kolab gives error durring installation guide

Question

I am trying to install kolab onto my ubuntu 16.04 but with the guide found here
but i get an error on the step of doing the apt-get update thinking it is nothing major but as i went on to try the following command to install kolab that also gives an error

here are the two in order:

root@pe-fw:~# apt-get update
Get:1 http://security.ubuntu.com/ubuntu xenial-security InRelease [107 kB]
Hit:2 http://nl.archive.ubuntu.com/ubuntu xenial InRelease
Hit:3 http://nl.archive.ubuntu.com/ubuntu xenial-updates InRelease
Hit:4 http://nl.archive.ubuntu.com/ubuntu xenial-backports InRelease
Ign:5 http://obs.kolabsys.com/repositories/Kolab:/16/Ubuntu_16.04 ./ InRelease
Get:6 http://obs.kolabsys.com/repositories/Kolab:/16/Ubuntu_16.04 ./ Release [993 B]
Get:7 http://obs.kolabsys.com/repositories/Kolab:/16/Ubuntu_16.04 ./ Release.gpg [827 B]
Ign:8 http://mirror.jmu.edu/pub/mariadb/repo/10.1/ubuntu xenial InRelease
Ign:9 http://mirror.jmu.edu/pub/mariadb/repo/10.1/ubuntu xenial Release
Ign:10 http://mirror.jmu.edu/pub/mariadb/repo/10.1/ubuntu xenial/main Sources
Ign:11 http://mirror.jmu.edu/pub/mariadb/repo/10.1/ubuntu xenial/main ppc64el Packages
Ign:12 http://mirror.jmu.edu/pub/mariadb/repo/10.1/ubuntu xenial/main amd64 Packages
Ign:13 http://mirror.jmu.edu/pub/mariadb/repo/10.1/ubuntu xenial/main i386 Packages
Ign:14 http://mirror.jmu.edu/pub/mariadb/repo/10.1/ubuntu xenial/main all Packages
Ign:15 http://mirror.jmu.edu/pub/mariadb/repo/10.1/ubuntu xenial/main Translation-en_US
Ign:7 http://obs.kolabsys.com/repositories/Kolab:/16/Ubuntu_16.04 ./ Release.gpg
Hit:16 http://obs.kolabsys.com/repositories/Kolab:/16/Ubuntu_16.04 ./ Sources
Hit:17 http://obs.kolabsys.com/repositories/Kolab:/16/Ubuntu_16.04 ./ Packages
Ign:18 http://mirror.jmu.edu/pub/mariadb/repo/10.1/ubuntu xenial/main Translation-en
Ign:10 http://mirror.jmu.edu/pub/mariadb/repo/10.1/ubuntu xenial/main Sources
Ign:11 http://mirror.jmu.edu/pub/mariadb/repo/10.1/ubuntu xenial/main ppc64el Packages
Ign:12 http://mirror.jmu.edu/pub/mariadb/repo/10.1/ubuntu xenial/main amd64 Packages
Ign:13 http://mirror.jmu.edu/pub/mariadb/repo/10.1/ubuntu xenial/main i386 Packages
Ign:14 http://mirror.jmu.edu/pub/mariadb/repo/10.1/ubuntu xenial/main all Packages
Ign:15 http://mirror.jmu.edu/pub/mariadb/repo/10.1/ubuntu xenial/main Translation-en_US
Ign:18 http://mirror.jmu.edu/pub/mariadb/repo/10.1/ubuntu xenial/main Translation-en
Ign:10 http://mirror.jmu.edu/pub/mariadb/repo/10.1/ubuntu xenial/main Sources
Ign:11 http://mirror.jmu.edu/pub/mariadb/repo/10.1/ubuntu xenial/main ppc64el Packages
Ign:12 http://mirror.jmu.edu/pub/mariadb/repo/10.1/ubuntu xenial/main amd64 Packages
Ign:13 http://mirror.jmu.edu/pub/mariadb/repo/10.1/ubuntu xenial/main i386 Packages
Ign:14 http://mirror.jmu.edu/pub/mariadb/repo/10.1/ubuntu xenial/main all Packages
Ign:15 http://mirror.jmu.edu/pub/mariadb/repo/10.1/ubuntu xenial/main Translation-en_US
Ign:18 http://mirror.jmu.edu/pub/mariadb/repo/10.1/ubuntu xenial/main Translation-en
Ign:10 http://mirror.jmu.edu/pub/mariadb/repo/10.1/ubuntu xenial/main Sources
Ign:11 http://mirror.jmu.edu/pub/mariadb/repo/10.1/ubuntu xenial/main ppc64el Packages
Ign:12 http://mirror.jmu.edu/pub/mariadb/repo/10.1/ubuntu xenial/main amd64 Packages
Ign:13 http://mirror.jmu.edu/pub/mariadb/repo/10.1/ubuntu xenial/main i386 Packages
Ign:14 http://mirror.jmu.edu/pub/mariadb/repo/10.1/ubuntu xenial/main all Packages
Ign:15 http://mirror.jmu.edu/pub/mariadb/repo/10.1/ubuntu xenial/main Translation-en_US
Ign:18 http://mirror.jmu.edu/pub/mariadb/repo/10.1/ubuntu xenial/main Translation-en
Ign:10 http://mirror.jmu.edu/pub/mariadb/repo/10.1/ubuntu xenial/main Sources
Ign:11 http://mirror.jmu.edu/pub/mariadb/repo/10.1/ubuntu xenial/main ppc64el Packages
Ign:12 http://mirror.jmu.edu/pub/mariadb/repo/10.1/ubuntu xenial/main amd64 Packages
Ign:13 http://mirror.jmu.edu/pub/mariadb/repo/10.1/ubuntu xenial/main i386 Packages
Ign:14 http://mirror.jmu.edu/pub/mariadb/repo/10.1/ubuntu xenial/main all Packages
Ign:15 http://mirror.jmu.edu/pub/mariadb/repo/10.1/ubuntu xenial/main Translation-en_US
Ign:18 http://mirror.jmu.edu/pub/mariadb/repo/10.1/ubuntu xenial/main Translation-en
Err:10 http://mirror.jmu.edu/pub/mariadb/repo/10.1/ubuntu xenial/main Sources
  404  Not Found
Ign:11 http://mirror.jmu.edu/pub/mariadb/repo/10.1/ubuntu xenial/main ppc64el Packages
Ign:12 http://mirror.jmu.edu/pub/mariadb/repo/10.1/ubuntu xenial/main amd64 Packages
Ign:13 http://mirror.jmu.edu/pub/mariadb/repo/10.1/ubuntu xenial/main i386 Packages
Ign:14 http://mirror.jmu.edu/pub/mariadb/repo/10.1/ubuntu xenial/main all Packages
Ign:15 http://mirror.jmu.edu/pub/mariadb/repo/10.1/ubuntu xenial/main Translation-en_US
Ign:18 http://mirror.jmu.edu/pub/mariadb/repo/10.1/ubuntu xenial/main Translation-en
Fetched 109 kB in 4s (23.9 kB/s)
Reading package lists... Done
W: The repository 'http://mirror.jmu.edu/pub/mariadb/repo/10.1/ubuntu xenial Release' does not have a Release file.
N: Data from such a repository can't be authenticated and is therefore potentially dangerous to use.
N: See apt-secure(8) manpage for repository creation and user configuration details.
W: GPG error: http://obs.kolabsys.com/repositories/Kolab:/16/Ubuntu_16.04 ./ Release: The following signatures couldn't be verified because the public key is not available: NO_PUBKEY A01D0CA80038D0DB
W: The repository 'http://obs.kolabsys.com/repositories/Kolab:/16/Ubuntu_16.04 ./ Release' is not signed.
N: Data from such a repository can't be authenticated and is therefore potentially dangerous to use.
N: See apt-secure(8) manpage for repository creation and user configuration details.
E: Failed to fetch http://mirror.jmu.edu/pub/mariadb/repo/10.1/ubuntu/dists/xenial/main/source/Sources  404  Not Found
E: Some index files failed to download. They have been ignored, or old ones used instead.
root@pe-fw:~# apt-get install kolab
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:
 kolab : Depends: kolab-imap but it is not going to be installed
         Depends: kolab-webclient but it is not going to be installed
         Depends: kolab-webadmin but it is not going to be installed
E: Unable to correct problems, you have held broken packages.

Answer 1

You have two separate problems with apt here: Both the repository for mariadb and kolab are broken in your configuration. To install MariaDB 10, you could follow a different guide like this one where you would have to do only this block

sudo apt-get install software-properties-common
sudo apt-key adv --recv-keys --keyserver hkp://keyserver.ubuntu.com:80 0xF1656F24C74CD1D8
sudo add-apt-repository 'deb [arch=amd64,i386,ppc64el] http://ftp.utexas.edu/mariadb/repo/10.1/ubuntu xenial main

You see, it is very similar to the one in your guide.

The error from the kolab repo is caused by the developers who changed their release key. More about this can be found in this ticket. It can be fixed with this command:

wget -q -O- https://obs.kolabsys.com/repositories/Kolab:/16/Ubuntu_16.04/Release.key | sudo apt-key add -