A timeout occured after 30000ms selecting a server using CompositeServerSelector

Question

I try to deploy my Mongo database in Mongolabs, everything works fine, and I create a new database. Please see my connectionstring.

    public DbHelper()
    {

        MongoClientSettings settings = new MongoClientSettings()
        {
            Credentials = new MongoCredential[] { MongoCredential.CreateCredential("dbname", "username", "password") },
            Server = new MongoServerAddress("ds011111.mongolab.com", 11111),
            //ConnectTimeout = new TimeSpan(30000)
        };

        Server = new MongoClient(settings).GetServer();

        DataBase = Server.GetDatabase(DatabaseName);

    }

but when I try to connect the database it's shows error like:

enter image description here

Yeah, I have mistaken in connection string building, so the timeout error occurred. Please see the answer below. — Ragesh P Raju, Jul 17 '15 at 03:59
Possible duplicate of [MongoDB C# 2.0 TimeoutException](https://stackoverflow.com/questions/29832622/mongodb-c-sharp-2-0-timeoutexception) — kenorb, Oct 18 '17 at 14:33
I had this error because the port in my connection string did not match the port in my local mongo db configuration and settings. Once they matched, this error ceased. — AussieJoe, Mar 12 '21 at 23:14

score 33 · Answer 1 · edited May 23 '17 at 11:54

Add "?connect=replicaSet" to the end of your connection string if connecting to MongoLab.

new MongoClient("mongodb://username:password@ds011111.mongolab.com:11111/db-name?connect=replicaSet")

This JIRA ticket has some details: https://jira.mongodb.org/browse/CSHARP-1160

Basically the default is to connect to a replica set member. But MongoLab's Single-Node settings are actually a single node replica set and this causes us to not trust it. Appending ?connect=replicaSet to your connection string will force the driver to move into replica set mode and all will work.

Found that info here.

score 23 · Accepted Answer · edited Jun 10 '18 at 13:35

23

I am replacing the connection string method in like below.

new MongoClient("mongodb://username:password@ds011111.mongolab.com:11111/db-name")

Now it's solved.

Please see the answer from Paul Lemke.

edited Jun 10 '18 at 13:35

halfer

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answered Jul 17 '15 at 04:04

Ragesh P Raju

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2

Yep, MongoLab doesn't like new `MongoSettings(new MongoUri("..."))` – Chris S Aug 08 '16 at 20:17
1

Why didn't you mark his answer as the solution? – Rodrigo Reis Jul 10 '21 at 03:57

score 18 · Answer 3 · answered Apr 22 '19 at 19:37

18

Make sure your current ip address is white-listed in mongo db server. If you change your internet provider new IP needs to be white-listed.

answered Apr 22 '19 at 19:37

pankaj upadhyay

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@RamyDeeb Its not just for the user who posted it , but also for those who are facing similar issues and viewing relevant answers – Komal Bansal Jun 18 '20 at 09:20
@RamyDeeb the answer provided its also for others who has the same issue and can look for other possible solutions. Please, if you ever have another "solution", just add it, this platform is what it was built for! – Gabriel Andrés Brancolini Mar 12 '21 at 15:52
exactly what happened with my azure service... – Vitaliy Markitanov Sep 29 '22 at 19:50

score 7 · Answer 4 · answered Jun 18 '18 at 11:38

7

Make Sure your auth db is set correctly.

I ran into this issue when I mentioned only the DB i wanted to connect to , and my auth db was different (other than admin db ).

The db-name in this line is considered as the auth DB .

new MongoClient("mongodb://username:password@ds011111.mongolab.com:11111/db-name?connect=replicaSet")

Then you can change the selected DB Later

mDb = mClient.GetDatabase(mongoDBName);

answered Jun 18 '18 at 11:38

vikky MCTS

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What is the `connect` parameter in your connection string? I cannot find info on that in the Mongo docs. – mnj Dec 02 '22 at 12:57

score 5 · Answer 5 · answered Mar 28 '18 at 18:26

Same Error Message but not encountered with a MongoLabs deployment.

I just encountered the same error listed in the title with an Asp.Net Core App. My issue was due to an IOC configuration issue.

In my IOC container, my wrapped MongoClient instance was configured with a dependency transient lifestyle.

Per The MongoDb C# Driver:

It is recommended to store a MongoClient instance in a global place, either as a static variable or in an IoC container with a singleton lifetime.

I promoted the lifestyle of my object to a singleton and it resolved the issue.

I am using:

.Net Core 2.0
Mongo C# Driver version 2.5
Castle Windsor for my IOC version 3.3.0

Please reference the C# Driver Client section: http://mongodb.github.io/mongo-csharp-driver/2.5/reference/driver/connecting/#re-use

score 3 · Answer 6 · edited Jun 10 '18 at 13:36

3

Make sure the database username is also case sensitive. I ran into this issue because of case sensitivity of the username.

edited Jun 10 '18 at 13:36

halfer

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answered Jan 22 '16 at 17:30

Ramakrishna

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score 3 · Answer 7 · answered Apr 19 '20 at 18:38

It's related with MongoDB connection error. Probably you don't have permissions or you didn't specify the allowed IPs in MongoDB. Please check for example in MongoDB Compose if you are able to connect with your MongoDB Atlas. If you won't be able to connect, that means that you have wrong MongoDB connection string.

score 2 · Answer 8 · answered Apr 11 '22 at 21:56

2

In my case, while trying to execute the application with docker compose, I forget the environment variables. The problem was resolved by adding the correct environment variables.

answered Apr 11 '22 at 21:56

arakakivl

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What environment variables have you added? – tometchy Dec 16 '22 at 11:52
Those related to database connection and ASP NET environment, as I remember from now. Seeing the project now, I can see two: one of them is from MongoDb database connection; the another one is present in the main Docketfile, in API layer: `ENV ASPNETCORE_URLS=http://+:5223` – arakakivl Dec 22 '22 at 01:08

score 1 · Answer 9 · answered Sep 16 '20 at 08:35

I had the same issue. I was able to connect to MongoDB Atlas Using MongoDb Compass, but using the same connection string in a C# project I got the error "A timeout occured after 30000ms selecting a server using CompositeServerSelector... ---> System.Net.Internals.SocketExceptionFactory+ExtendedSocketException (61): Connection refused 192.168.1.254:53".

In my case the problem was caused by my Internet provider router. Switching the connection to my iPhone's 4G hotspot solved the connection issue.

score 1 · Answer 10 · answered Apr 29 '21 at 12:58

1

The port 10255 was blocked by my Internet provider/firewall rules. Opening this port at client side fixed the issue.

answered Apr 29 '21 at 12:58

ShivamShrey

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score 0 · Answer 11 · answered Jan 23 '20 at 10:57

0

I had this issue and turned out the database server was 2 hours behind. Once I fixed its time, the timeout issue was resolved with it.

answered Jan 23 '20 at 10:57

Sohail Ahmed

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score 0 · Answer 12 · answered Jul 18 '23 at 07:48

I had the same issue where there is a replicaset with name rs0 and I didnt specify the replicaset

So this caused the CompositeServerSelector timeout.

"ConnectionString": "mongodb://server01:27017,server02:27017,server03:27017"

And this

"ConnectionString": "mongodb://server01:27017,server02:27017,server03:27017?connect=replicaSet"

Passing the actual replicaset name fixed it:

"ConnectionString": "mongodb://server01:27017,server02:27017,server03:27017?replicaSet=rs0"

A timeout occured after 30000ms selecting a server using CompositeServerSelector

12 Answers12

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