Solution:
Ubuntu switched to systemd as its service framework begining in 15.04 for all flavors, along Desktop and Server. The recommended exercise is to alter your upstart jobs to systemd jobs . You can further switch back to upstart in case you want, which is surely the quicker solve. I recommend you read the first some sections of the wiki article to weight the pros and cons.
Recommended Fix
Mention to the wiki article to transition your upstart scripts to systemd.
Quick Solve (for 15.04 only)
To abidingly switch back to upstart just run:
sudo apt-get install upstart-sysv
sudo update-initramfs -u
sudo reboot
I traced the issue for fail2ban was an error in the configuration file: /etc/fail2ban/jail.local
In the pam section, the port variable is listed twice
[pam-generic]
...
port = all
banaction = iptables-allports
port = anyport
In fact though this section is disabled (enabled = false) in my configuration, this reasons an error. I easily commented out this second definition
# port = anyport
I constructed this by running fail2ban manually:
sudo fail2ban-client start
Vivid now conducts systemd instead of upstart.
You can attempt: "sudo systemctl start " instead.
Introduction
This document compares Upstart and systemd for supporting in the transition to the latter.
Support status
First, it is significant to note that systemd is just fully supported in Ubuntu 15.04 and later releases. While systemd is available in previously releases through the Ubuntu repositories, there is a deemphasis of support for these releases as noted here. Therefore, it is advised to employ the default upstart on prior releases.
System Init Daemon
This has altered as part of the Ubuntu 15.04 devel cycle.
Ubuntu 15.04 (employing Systemd by default):
Systemd runs with PID 1 as /sbin/init.
Upstart runs with PID 1 as /sbin/upstart.
Previous versions (employing Upstart by default):
Upstart runs with PID 1 as /sbin/init.
Systemd runs with PID 1 as /lib/systemd/systemd.
Switching init systems
In case you are running Ubuntu vivid (15.04), you can simply switch between upstart and systemd at will because both packages are installed at current. As of March 9 2015, vivid was altered to exercise systemd by default, prior that upstart was the default.
Switch to upstart for a single boot
In grub, select "Advanced options for Ubuntu", where you will trace an "Ubuntu, with Linux ... (upstart)" entry. This will boot with init=/sbin/upstart.
In case you have upstart-sysv installed and thus boot with upstart by default, there will be an "Ubuntu, with Linux ... (systemd)" entry, which will boot with init=/lib/systemd/systemd.
Permanent switch back to upstart
Install the upstart-sysv package, which will remove ubuntu-standard and systemd-sysv (however must not remove anything else -- in case it does), and run sudo update-initramfs -u. Afterwards, grub's "Advanced options" menu will have a similar "Ubuntu, with Linux .(systemd)" entry where you can do an one-time boot with systemd.
In case you want to switch back to systemd, install the systemd-sysv and ubuntu-standard packages.
Presently you can switch to upstart, impart the developers of the package in question of the require to support systemd.
