Error while installing cassandra

Question

I am trying to install apache cassandra on ubuntu 16.04 LTS following instructions here -> http://docs.datastax.com/en/cassandra/3.x/cassandra/install/installDeb.html.

However I am getting the following error while running sudo apt-get install datastax-ddc command:

Reading package lists... Done Building dependency tree  
Reading state information... Done Some packages could not be
installed. This may mean that you have requested an impossible
situation or if you are using the unstable distribution that
some required packages have not yet been created or been moved
out of Incoming. The following information may help to resolve
the situation:

The following packages have unmet dependencies:
  datastax-ddc :  Depends: python-support (>= 0.90.0) but it is not
                           installable  
                  Recommends: ntp but it is not going to be installed or  
                              time-daemon
                  Recommends: datastax-ddc-tools but it is not going to
                              be installed  E: Unable to correct problems,
                              you have held broken packages.

Is the datastax-ddc broken or something is wrong with my python?

Answer 1

For now, you may run the following steps:

1) Download the deb package from repository

apt-get download cassandra

2) Install the deb file, ignoring the dependencies

sudo dpkg --force-depends -i cassandra_3.5_all.deb

Obviously, you should make sure that all the other dependencies are satisfied. The python-support is already included in a default server installation, so no worries, however, python itself may not yet be installed on your system, so you should run the following BEFORE the dpkg -i ...:

sudo apt-get install python

To see the Depends: ... of the .deb before you try to install it, you may use the -I option as in:

dpkg -I cassandra_3.5_all.deb

In case of Cassandra 3.5, I see the following:

Depends: openjdk-8-jre-headless | java8-runtime, adduser, python (>= 2.7), python-support (>= 0.90.0)

So you could first run the following to make sure all dependencies are indeed satisfied:

sudo apt-get install adduser python oracle-java8-installer

or if you want to use the OpenJDK (NOT TESTED):

sudo apt-get install adduser python default-jre

Answer 2

The shorter version of the answer: ubuntu comes python 2 and python 3 installed but not the python-support which is now maintained by ajenti. So to have cassandra installed properly (as normal procedure described in the datastax doc)

https://askubuntu.com/questions/766169/why-no-more-python-support-in-16-04

curl https://raw.githubusercontent.com/ajenti/ajenti/master/scripts/install.sh > install.sh && sudo bash install.sh wget http://launchpadlibrarian.net/109052632/python-support_1.0.15_all.deb sudo dpkg -i python-support_1.0.15_all.deb