Hi there On 22/08/17 11:44, tomas@tuxteam.de wrote: <Cut>
This raises the question why netstat does not show Rob's NFS ports. Does NFS change the port fast enough so that netstat and port scan differ ?A good question. I guess we need more details from the OP.
The hidden port lingers on for days. Until one restarts NFS. NFS then uses an other port which clearly shows in netstat, until it becomes hidden again. And the daily rkhunter [1] starts complaining about it.
[1] https://en.wikipedia.org/wiki/Rkhunter I think this may be a kernel bug. Regards, Rob