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7
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0answers
3k views

Mongodb incremental backups

I was given the task to setup incremental backups for mongodb replicaset, as start point of course I googled about it and could not find anything on mongodb docs, I did find however this question ...
6
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0answers
281 views

Sudden Mongodb high connections/queues, db stops responding

The issue We have a strange issue on our mongodb setup. Sometimes we get peaks of high connections and high queues and the mongodb process stops responding if we let the queues and connections ...
3
votes
0answers
42 views

How to assign 'findandmodify' privilege to a mongo user?

I'm running a Mongo 2.6 replica instance where a node application needs to talk to. Basically nothing much was setup except these parameters: # where to write logging data. systemLog: destination: ...
3
votes
0answers
71 views

Read replica setting giving error “No candidate servers found”

I am running my website with Laravel 5 + MongoDB. I am using mongo cluster to speed up data read and write, and to lower CPU usage of the mongo server. I have set up the replica like this: 10.0.1....
3
votes
0answers
55 views

AS/400 + DB2 to MongoDB?

I'm not seeing a whole lot of info on the subject, so I figured I'd ask people who might know more about it than I do: Is it possible to replicate data from an AS/400 + IBM DB2 instance to MongoDB? If ...
3
votes
0answers
101 views

Very slow MongoDB find query

I am having troubles with this simple query which takes a few minutes. db.data_items.find({'observation_target.observation_target_id': 2190}).limit(20000) The explain output shows that the query ...
3
votes
0answers
668 views

Mongo not using enough RAM, and is slow

Our Production Mongo appears to be behaving weirdly. As far as I have read, Mongo should eat up all the available RAM to cache Index and Data in memory but in our case it is not doing so. Our ...
3
votes
0answers
170 views

automated data sync after Primary node is down

I have this scenario, using version 2.2.2: Node A, Primary, Priority: 10, Wireless network Node B, Secondary, Priority: 9, VM Server1 Node C, Secondary, Priority: 8, VM Server1 Sequence: In Node ...
2
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0answers
74 views

mongod crashes with “Invariant failure getExtent( a )->xprev.isNull()” message

I am trying to start a mongodb server with the database, that is located on portable drive. I know barely nothing about the internals of this particular database. There are 647 database.N files, 2G ...
2
votes
0answers
1k views

Multiple IPs are not getting bind in mongodb conf file

I am trying to bind multiple IP to mongodb config file, one is 0.0.0.0 and other is 127.0.0.1. I did the following change in configuration file /etc/mongod.conf # network interfaces net: port: ...
2
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0answers
27 views

how to convert mongodb(2.4.10) startup2 to primary

I have standalone bitnami mongodb(2.4.10). The output of rs.status() command is below : rs.status() { "set" : "test", "date" : ISODate("2015-11-13T08:07:41Z"), "myState" : 5, "members"...
2
votes
0answers
30 views

Impact of adjusting Time of Mongodb server?

Using Ubuntu 14.04 and mongodb 2.6.10 I have time difference between a replica machine and primary , my secondary isn't configured with NTP what are the implications of adjusting time on the ...
2
votes
0answers
22 views

Should mongodb be run in a service, or a worker cluster?

I'm trying to implement an architecture that's similar to the coreos's production architecture (shown below) Should I run the database as a central service or one or more of the workers? I figured ...
2
votes
0answers
157 views

Why is our Non-Mapped Virtual memory usage high when running MongoDB (MMAP) on CENTOS

Our non-virtual virtual memory usage on our Linux MongoDb instances seems high, currently sitting just over 2GB. The instances are running a minimal installation of CENTOS (no GUI) and they acting as ...
2
votes
0answers
123 views

MongoDB C# driver fails to reconnect after stepDown

I have an Elastic Beanstalk environment in AWS that constantly verifies the DB is accessible by querying the mongos for one document. We only speak to the DB routers and not to specific instances. ...
2
votes
0answers
373 views

Error while creating an admin user in replica set

I have a relatively simple replica set test setup between two VMs and my host machine, with VM1 as primary, VM2 as secondary and the host as arbiter. I have mongodb 2.6.4 installed on all machines. So ...
2
votes
0answers
863 views

Positional Operator Matching Nested Arrays Workaround?

As was just pointed out to me on stackoverflow, Positional Operator Matching Nested Arrays has yet to be made available.. I need to display read.marked:true replies differently than read.marked:false ...
2
votes
0answers
413 views

MongoDB communication issues on Azure

I have a Python uWSGI app running behind Nginx using pymongo to communicate with a 4 machine replica set running Mongodb 2.6.3. The replica set is configured using domain names for each machine mdb-0[...
2
votes
0answers
731 views

Error to connect mongos when trying to create replicated sharded cluster

I'm trying to create an replicated sharded cluster in mongodb. Initially I've created two shards and there are a replica set with three members in each shard. And all the shards and replicasets run in ...
2
votes
0answers
561 views

Restore backup to staging replica set

I have a staging environment with Mongo replica set which I refresh on a regular basis. Refresh is done automatically using a bash script. Staging replica set consists of 3 members (primary, ...
2
votes
0answers
2k views

“Host has low open file limits” error in MMS

I am running Standalone MongoDB (v 2.6.0 64-bit) host on Centos (v 6.5). Centos is guest OS on Windows 7 host running under VirtualBox (4.3.10). MongoDB process runs under root account. And it is ...
2
votes
0answers
367 views

MongoDB Sharding and Replica Set Allocation

I am going to setup MongoDB cluster: 3 config servers, 3 routing servers, 2 shards (replica set per shard). A replica set is just simply 1 primary, 1 secondary and 1 arbiter. Therefore, in my ...
2
votes
0answers
100 views

mysql vs mongodb cache/load balancing

I have a system where users can 'like' content. There will likely be many hundreds of these likes going on at once. I'd like it to be AJAX driven so you get an immediate response. At the moment I ...
2
votes
0answers
205 views

MongoDB secondary heartbeat hangs

We have got the same issue in two replica sets in AWS cloud. According to rs.status() on primary secondary jumping between SECONDARY and unhealthy states. With period of 10-20 seconds. In logs I see ...
2
votes
0answers
386 views

Store large hierarchy in NoSQL each day and compare

I'm in the process of creating a utility that stores a fairly large hierarchy into a NoSQL document. The data of this is similar to an Active Directory / LDAP structure which contains sub groupings, ...
1
vote
0answers
12 views

Replication prioroty

I have two MongoDB instances running on two servers (instance1 and instance2) and they are configured as a replica set. Instance1 is the primary and instance2 is the secondary. When instance1 was ...
1
vote
0answers
36 views

How to improve performance of this aggregate query?

I have the following tables in MongoDB: Users table (count 200+ users): { "_id" : ObjectId("56dd6204ce47a3c44d8b4567"), "u_role" : "1", "u_fname" : "dsfsd", "u_lname" : "dsfdsf", "u_email" : "dsfds@...
1
vote
0answers
47 views

Progress of mongodump operation jams at a random point

We are executing remote mongodumps to backup collections. For some time now sporadically one of these dumps stops to progress any further and remains to log out the same amount of documents processed ...
1
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0answers
44 views

MongoDB insert not replicating after db.dropDatabase()

I'm new to MongoDB (inherited a project using it), so this is especially confusing. I have a sharded replicaset between 3 ec2 instances. Everything works fine until I drop a database. The database ...
1
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0answers
52 views

Mongos process memory usage and crashes

So our MongoS instances use up A LOT of memory. More than even the shards and sometimes crash because of it. Cluster structure 3x mongos 3x mongod Shards 3x mongod Replicas (one for each shard) 3x ...
1
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0answers
39 views

Replacing a member of a replica set with the same host name

I am replacing a member of a replica set (the new member has a different IP address). What I am looking to do is as follows: RSYNC the data directory of the existing secondary node to the new node. ...
1
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0answers
26 views

Operational issue for scheduling mongodump as backup method

For production backup, MongoDB recommends mongodump instead of mongoexport for accuracy of data. However, a few operational issue remain unclear to me, appreciate if anyone can advise on this matter. ...
1
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0answers
25 views

Mongo is slow when the IOPS reaches 50%

We have an AWS-r3.large system. With 1.5TB data volume dedicated to Mongo. We are still using 2.6.3 (yes, upgrade pending for a while now). The data size is only 550GB. The volume that we have, has ...
1
vote
0answers
75 views

Why switch? [ReplicationExecutor] another primary seen with election time xxx:1 my election time is yyy:1

On 09-05-16 - 08:41:51 Replica Set elected a new primary. The question why? Here the logs from this time series and without login messages egrep -v 'NETWORK|ACCESS'. On the same OpenStack platform ...
1
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0answers
30 views

Solr with SQL Server or NoSQL

I am working on a POC of using Solr with SQL Server. I have a very complex data model with SQL server which required a bunch of joining and scalar functions to strip some mark up and other stuff. ...
1
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0answers
80 views

Getting empty folder when using mongodump to back up my MongoDB

Basically, I have a problem with using mongodump to back up my MongoDB. This is the general syntax I use in SSH: mongodump -d myDatabaseName -o ~/backups/my_backup This is the resulting message: ...
1
vote
0answers
82 views

Understanding MongoDB Log warning

In my MongoDB log, I am seeing these lines of messages: 2016-04-05T00:03:42.904+0000 I COMMAND [ftdc] serverStatus was very slow: { after basic: 200, after asserts: 240, after backgroundFlushing: ...
1
vote
0answers
40 views

Running a query in Mongo Shell vs PyMongo (in Flask) results in extreme slowdown

When prototyping a query I've been using just the Mongo Shell to make sure my aggregation query is working fine: # Default query query = [{ # Supposedly forces MongoDB to initially use ...
1
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0answers
90 views

MongoDB with multi core instance

I have a "large" EC2 instance with 2 cores running MongoDB as part of a Replicaset. Does MongoDB use both cores in parallel by default or do I need to make some configuration change?
1
vote
0answers
34 views

Mongo indexes question

I have the following aggregation query: db.getCollection('usersongs').aggregate([ {$match: { room: 'someObjId', status: { $in: [ "ended", "skipped" ] } } }, {$group: { ...
1
vote
0answers
18 views

MongoDB Fails to get TGT

I've setup MongoDB enterprise on CentOS 7 with Kerberos support. Additionally I've setup a Kerberos service on CentOS 7 for the authentication. I know that Kerberos is setup correctly as I now have ...
1
vote
0answers
43 views

Would it be good practice to represent MongoDB ObjectId as a String or a Blob type in SQL Lite (RDMS world)?

All: We have a software application with 1) Web-based component 2) Mobile-based component Our 1) Web-based component uses a) MongoDB as the Database b) ASP.NET C# Our 2) Mobile-based component ...
1
vote
0answers
42 views

MongoDB:Too many connections from Secondary

We have a 3 node replica set running on MongoDB 3.2, and having an issue with Replication. On Primary server, connection count will keep increasing as one of the secondary will keep making new ...
1
vote
0answers
56 views

I can't see some databases with even though my user has the “root” role

I installed MongoDB 3.2 and I enabled authentication: security: authorization: enabled I created an admin user with the following command in the terminal: mongo admin --eval 'db.createUser({user:...
1
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0answers
32 views

efficient way to store immutable numeric data

I'm trying to put a bunch of worldwide climate data into some kind of database structure so I can quickly access a collation of all 10 datasets simultaneously with fast indexing and hopefully ...
1
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0answers
23 views

ConfigServersInconsistent:How to correct the inconsistency?

Detected that the one of the config servers is inconsistent with rest two, in a 3 config-server environment. But not sure how to set this right. I have gone through mongodb config servers not in sync ...
1
vote
0answers
85 views

Adding a Mongo Shard decreases the insert performance

For a mobile application which will hold quite some documents, we've chosen Mongo as a database. Let me explain the situation first: Every day, I have a set of documents that needs to be inserted, ...
1
vote
0answers
18 views

Syncing writes and not deletes - mongoDB

Is it possible to have a secondary instance of mongoDB which syncs all the write operations to the database and not the delete operation? I'm looking for this solution so that I have a backup even if ...
1
vote
0answers
61 views

How to Shard a Mongodb Collection based on String and Date Time Shard Key using Range Based Sharding

I am new to Mongodb,I have to Shard a Collection Based on Integer, String and Date time shard key, I am able to shard a collection using integer shard key. below is the command,I am using for Range ...
1
vote
0answers
26 views

Security: direct remote access vs webinterface

I need to remotely connect to my (mongoDB) database and I currently allow direct access to the DB server port with user/pw login. I often read that this is generally a bad idea and that one should ...