On Fri, 19 Sep 2014, Ulf Volmer wrote: > On 09/19/2014 03:58 PM, kqt4at5v at gmail.com wrote: >> On Fri, 19 Sep 2014, Reindl Harald wrote: >>> Am 19.09.2014 um 15:45 schrieb kqt4at5v at gmail.com: >>>> I am running CentOS 6.5. I know this is not a CentOS specific problem. >>>> Netstat shows several open ports and no pid. >>>> >>>> tcp 0 0 *:48720 *:* LISTEN - >>>> tcp 0 0 *:43422 >>>> *:* LISTEN - >>>> udp 0 0 *:50216 *:* >>> >>> alias netstat='/bin/netstat --numeric-hosts --numeric-ports --notrim >>> --programs -u -t' >>> /bin/netstat > >> This netstat show exactly the same. Lsof does not show these ports. > > This looks like these port are opened by kernel, not by a process, for > example like nfs. > How can I know for sure?