Could not connect to a primary node for replica set #<Moped::Cluster[<Moped::Node resolved_address="10.10.4.131:27017">]

Question

On my local Mac OSX, I want to run a rake task on a server which is within the my network. All the seeds to the remote mysql database work fine. But when I try to seed the mongodb data, I get the following error:

bundle exec rake db:seed RAILS_ENV=staging
rake aborted!
Moped::Errors::ConnectionFailure: Could not connect to a primary node for replica set 
#<Moped::Cluster:70258359778560 @seeds=[<Moped::Node resolved_address="10.10.4.131:27017">]>
/Users/donato/.rvm/gems/ruby-2.1.2@core/gems/moped-2.0.4/lib/moped/cluster.rb:254:in `with_primary'

I am able to deploy to that server using capistrano. So I know it is not a networking issue. I also already tried the solution here. I deleted mongod.lock and then ran service mongod restart, without luck. However in that question, he was trying to run it on localhost, whereas I want to run it on another computer but within my network. What can I do?

Answer 1

Ok, I resolved it. Apparently, mongodb by default does not allow remote connections. It will only be available on the local interface and therefore accessible only within the machine itself:

# netstat -tulpn | grep mongod
tcp        0      0 127.0.0.1:27017             0.0.0.0:*                   LISTEN      12963/mongod  

To solve this problem find out where your mongodb config file is:

# find / -type f -name mongod*
/etc/mongodb.conf

Then edit the file and add then add the private ip address of your machine (if the remote computer is in the same network as your local machine, otherwise you would have to add the public ip address as well):

bind_ip = 127.0.0.1,10.10.4.131

Then restart mongodb and check that it is listening on the private ip (in addition to the loopback interface):

service mongod restart
# netstat -tulpn | grep mongod
tcp        0      0 10.10.4.131:27017           0.0.0.0:*                   LISTEN      12963/mongod        
tcp        0      0 127.0.0.1:27017             0.0.0.0:*                   LISTEN      12963/mongod     

If you have a firewall, open the port up:

iptables -A INPUT -p tcp --dport 27017 -j ACCEPT

Then confirm from your local machine that you can now access that port remotely:

$ nc -z 10.10.4.131 27017
Connection to 10.10.4.131 port 27017 [tcp/*] succeeded!

And there you have it. Now we can seed the staging mongodb database from our local machine:

bundle exec rake db:seed RAILS_ENV=staging

Answer 2

This is just because you have not stopped mongodb correctly and mongod lock is created. just delete mongob lock.Follow this two steps

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

2.sudo service mongodb start