Linux - NetworkingThis forum is for any issue related to networks or networking.
Routing, network cards, OSI, etc. Anything is fair game.
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Hello, nmap on Linux CentOS always report "Host seems down." Please which commands should i do to discover cause?
No idea, because you *STILL* provide next to no useful information when asking a question, despite being asked to repeatedly. You don't say what version/distro of Linux, what environment this is running in, etc.
There could be a thousand different things, depending on the environment, like firewalls, routers/switches, WAN interfaces, etc., that you've not said anything about. Since you can ping it, then (as the message TELLS YOU), the scan is being blocked. Whether that's by the remote server, firewall, selinux, iptables, router/switch we can't tell you. Ask your system administrator and your network administrator...they will be able to help.
You can read the man pages/docs on nmap. It is different by default, ping is ICMP, and nmap ping sends a syn package: try using the -PE, -PM, -PP flags to make it do an ICMP ping. Are you running this as root?
yes, if provided info. is not enough, let me know which additional commands i should execute.
Again, you are missing the point. YOU need to provide the missing information. You STILL aren't answering the questions you were just asked, and you were handed something to try. Your response was to ask for yet MORE commands.
Ofcourse, i already tried -Pn but it says host is down while im sure it is up (can see ianfette.org webpage from my home computer), but from remote linux server it says down:
Quote:
# nmap ianfette.org -Pn -vv
Starting Nmap 5.51 ( http://nmap.org ) at 2016-07-19 11:38 EDT
Initiating ARP Ping Scan at 11:38
Scanning ianfette.org (173.201.140.128) [1 port]
Completed ARP Ping Scan at 11:38, 0.43s elapsed (1 total hosts)
Nmap scan report for ianfette.org (173.201.140.128) [host down]
Read data files from: /usr/share/nmap
Nmap done: 1 IP address (0 hosts up) scanned in 0.51 seconds
Raw packets sent: 2 (56B) | Rcvd: 0 (0B)
Ofcourse, i already tried -Pn but it says host is down while im sure it is up (can see ianfette.org webpage from my home computer), but from remote linux server it says down:
Please idea why down and how to fix? Thank you
Yes, you were spoon-fed an answer in post #2...did you not read or understand it?
You know where it said to "try -Pn" ?
Just a wild guess.
Good luck...I gave him the flags for nmap to use ICMP, and he's still asking...have also asked him for information, which is STILL missing. See any of the OP's other threads where such behavior is exhibited.
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