mongo - couldn't connect to server 127.0.0.1:2

问题:

I am coming from riak and redis where I never had an issue with this services starting, or to interact.

This is a pervasive problem with mongo and am rather clueless. Restarting does not help.I am new to mongo.

mongo
MongoDB shell version: 2.2.1
connecting to: test
Fri Nov  9 16:44:06 Error: couldn't connect to server 127.0.0.1:27017 src/mongo/shell/mongo.js:91
exception: connect failed

This is what I see in the logs.

 now open)
Fri Nov  9 16:44:34 [conn47] end connection 10.29.16.208:5306 (1 connection now open)
Fri Nov  9 16:45:04 [initandlisten] connection accepted from 10.29.16.208:5307 #48 (2 connections now open)
Fri Nov  9 16:45:04 [conn48] end connection 10.29.16.208:5307 (1 connection now open)
Fri Nov  9 16:45:04 [initandlisten] connection accepted from 10.29.16.208:5308 #49 (2 connections now open)
Fri Nov  9 16:45:04 [conn49] end connection 10.29.16.208:5308 (1 connection now open)
Fri Nov  9 16:45:34 [initandlisten] connection accepted from 10.29.16.208:5316 #50 (2 connections now open)
Fri Nov  9 16:45:34 [conn50] end connection 10.29.16.208:5316 (1 connection now open)
Fri Nov  9 16:45:34 [initandlisten] connection accepted from 10.29.16.208:5317 #51 (2 connections now open)
Fri Nov  9 16:45:34 [conn51] end connection 10.29.16.208:5317 (1 connection now open)
Fri Nov  9 16:46:04 [initandlisten] connection accepted from 10.29.16.208:5320 #52 (2 connections now open)
Fri Nov  9 16:46:04 [conn52] end connection 10.29.16.208:5320 (1 connection now open)
Fri Nov  9 16:46:04 [initandlisten] connection accepted from 10.29.16.208:5321 #53 (2 connections now open)
Fri Nov  9 16:46:04 [conn53] end connection 10.29.16.208:5321 (1 conn

回答1:

This error is what you would see if the mongo shell was not able to talk to the mongod server.

This could be because the address was wrong (host or IP) or that it was not running. One thing to note is the log trace provided does not cover the "Fri Nov 9 16:44:06" of your mongo timestamp.

Can you:

1. Provide the command line arguments (if any) used to start your mongod process
2. Provide the log file activity from the mongod startup as well as logs during the mongo shell startup attempt?
3. Confirm that your mongod process is being started on the same machine as the mongo shell?

回答2:

Normally this caused because you didn't start mongod process before you try starting mongo shell.

Start mongod server

mongod

Open another terminal window

Start mongo shell

mongo

回答3:

Resolved.

This problem could be solved by the below mentioned 4 steps

1) Remove .lock file

sudo rm /var/lib/mongodb/mongod.lock 

2) repair the mongodb

mongod –repair

3) start the mongod server

sudo service mongod start 

4) start the mongo client

mongo

For more details take a look at http://shakthydoss.com/error-couldnt-connect-to-server-127-0-0-127017-srcmongoshellmongo-js-exception-connect-failed/

http://shakthydoss.com/technical/error-couldnt-connect-to-server-127-0-0-127017-srcmongoshellmongo-js-exception-connect-failed/

回答4:

This method only works if you want to repair your data files without preserving the original files

To find where you dbpath resides- vim /etc/mongodb.conf

check for option dbpath=

(I have dbpath=/var/lib/mongodb)

Default: /data/db/

Typical locations include: /srv/mongodb, /var/lib/mongodb or /opt/mongodb .

Replace the /var/lib/mongodb with your dbpath

sudo rm /var/lib/mongodb/mongod.lock
sudo mongod --dbpath /var/lib/mongodb/ --repair
sudo mongod --dbpath /var/lib/mongodb/ --journal

(Make sure that you leave you terminal running in which you have run above lines, dont press 'Ctrl+c' or quit it.) Type the command to start mongo now in another window.

Hope this works for you ! for those who want to repair your data files while preserving the original files mongo recover

回答5:

In my case:

First I open config file

sudo vi /etc/mongodb.conf

Comment IP and Port like this

#bind_ip = 127.0.0.1
#port = 27017

Then restart mongodb

sudo service mongodb restart
sudo service mongod restart

Finally, it's work :D

finn@Finn ~ $ mongo
MongoDB shell version: 2.4.9
connecting to: test
> exit

回答6:

Make sure that your mongo is running. I fixed this problem by trying to repair the mongodb, there I found that the directory required for the db to run was not created. It shows this error

Type: mongod, it will show the error

exception in initAndListen: 29 Data directory /data/db not found., terminating

Error happen because dbpath /data/db/ (default config) does not exist. You need to create data folder and set permission for it.

Then I create a folder on my system by the command

sudo mkdir -p /data/db/ and sudo chown id -u /data/db

then I run the mongo again and it worked.

回答7:

A little to late with the answer but I've encountered the same issue

Following are the steps which helped me.

1. Go to C:\
2. Create "data" folder
3. In "data" create "db" folder
4. open terminal (CMD) -> go to EX:"c:\MongoDB\Server\3.4\bin"
5. type in mongod => this will start mongo server (leave it opened)

Run using a GUI, EX "robomongo"

Or

open new terminal (CMD) -> go to EX:"c:\MongoDB\Server\3.4\bin" type in "mongo" command

回答8:

If all the above solution does not work: go to service (start>search>services) and start mongodb service. Then, in a cmd prompt, after going to bin, type :/>mongo

回答9:

To connect with mongo we have to first start 'mongod' services. following output you can see :

$ mongod
2017-03-05T00:31:39.055+0530 I CONTROL  [initandlisten] MongoDB starting : pid=1481 port=27017 dbpath=/data/db 64-bit host=Prabhu-Nandans-Mac.local
2017-03-05T00:31:39.056+0530 I CONTROL  [initandlisten] db version v3.4.2
2017-03-05T00:31:39.056+0530 I CONTROL  [initandlisten] git version: 3f76e40c105fc223b3e5aac3e20dcd026b83b38b
2017-03-05T00:31:39.056+0530 I CONTROL  [initandlisten] OpenSSL version: OpenSSL 1.0.2k  26 Jan 2017
2017-03-05T00:31:39.056+0530 I CONTROL  [initandlisten] allocator: system
2017-03-05T00:31:39.056+0530 I CONTROL  [initandlisten] modules: none
2017-03-05T00:31:39.056+0530 I CONTROL  [initandlisten] build environment:
2017-03-05T00:31:39.056+0530 I CONTROL  [initandlisten]     distarch: x86_64
2017-03-05T00:31:39.056+0530 I CONTROL  [initandlisten]     target_arch: x86_64
2017-03-05T00:31:39.056+0530 I CONTROL  [initandlisten] options: {}
2017-03-05T00:31:39.056+0530 W -        [initandlisten] Detected unclean shutdown - /data/db/mongod.lock is not empty.
2017-03-05T00:31:39.057+0530 I -        [initandlisten] Detected data files in /data/db created by the 'wiredTiger' storage engine, so setting the active storage engine to 'wiredTiger'.
2017-03-05T00:31:39.057+0530 W STORAGE  [initandlisten] Recovering data from the last clean checkpoint.
2017-03-05T00:31:39.057+0530 I STORAGE  [initandlisten] wiredtiger_open config: create,cache_size=3584M,session_max=20000,eviction=(threads_max=4),config_base=false,statistics=(fast),log=(enabled=true,archive=true,path=journal,compressor=snappy),file_manager=(close_idle_time=100000),checkpoint=(wait=60,log_size=2GB),statistics_log=(wait=0),
2017-03-05T00:31:39.620+0530 I CONTROL  [initandlisten] 
2017-03-05T00:31:39.620+0530 I CONTROL  [initandlisten] ** WARNING: Access control is not enabled for the database.
2017-03-05T00:31:39.620+0530 I CONTROL  [initandlisten] **          Read and write access to data and configuration is unrestricted.
2017-03-05T00:31:39.620+0530 I CONTROL  [initandlisten] 
2017-03-05T00:31:39.620+0530 I CONTROL  [initandlisten] 
2017-03-05T00:31:39.620+0530 I CONTROL  [initandlisten] ** WARNING: soft rlimits too low. Number of files is 256, should be at least 1000
2017-03-05T00:31:39.643+0530 I FTDC     [initandlisten] Initializing full-time diagnostic data capture with directory '/data/db/diagnostic.data'
2017-03-05T00:31:39.643+0530 I NETWORK  [thread1] waiting for connections on port 27017
2017-03-05T00:31:40.008+0530 I FTDC     [ftdc] Unclean full-time diagnostic data capture shutdown detected, found interim file, some metrics may have been lost. OK
2017-03-05T00:32:03.832+0530 I NETWORK  [thread1] connection accepted from 127.0.0.1:49806 #1 (1 connection now open)
2017-03-05T00:32:03.833+0530 I NETWORK  [conn1] received client metadata from 127.0.0.1:49806 conn1: { application: { name: "MongoDB Shell" }, driver: { name: "MongoDB Internal Client", version: "3.4.2" }, os: { type: "Darwin", name: "Mac OS X", architecture: "x86_64", version: "16.4.0" } }
2017-03-05T00:32:08.376+0530 I -        [conn1] end connection 127.0.0.1:49806 (1 connection now open)

After that open another terminal and just type 'mongo'.

Following is output you can see :

$ mongo
MongoDB shell version v3.4.2
connecting to: mongodb://127.0.0.1:27017
MongoDB server version: 3.4.2

Your issue solved :)

回答10:

Another solution that resolved this same error for me, though this one might only be if you are accessing mongo (locally) via a SSH connection via a virtual machine (at least that's my setup), and may be a linux specific environment variable issue:

export LC_ALL=C

Also, I have had more success running mongo as a daemon service then with sudo service start, my understanding is this uses command line arguments rather then the config file so it likely is an issue with my config file:

mongod --fork --logpath /var/log/mongodb.log --auth --port 27017 --dbpath /var/lib/mongodb/admin

回答11:

Create the folder C:data/db if it doesn't already exist on your computer. Turns out MongoDB requires the existence of this folder structure 'data/db' to run. I hope this helps someone.

回答12:

The cause by me was the space - run this in the console:

df -h

or more specifically:

du -hs /var/lib/mongodb/ 

to check he disk usage. If it's ~ 99% - just clean up some space and try again!

回答13:

First, go to c:\mongodb\bin> to turn on mongoDB, if you see in console that mongo is listening in port 27017, it is OK If not, close console and create folder c:\data\db and start mongod again

回答14:

You can try with following command:

sudo service mongod start

回答15:

This was happening with me today and I resolved it in following way.

Machine: I'm using Windows 10 machine and downloaded the latest MongoDB - Community edition.

So, the problem was, I did not have C:\data\db created.

Without creating C:\data\db, I opened CMD terminal and started the database using mongod command at terminal

C:\YourInstallationPath\bin>mongod

And when I fired mongo command then I was getting the problem.

Twist, I created the necessary folders but still was getting the problem. And this is because mongo server was already running. To fix it, I fired up mongod command again, and it automatically referenced to C:\data\db.

Other users have suggested to add C:\data\db but did not talk about executing mongod again, which exactly solved my problem.

回答16:

I also have the same problem then I got fixed by these two lines of code. Hope, it helps

systemctl start mongod
systemctl enable mongod

回答17:

@shakthydoss answer worked fine once, but after the second issue the .lock wasn't there, I just created a blank one, and it worked fine. So check if yours ain't there.

If you are using the command line:

cd /var/lib/mongodb

ls

"ls" will list all the files in the folder, if the mongod.lock isn't there, then:

sudo touch mongod.lock

Finally run command.

mongod –-repair

sudo service mongod start 

Mongo service should be working fine.

回答18:

I am a windows user and I installed MongoDB in November 2018 and I didn't wanted to setup data/db directories. But after few days, when I open, got an error message:

MongoDB shell version v4.0.4
connecting to: mongodb://127.0.0.1:27017
2018-12-05T20:42:40.108+0530 E QUERY    [js] Error: couldn't connect to server 127.0.0.1:27017, connection attempt failed: SocketException: Error connecting to 127.0.0.1:27017 :: caused by :: No connection could be made because the target machine actively refused it. :
connect@src/mongo/shell/mongo.js:257:13
@(connect):1:6
exception: connect failed

Then I tried to fix using all of above answers and didn't worked. When I tried to run mongod it said

MongoDB starting : pid=12220 port=27017 dbpath=C:\data\db\ 64-bit host=bla

I tried to change the db path(to program files) through file system and also using cmd but those didnot worked.

Solution that worked for me is:

Opened the Task Manager (ctrl + shift + esc) -> Services tab and there was a MongoDB row with the status stopped. Then I right clicked and clicked start and everything working perfectly :).

回答19:

Remove mongod.lock file. And run "mongod -repair". uninstall/reinstall mongod service fixed that problem for me.

Thanks.

回答20:

I had the same error when connecting to Mongo on AWS EC2 . This is what solved it https://serverfault.com/a/347159/62381 Remove the bind_ip from the config file

回答21:

This work me:-

In Mongo 3.2 for window, you should start Mongodb service. So, run the Command Prompt as Administrator then net start MongoDB

回答22:

Finally I got this is in a simple way..

open terminal and go to the mongodb location. In my case it is

e:\mongodb\bin> 

and type the following command and press enter..

mongod --config e:\mongodb\mongo.config

Open another terminal and start the mongodb using

mongo.exe

Thats it.. you can use mongo

回答23:

This is an old question, but, as a newbie I figured I'd add that (using Webstorm) you need to click on Mongo Explorer (tab on far right hand side of your window). From there:

-Click settings. -Click browse button (looks like a button with "..." on it). -Go to Program Files > MongoDB > Server > 3.4 > bin > mongo.exe (your version maybe different than 3.4) -After that, click the green plus sign on the right. A window will open -Enter a name in "Label" slot. -Click apply.

You should now be connected. Entering "mongod" in the terminal isn't enough. You have to do the above steps also.

My apologies in advance to those of you who aren't using Webstorm! Not sure about the steps using other IDE's.

回答24:

if u install by brew (on osx) first run sudo mkdir /data/db start mondoDB Daemon by typing mongod (leave it open) and then run mongo by typing mongo in new terminal tab

回答25:

Simply create a folder named "data" in C drive and inside data folder create another folder named "db". Then execute mongod.exe :)

回答26:

First, you have to start mongod server then after in another terminal you have to start mongo shell.

For starting, mongo server

1. If you path is Default path (data/db) simple fired mongod in terminal

2. If your path is not data/db then you command like as follow: mongod --dbpath 'here your path comes' .

For starting mongo shell, Simply fired mongo in another terminal

If you get this waiting for connections on port 27017, then your mongo successfully started.

Hope you can get my point

回答27:

if all the solution above doesn't work out perhaps then this might be one to help. Somewhere down the line you may have made connection to your local mongodb database via vagrant boxes.

1. vagrant up and then ssh into your vagrant machine in which you've made connection with mongodb (vagrant ssh vagrant_box_name)
2. comment out the bind_ip line from /etc/mongod.conf using # (sudo nano /etc/mongod.conf )
3. restart your mongodb daemon service (sudo service mongod restart) voila...

回答28:

i had same problem, i have deleted E:\Mongo Data Files\db\mongod.lock file, so it started working. the problem is due to improper shutdown of server. so lock file is not clean.

回答29:

Steps to solve this issue on Windows OS:

1. Delete mongod.lock file from C:\Program Files\MongoDB\Server\4.0\data
2. Click on mongod in C:\Program Files\MongoDB\Server\4.0\bin
3. Click on mongo in C:\Program Files\MongoDB\Server\4.0\bin to start the mongodb shell