Cannot create container for service xxx: invalid mode: /path/to/volume/

Problem

You are trying to use docker-compose to get some services up with docker but you see an error like the following:

Cannot create container for service xxx: invalid mode: /path/to/volume/

Solution

This is more than likely caused by a typo in your yml file, so go back and check carefully for any typos and correct them.

ERROR: Couldn’t connect to Docker daemon at http+docker://localunixsocket – is it running?

Problem

Using docker-compose up (or build), displays the following error message (even though the same command used to work previously):

ERROR: Couldn't connect to Docker daemon at http+docker://localunixsocket - is it running?

Solution

This is quite possible caused by permissions issue, as one of the folders files that docker is trying to use is owned by a different user/group from the one trying to use the docker-compose commands. Try to find the file/folder with the different permissions and change it to your user name and group, or use change the files by using something like:

chown -R me:me .

libv8 error in new rails installation

Problem

You are getting a libv8 installation error in a new rails 4.0 application in an older linux installation

An error occurred while installing libv8 (3.16.14.3), and Bundler cannot continue.
Make sure that `gem install libv8 -v '3.16.14.3'` succeeds before bundling.

Solution

This is causes by the latest gem version of the therubyracer dependency on the libv8.
You can get over it by specifying version 0.11.4 for the gem as in:

gem 'therubyracer', '~> 0.11.4', platforms: :ruby

and then running bundle install again.

Parent task translation missing: en, activerecord, errors, models, issue, attributes, parent_issue_id, not_a_valid_parent

Problem
You get the following error in redmine when trying to update a task that has a parent task.

Parent task translation missing: en, activerecord, errors, models, issue, attributes, parent_issue_id, not_a_valid_parent

Solution
It seems that for some reason when you add more than one subtask, the lft and rgt id numbers are not created correctly so you cannot update the subtasks.
If the numbers are overlapping (rgt for first subtask 2 and lft for second subtask 2), then there is a problem.
So in order to be able to solve that you will need to change the lft, rgt ids to have subsequent numbers as:
first subtask: lft -> 1 , rgt -> 2
second subtask: lft -> 3, rgt -> 4

undefined method `find_by_contents’ ,acts_as_ferret

Problem
When trying to use the acts_as_ferret plugin in a search page by using the find_by_contents method then the following error appears:

undefined method `find_by_contents'

Solution
It seems that the API of the plugin has changed, and the

find_by_contents

method should be replaced with the:

find_with_ferret

method

ERROR: While executing gem … (ArgumentError)

Problem
After a recent upgrade to a newer rails version the gem package manager seems to be broken. Everytime you try to use gem install gem_name, you get the following error:

ERROR:  While executing gem ... (Gem::GemNotFoundException)

Deleting the cached files as suggested in other posts results in the error:

ERROR:  While executing gem ... (ArgumentError)

Solution
As suggested here, you need to do:

gem install rubygems-update
update_rubygems

which should be updating the gem version to the latest one, ie 1.3.0