On 6/25/21 4:02 PM, Ed Greshko wrote:
On 24/06/2021 01:58, Gordon Messmer wrote:
> On 6/22/21 11:54 PM, Ed Greshko wrote:
>> [root@meimei ~]# nmap -sS -6 -p 2049 2001:b030:112f:2::53
>> Starting Nmap 7.80 (
https://nmap.org ) at 2021-06-23 14:47 CST
>> Nmap scan report for 2001:b030:112f:2::53
>> Host is up (0.00018s latency).
>>
>> PORT STATE SERVICE
>> 2049/tcp closed nfs
>>
>> Means the firewall is not blocking the port but no service is
>> listening on that port
>
>
> That's not entirely accurate. If the firewall action is REJECT rather
> than DROP, you'll see the same output from nmap. "closed" can mean
> either that the port is not open, or that the firewall is blocking
> access with a REJECT action.
OK, good to know, thanks. I don't think I've encountered that which may
explain my ignorance.
It's very rare. In almost all cases, DROP is the default. So the
"closed" result can be assumed to mean what you said it means.