[CentOS] Centos 7 force reverse dns lookup for none registered addr

Thu Jan 12 12:58:38 UTC 2017
Steven Tardy <sjt5atra at gmail.com>

> On Jan 10, 2017, at 4:17 PM, Itschak Mugzach <imugzach at gmail.com> wrote:
> 
> after reviewing TCPDUMP

Did you `tcpdump` with the -nn option? If not than tcpdump was probably doing the reverse DNS lookup.