This all works fine.
In the debug log prior to the timeout it looks like GORM aquired a mongo session and then tried rolling back a transaction.
DatastoreTransactionManager:128 - Found thread-bound Session [org.grails.datastore.mapping.mongo.MongoSession#e47ee6] for Datastore transaction
DatastoreTransactionManager:128 - Creating new transaction with name [null]: PROPAGATION_REQUIRED,ISOLATION_DEFAULT,readOnly
DatastoreTransactionManager:128 - Initiating transaction rollback
DatastoreTransactionManager:128 - Rolling back Datastore transaction on Session [org.grails.datastore.mapping.mongo.MongoSession#e47ee6]
DatastoreTransactionManager:128 - Resuming suspended transaction after completion of inner transaction
Any insight would be helpful. Thanks
edit: The mongo datasource is pretty simple. I'm using the correct port.
From the mongo log:
014-11-18T13:10:13.388-0900 [initandlisten] MongoDB starting : pid=17275 port=27017 dbpath=/var/lib/mongodb 32-bit host=enterprise
from DataSource.groovy
grails { mongo { host = 'localhost' port = 27017 databaseName = 'mydb' } }
I'm fairly certain the issue was on the mongod side. I stopped the mongo daemon, put it into high verbose debug mode (using mongod -vvvv command), and when I tried to replicate the issue while watching the console output, the issue did not happen. I'm not entirely sure what the exact cause of the timeout was, but its not happening now. Thanks for the responses.