I have a REST service built in node.js with Restify and Mongoose and a mongoDB with a collection with about 30.000 regular sized documents. I have my node service running through pmx and pm2.
Yesterday, suddenly, node started crapping out errors with the message "MongoError: Topology was destroyed", nothing more. I have no idea what is meant by this and what could have possibly triggered this. there is also not much to be found when google-searching this. So I thought I'd ask here.
After restarting the node service today, the errors stopped coming in. I also have one of these running in production and it scares me that this could happen at any given time to a pretty crucial part of the setup running there...
I'm using the following versions of the mentioned packages:
You need to restart mongo to solve the topology error, then just change some options of mongoose or mongoclient to overcome this problem:
var mongoOptions = {
useMongoClient: true,
keepAlive: 1,
connectTimeoutMS: 30000,
reconnectTries: Number.MAX_VALUE,
reconnectInterval: 5000,
useNewUrlParser: true
}
mongoose.connect(mongoDevString,mongoOptions);
I know that Jason's answer was accepted, but I had the same problem with Mongoose and found that the service hosting my database recommended to apply the following settings in order to keep Mongodb's connection alive in production:
var options = {
server: { socketOptions: { keepAlive: 1, connectTimeoutMS: 30000 } },
replset: { socketOptions: { keepAlive: 1, connectTimeoutMS: 30000 } }
};
mongoose.connect(secrets.db, options);
I hope that this reply may help other people having "Topology was destroyed" errors.
In my case, this error was caused by a db.close(); out of a 'await' section inside of 'async'
MongoClient.connect(url, {poolSize: 10, reconnectTries: Number.MAX_VALUE, reconnectInterval: 1000}, function(err, db) {
// Validate the connection to Mongo
assert.equal(null, err);
// Query the SQL table
querySQL()
.then(function (result) {
console.log('Print results SQL');
console.log(result);
if(result.length > 0){
processArray(db, result)
.then(function (result) {
console.log('Res');
console.log(result);
})
.catch(function (err) {
console.log('Err');
console.log(err);
})
} else {
console.log('Nothing to show in MySQL');
}
})
.catch(function (err) {
console.log(err);
});
db.close(); // <--------------------------------THIS LINE
});
I got this error, while I was creating a new database on my MongoDb Compass Community. The issue was with my Mongod, it was not running. So as a fix, I had to run the Mongod command as preceding.
C:\Program Files\MongoDB\Server\3.6\bin>mongod
I was able to create a database after running that command.
Hope it helps.
I was struggling with this for some time - As you can see from other answers, the issue can be very different.
The easiest way to find out whats causing is this is to turn on loggerLevel: 'info' in the options
"Topology was destroyed" might be caused by mongoose disconnecting before mongo document indexes are created, per this comment
In order to make sure all models have their indexes built before disconnecting, you can:
await Promise.all(mongoose.modelNames().map(model => mongoose.model(model).ensureIndexes()));
await mongoose.disconnect();
I got this problem recently. Here what I do:
sudo service mongod restartpm2 restart [your-app-id]. To get ID use pm2 listHere what I did, It works fine. Issue was gone after adding below options.
const dbUrl = "mongodb://localhost:27017/sampledb";
const options = { useMongoClient: true, keepAlive: 1, connectTimeoutMS: 30000, reconnectTries: 30, reconnectInterval: 5000, useNewUrlParser: true }
mongoose.connect(dbUrl,options, function(
error
) {
if (error) {
console.log("mongoerror", error);
} else {
console.log("connected");
}
});
This error is due to mongo driver dropping the connection for any reason (server was down for example).
By default mongoose will try to reconnect for 30 seconds then stop retrying and throw errors forever until restarted.
You can change this by editing these 2 fields in the connection options
mongoose.connect(uri,
{ server: {
// sets how many times to try reconnecting
reconnectTries: Number.MAX_VALUE,
// sets the delay between every retry (milliseconds)
reconnectInterval: 1000
}
}
);
I met this in kubernetes/minikube + nodejs + mongoose environment. The problem was that DNS service was up with a kind of latency. Checking DNS is ready solved my problem.
const dns = require('dns');_x000D_
_x000D_
var dnsTimer = setInterval(() => {_x000D_
dns.lookup('mongo-0.mongo', (err, address, family) => {_x000D_
if (err) {_x000D_
console.log('DNS LOOKUP ERR', err.code ? err.code : err);_x000D_
} else {_x000D_
console.log('DNS LOOKUP: %j family: IPv%s', address, family);_x000D_
clearTimeout(dnsTimer);_x000D_
mongoose.connect(mongoURL, db_options);_x000D_
}_x000D_
});_x000D_
}, 3000);_x000D_
_x000D_
_x000D_
var db = mongoose.connection;_x000D_
var db_options = {_x000D_
autoReconnect:true,_x000D_
_x000D_
poolSize: 20,_x000D_
socketTimeoutMS: 480000,_x000D_
keepAlive: 300000,_x000D_
_x000D_
keepAliveInitialDelay : 300000,_x000D_
connectTimeoutMS: 30000,_x000D_
reconnectTries: Number.MAX_VALUE,_x000D_
reconnectInterval: 1000,_x000D_
useNewUrlParser: true_x000D_
};(the numbers in db_options are arbitrary found on stackoverflow and similar like sites)
I solved this issue by:
Sebastian comment on Adrien's answer needs more attention it helped me but it being a comment might be ignore sometime so here's a solution:
var options = { useMongoClient: true, keepAlive: 1, connectTimeoutMS: 30000, reconnectTries: 30, reconnectInterval: 5000 }
mongoose.connect(config.mongoConnectionString, options, (err) => {
if(err) {
console.error("Error while connecting", err);
}
});
Using mongoose here, but you could do a similar check without it
export async function clearDatabase() {
if (mongoose.connection.readyState === mongoose.connection.states.disconnected) {
return Promise.resolve()
}
return mongoose.connection.db.dropDatabase()
}
My use case was just tests throwing errors, so if we've disconnected, I don't run operations.
Just a minor addition to Gaafar's answer, it gave me a deprecation warning. Instead of on the server object, like this:
MongoClient.connect(MONGO_URL, {
server: {
reconnectTries: Number.MAX_VALUE,
reconnectInterval: 1000
}
});
It can go on the top level object. Basically, just take it out of the server object and put it in the options object like this:
MongoClient.connect(MONGO_URL, {
reconnectTries: Number.MAX_VALUE,
reconnectInterval: 1000
});
In my case, this error was caused by an identical server instance already running background.
The weird thing is when I started my server without notice there's one running already, the console didn't show anything like 'something is using port xxx'. I could even upload something to the server. So, it took me quite long to locate this problem.
What's more, after closing all the applications I can imagine, I still could not find the process which is using this port in my Mac's activity monitor. I have to use lsof to trace. The culprit was not surprising - it's a node process. However, with the PID shown in the terminal, I found the port number in the monitor is different from the one used by my server.
All in all, kill all the node processes may solve this problem directly.
I alse had the same error. Finally, I found that I have some error on my code. I use load balance for two nodejs server, but I just update the code of one server.
I change my mongod server from standalone to replication, but I forget to do the corresponding update for the connection string, so I met this error.
standalone connection string:
mongodb://server-1:27017/mydb
replication connection string:
mongodb://server-1:27017,server-2:27017,server-3:27017/mydb?replicaSet=myReplSet
details here:[mongo doc for connection string]
Source: Stackoverflow.com