Newer versions of netcat support both IPv4 and IPv6 and (for example) on Ubunutu 16.04 there is only on netcat package. This newer version of netcat does not have the "-4" and "-6" options anymore. Therefore the test in dashman/lib/dashman_functions.sh lines 164 and following fails, even if netcat is properly installed. It also suggest to run apt-get install netcat6 which does not work anymore as there is no netcat6 package.
Newer versions of netcat support both IPv4 and IPv6 and (for example) on Ubunutu 16.04 there is only on netcat package. This newer version of netcat does not have the "-4" and "-6" options anymore. Therefore the test in dashman/lib/dashman_functions.sh lines 164 and following fails, even if netcat is properly installed. It also suggest to run
apt-get install netcat6which does not work anymore as there is no netcat6 package.