I have installed MongoDB 3.0.1 following the commands in Install MongoDB Community Edition on Ubuntu on my ubuntu 14.04 64 bit system and I installed Robomongo interface to use that.
When I try to connect MongoDB using Robomongo I get an error that authorization failed. I found Add support for SCRAM-SHA-1 authentication (MongoDB 3.0+) which explains that Robomongo 0.8.5 doesn't support MongoDB 3.0.X fully.
In response, I want to remove MongoDB 3.0.1 and install MongoDB 2.2.
I tried the following commands:
apt-get remove --purge mongodb
and also
apt-get autoremove --purge mongodb
In both cases I got the following error:
" Could not open lock file /var/lib/dpkg/lock - open (13: Permission denied) E: Unable to lock the administration directory (/var/lib/dpkg/), are you root?"
Any help would be appreciated.
sudo service mongod stop
sudo apt-get purge mongodb-org*
sudo rm -r /var/log/mongodb
sudo rm -r /var/lib/mongodb
this worked for me