root@danielss89:/# apt-get install proftpd
Reading package lists... Done
Building dependency tree... Done
Suggested packages:
  proftpd-doc
The following NEW packages will be installed:
  proftpd
0 upgraded, 1 newly installed, 0 to remove and 46 not upgraded.
Need to get 0B/847kB of archives.
After unpacking 2720kB of additional disk space will be used.
Preconfiguring packages ...
Selecting previously deselected package proftpd.
(Reading database ... 28718 files and directories currently installed.)
Unpacking proftpd (from .../proftpd_1.3.0-19_amd64.deb) ...
Setting up proftpd (1.3.0-19) ...
Adding system user `proftpd' (UID 110) ...
Adding new user `proftpd' (UID 110) with group `nogroup' ...
Not creating home directory `/var/run/proftpd'.
Starting ftp server: proftpd - IPv4 getaddrinfo 'danielss89' error: Name or service not known
 - warning: unable to determine IP address of 'danielss89'
 - error: no valid servers configured
 - Fatal: error processing configuration file '/etc/proftpd/proftpd.conf'
 failed!
invoke-rc.d: initscript proftpd, action "start" failed.
dpkg: error processing proftpd (--configure):
 subprocess post-installation script returned error exit status 1
Errors were encountered while processing:
 proftpd
E: Sub-process /usr/bin/dpkg returned an error code (1)