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196 views

How to read a bson file using C#

I have a bson file dumped by mongodump command. How can I read the content of this file to memory with C#?? I don't want to use the mongorestore command.
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1answer
95 views

Ring topology support of MongoDB ReplicaSet and Sharding?

Just curious if the following ring-like topology supported/recommended or is right for a sharded/replicaset cluster. version: mongodb 2.4.5 hosts(all vms) #[MongoDB Config] mongodb_roles="replset1 ...
3
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1answer
35 views

How to remove a corrupted shard in MongoDB

I use MongoDB 3.0.3 with Wired Tiger engine on Cent OS 6.4. I have a sharded cluster of 4 shards each of which has about a quarter of total data. One of the shard called "shard2" corrupted and can'...
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1answer
156 views

how to make secondary slave as readable in MongoDB?

How do I make a secondary slave as readable in MongoDB? We can do this via shell command rs.slaveOk() But how we can do it permanently for all session via config file?
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1answer
843 views

Unable to create replica set for MongoDB in Linux

When I run the following command: rs.initiate(), I get the following error: "info2" : "no configuration explicitly specified -- making one", "me" : "ip-10-0-2-113:27017", "ok" : 0, ...
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1answer
97 views

Mongo is using 5-7% of CPU, so why is my computer so slow? [closed]

I've installed MongoDB (not sharded, single location) on an AWS EC2 instance, and I'm finding that when I'm running large insert operations via pymongo, my entire EC2 instance gets very sluggish. Yet ...
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0answers
149 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 ...
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1answer
179 views

Good ratio for data, journal, and log drive sizes for MongoDB?

Is there a good ratio for drive sizes for MongoDB? For example if you have a 8Gig drive for the data, then how big should my drive for the log be? How about the drive for the journal? Just a little ...
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1answer
30 views

On EC2 Why do I need individual EBS volumes for journal, log, and data?

According to this MongoDB tutorial which explains how to manually deploy MongoDB on EC2, one of the steps states that you should have: "Individual PIOPS EBS volumes for data (1000 IOPS), journal (250 ...
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1answer
476 views

Mysql InnoDB vs Mongodb write performance

I need to increment a counter each time a web page is rendered. When I use mongodb to do that, I can do about 16000 writes per second on a 4 cores/8 threads CPU on a regular disk. When I use Mysql ...
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0answers
118 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. ...
3
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1answer
1k views

Mongodb high lock percentage / slow queries

I'm working with an application using MongoDB that is getting a fairly large number of incoming requests and I've noticed that the responses are getting slower as the number of requests get higher. ...
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2answers
179 views

Does the MongoDB background flush (MMAP) update the entire document even if only a small portion has changed? i.e. set on an array position

We are currently trying to get to the bottom of some high background flush times on our MongoDB installation. As part of this investigation we have been looking at the $set operation we perform on an ...
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1answer
69 views

updating single row in MYSQL

We have a situation where we need to update on a single row several thousands time a second and this requirement lasts continuously for 5 hours every day due to the nature of the business. Design ...
2
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1answer
171 views

What data structure is used for MongoDB 3.x geospatial indexes?

For the MongoDB 3.x geospatial features what structure is used for the indexes? B-tree? R-tree? X-tree? I can't find any information about the structures in their documentation
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1answer
39 views

How to index an property object in MongoDb?

i've the following sample document: { "_id" : ObjectId("556e177ca43da29e040041a7"), "user_id" : NumberLong(24), "request_datetime" : ISODate("2015-06-02T15:52:12.000-05:00"), "...
1
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1answer
159 views

mongodump with readpref nearest

I have a mongodb cluster where shards exist across multi geographically locations and each of those locations have replica members for each shard. I have setup our DR datacenter. Which also has a ...
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1answer
658 views

MongoDB denying API access, while console shell works

I am a MongoDB newbie, with a MongoDB instance running on a Ubuntu machine. If I login onto the machine's console and run mongo -u username -p password databasename I have permissions for the ...
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1answer
89 views

MongoLab: Does hardware effect performance of a find() query [closed]

I asked a pervious question on StackOverflow about if document size affected the performance of fetching that document (the document is 3MB in size) http://stackoverflow.com/questions/30226219/does-...
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1answer
2k views

cannot log in to mongo from command line - using MongoDB 3.0 and WiredTiger - I've followed all instructions

NOTE: I have tried not setting bind_ip and also setting it to 0.0.0.0 -- neither one fixed my issue. This is my mongod.conf file: systemLog: destination: file path: "/root/mongodb.log" ...
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1answer
78 views

How to force a delayed member to become primary in case of failure in mongodb

I have three member set [primary,secondary & arbiter] in my data center 1 [DC1]. Now i want a delayed member in data center 2 [DR]. In case DC 1 is completely down then my sub net application ...
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0answers
149 views

Docker Mongodb replication on different hosts is not working

I am trying to setup a mongodb replication in Docker containers running on different hosts. Please find the steps below: In a VM1 running ubuntu 14.04, installed docker, then created container C1. ...
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1answer
53 views

Running Aggregation logic on multiple shards of MongoDB

Suppose we have 5 shards in MongoDB having collection of data, and I have to write an Aggregation logic which should work on each of 5 shards in my cluster and collect data from these shards. Should ...
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1answer
88 views

MongoDB 3.0 - how do I check which storage engine is being used? [duplicate]

I have MongoDB 3.0.0 running on a Digital Ocean droplet. How can I tell which storage engine it is using?
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1answer
37 views

Understanding MongoDB Aggregation

Pretend that our collection has 1M document Now if i do aggregation like this: db.users.aggregate({ $group: { _id : "$gender", avgAge : { $avg : "$age" } } }) then how it ...
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498 views

Best way to run an ETL on a production MongoDB database

We have the following environment: 3 servers + 3 replica set servers Each server has 3 shards Our main collection has around 40,000,000 documents that average at around 6kb Our shard key is hashed(...
6
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1answer
141 views

Remove a shard in MongoDB

I have a MongoDB cluster, I accidentally hosed a shard, I don't have a backup. It's pretty easy to recover the data, but after issuing the removeShard command, it says it's draining. However, the ...
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2answers
8k views

MongoDB service not working after upgrade to Ubuntu 15.04

I have recently upgraded my Ubuntu from 14.10 to 15.04. All features seems to be working fine except MongoDB. It is not controllable from service as we do normally in Ubuntu. sudo service mongodb ...
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0answers
44 views

User with more than enough permission, cannot query collection

I'm in mongo shell. I'm authenticated as a user with way beyond enough permission to simply query a collection. Yet I cannot. Here is the user permissions... What am I doing wrong and/or missing? ...
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1answer
97 views

MongoDb replica set: How do I verify data replication on other servers?

I have a 3 member replica set running. It's geo-located on 3 separate VPSs. On primary I can do rs.status() and see it's working. I can't execute any mongo shell commands on the secondaries. How do I ...
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1answer
51 views

Can we have two primaries for the same shard in mongodb?

Can we have a Mongodb deployment in two data centers in which the data set is divided into two shards A and B. Data Center 1 | Data Center 2 Shard A, Shard B | ...
4
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1answer
547 views

Who can explain mongodb with ssl?

I created certificates according to the instructions on the official website of MongoDB, but it doesn't work properly. I have a replica set and self-signed certificates. I need a full encryption ...
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1answer
104 views

What is the difference between hadoop, mongoDB, Big data? [closed]

What is the difference between Hadoop, MongoDB, Big data ?
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2answers
457 views

export data from SQl to text file/MongoDB

I have some data in multiple tables (ACTTAB, APTTAB, ...) How do I export this data from SQL and insert into a text file? How can I import this data into MongoDB?
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1answer
62 views

Mongo primary is showing behind the primary?

Mongo primary is showing behind the primary ?? Its increasing as time passes . Please suggest ? monRepl:PRIMARY> rs.printSlaveReplicationInfo() source: xxxxxx:27017 syncedTo: Mon Apr 27 2015 ...
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1answer
107 views

Why sharding does not show any improvement?

Here is what I did to test sharding performance. I have 4 servers, I ran config server and router on a server. 3 others are meant to be shards. First, I only added one shard to router, then I ran a ...
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1answer
139 views

Mongo Shard with Negative Average Size? [closed]

I'm seeing the following behavior from a shard in mongo: mongos> db.fs.chunks.getShardDistribution() Shard SH0 data : 740.29GiB docs : 5003098 chunks : 32949 estimated data per chunk : 23MiB ...
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0answers
613 views

Creating Pandas DataFrame on Python From a MongoDB Document containing Embedded documents

I am working on a machine learning algorithm on python's scikit.learn, but this time the data are in Mongodb documents format. I would like to pull my data into a dataframe. Here is an exemple of the ...
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22 views

Mongodb: How to resolve startup2 state

I have a shard cluster. Each shard consists of a replication set with one Primary node and an arbiter node. There is a large number of data in each shard. The host of a Primary of a shard crashed ...
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1answer
66 views

How can I create a MongoDB based on MySQL schema?

How can I create a MongoDB based on MySQL schema? This is my schema: productCode VARCHAR(15) productName VARCHAR(70) productLine VARCHAR(50) productScale VARCHAR(10) productVendor VARCHAR(50) ...
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1answer
188 views

MongoDB “overacts” on cleaning/flushing and finally hangs up

Recently I run several times into trouble with mongodb that exhausted my system. The database is tiny, after a mongodump, all files together weight 248KB. After some hours uptime it happens that the ...
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67 views

How to interpret Mongo MMS Stats?

The following image contains all of the charts from the Status tab in MMS. How does a noob looking at these charts navigate these waters, so to speak? The mongo box is a standalone installation ...
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1answer
55 views

Expand a date range in mongodb

I have a document structure like { "startDate": ISODate("2015-01-01T00:00:00Z"), "endDate" : ISODate("2015-01-10T00:00:00Z"), "foo" : "bar" } Is it possible to expand the date range like ...
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2answers
285 views

How MongoDB allocate new data block when data block is full

I am using MongoDB in my project. And I have some questions about how Mongo storage allocated. For example, I have 16MB full data block, and I want to add new document into this data block. - How ...
2
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1answer
188 views

MongoDB : How to estimate max number of connections supported?

We have a sharded cluster with 2 replica sets. Each replica set is a 3 member cluster with one primary and 2 secondaries. Each instance is a r3.large (aws-ec2) instance with 15G ram. mongos's are in ...
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1answer
568 views

MongoDB document size for collection - impact on RAM and query performance

I have been advised on stackoverflow to ask this question on dba.stackexchange instead - We are using MongoDB version 3.0 with WiredTiger storage. As newbies to MongoDB, we may have designed our ...
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1answer
472 views

Query MongoDB collection and find rows from 7 days ago

I have a MongoDB collection called messages and this is an example document for that collection: { "_id": { "$oid": "551943eee4c6acf40fe5a0f2" }, "sender_id": { "$oid": "...
0
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1answer
107 views

Size of data in secondary exceeded primary after its initial resync from primary in MongoDB

I step down the primary node, deleted its data and performed the initial resync from new primary. But when i checked the size of data after the completion of initial resync, I found that the size of ...
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2answers
6k views

check storage engine from shell

I'm upgrading to 3.0 and ran into some issues with the upgrade. Specifically, I got an error when trying to start up mongod via ssh, it tried to use the default dbpath instead of the one i specified ...
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74 views

Replica Set In Mongo Are All Primary

So I saw a thread on here for when all the replica sets are Primary. The fix was to do rs.Add(hostportStr) on the master server before you do rs.initiate() on the server you want to become a Secondary....