Day: March 6, 2015

Details about pg gem error: Can’t find the ‘libpq-fe.h header when doing bundle in Rails

If you are getting errors like:

installing pdf-reader 1.3.3
Gem::Ext::BuildError: ERROR: Failed to build gem native extension.

/home/vagrant/.rvm/rubies/ruby-2.2.0/bin/ruby -r ./siteconf20150306-5919-1rr483p.rb extconf.rb
checking for pg_config... yes
Using config values from /usr/bin/pg_config
You need to install postgresql-server-dev-X.Y for building a server-side extension or libpq-dev for building a client-side application.
You need to install postgresql-server-dev-X.Y for building a server-side extension or libpq-dev for building a client-side application.
checking for libpq-fe.h... no
Can't find the 'libpq-fe.h header
*** extconf.rb failed ***
Could not create Makefile due to some reason, probably lack of necessary
libraries and/or headers. Check the mkmf.log file for more details. You may
need configuration options.

when trying to install pg gem,
you are just missing some dependancy library related to libpq. Install the following package


$ sudo apt-get install libpq-dev

then do


$ gem install pg -v 'version-no'

then do


bundle install

How to reinstall mongodb in ubuntu linux

Before reinstalling mongodb, in your linux system check whats installed in the system

 $ sudo dpkg -l | grep mongo
 ii  mongodb-org                              2.6.3                                       amd64        MongoDB open source document-oriented database system (metapackage)
 ii  mongodb-org-mongos                       2.6.3                                       amd64        MongoDB sharded cluster query router
 ii  mongodb-org-server                       2.6.3                                       amd64        MongoDB database server
 ii  mongodb-org-shell                        2.6.3                                       amd64        MongoDB shell client
 ii  mongodb-org-tools                        2.6.3                                       amd64        MongoDB tools

Remove all
$ sudo apt-get remove mongodb*

Install mongodb again, check mongodb org

$ sudo apt-get install -y mongodb-org

For particular version

$ sudo apt-get install -y mongodb-org=2.6.5 mongodb-org-server=2.6.5 mongodb-org-shell=2.6.5 mongodb-org-mongos=2.6.5 mongodb-org-tools=2.6.5


check whats newly installed

$ sudo dpkg -l | grep mongo
 ii  mongodb-org                              2.6.8                                       amd64        MongoDB open source document-oriented database system (metapackage)
 ii  mongodb-org-mongos                       2.6.8                                       amd64        MongoDB sharded cluster query router
 ii  mongodb-org-server                       2.6.8                                       amd64        MongoDB database server
 ii  mongodb-org-shell                        2.6.8                                       amd64        MongoDB shell client
 ii  mongodb-org-tools                        2.6.8                                       amd64        MongoDB tools

check mongodb server status

$ sudo service mongod status

Start mongodb server

$ sudo service mongod start

Start mongo shell

$ mongo

check mongodb log file here

 $ tail -n 200 /var/log/mongodb/mongod.log