Commands tagged nmap (18)

  • Find all active ip's in a subnet

    nmap for windows and other platforms is available on developer's site: http://nmap.org/download.html nmap is robust tool with many options and has various output modes - is the best (imho) tool out there.. from nmap 5.21 man page: -oN/-oX/-oS/-oG : Output scan in normal, XML, s| Show Sample Output


    6
    nmap -v -sP 192.168.0.0/16 10.0.0.0/8
    anapsix · 2010-07-14 19:53:02 0
  • Using NMAP to check if a port is open or close

    Using NMAP to check to see if port 22(SSH) is open on servers and network devices. Show Sample Output


    6
    nmap -oG - -T4 -p22 -v 192.168.0.254 | grep ssh
    SeeFor · 2011-01-11 16:12:23 0
  • network interface and routing summary


    6
    nmap --iflist
    bandie91 · 2013-06-22 10:50:43 1
  • nmap get all active online ips from specific network

    scan whole specific network for active online ips Show Sample Output


    5
    nmap -n -sn 192.168.1.0/24 -oG - | awk '/Up$/{print $2}'
    aysadk · 2019-09-04 13:31:53 0
  • List of reverse DNS records for a subnet

    This command uses nmap to perform reverse DNS lookups on a subnet. It produces a list of IP addresses with the corresponding PTR record for a given subnet. You can enter the subnet in CDIR notation (i.e. /24 for a Class C)). You could add "--dns-servers x.x.x.x" after the "-sL" if you need the lookups to be performed on a specific DNS server. On some installations nmap needs sudo I believe. Also I hope awk is standard on most distros. Show Sample Output


    4
    nmap -R -sL 209.85.229.99/27 | awk '{if($3=="not")print"("$2") no PTR";else print$3" is "$2}' | grep '('
    netsaint · 2009-09-02 16:33:15 1
  • How many Linux and Windows devices are on your network?

    Shows how many Windows and Linux devices are on your network. May add support for others, but that's all that are on my network right now. Show Sample Output


    3
    sudo nmap -F -O 192.168.1.1-255 | grep "Running: " > /tmp/os; echo "$(cat /tmp/os | grep Linux | wc -l) Linux device(s)"; echo "$(cat /tmp/os | grep Windows | wc -l) Window(s) devices"
    matthewbauer · 2010-01-10 03:09:56 2
  • Scan Subnet for IP and MAC addresses


    3
    nmap -sP 192.168.1.0/24
    harpo · 2014-11-07 12:15:06 0
  • Ping all hosts on 192.168.1.0/24


    2
    nmap -sn 192.168.1.0/24
    pdxdoughnut · 2014-01-28 23:32:18 0
  • Ping all hosts on 192.168.1.0/24

    Will report back IP address's of all hosts that are UP. Show Sample Output


    2
    fping -ga 192.168.1.0/24 2> /dev/null
    netaxiz · 2014-01-31 19:19:19 0
  • Scan your LAN for unauthorized IPs

    populate the auth.hosts file with a list of IP addresses that are authorized to be in use and when you run this command it will return the addresses that are pingable and not in the authorized list. Can be combined with the "Command line Twitter" command to tweet unauthorized access. Show Sample Output


    1
    diff <(nmap -sP 192.168.1.0/24 | grep ^Host | sed 's/.appears to be up.//g' | sed 's/Host //g') auth.hosts | sed 's/[0-9][a-z,A-Z][0-9]$//' | sed 's/</UNAUTHORIZED IP -/g'
    bandit36 · 2009-03-12 05:28:08 3
  • nmap port scanning

    TCP Connect scanning for localhost and network 192.168.0.0/24 Show Sample Output


    1
    nmap -v -sT 192.168.0.0/24
    Dhinesh · 2011-11-19 07:06:52 0
  • checks if host /service is up on a host that doesn't respond to ping

    the command for the impatient sysadmin: simply checks every five secs, if a host or a specific service running on it is up. ideal for hosts that are configured not to respond on pings. Show Sample Output


    0
    while true; do clear; nmap ${hostname} -PN -p ${hostport}; sleep 5; done
    flokra · 2009-08-14 20:19:59 0
  • Nmap find open TCP/IP ports for a target that is blocking ping

    Change the IP address from 127.0.0.1 to the target machines ip address. Even if the target has ICMP (ping) blocked, it will show you what ports are open on the target. Very handy for situations where you know the target is up and online but wont respond to pings. Show Sample Output


    0
    nmap -sT -PN -vv <target ip>
    Richie086 · 2011-07-22 02:37:19 0
  • Check a port's state on a given host

    Check to see if a port is open or closed on a given host. Show Sample Output


    0
    checkport() { sudo nmap -sS -p $1 $2 }
    peterRepeater · 2011-12-13 11:46:15 1
  • Find resolvable hosts in subnet

    Nmap will list all IP's in the target specified, can specify subnet or range of IP addresses. It will attempt to resolve all IP's listed. No packets sent to target only generates DNS queries. Show Sample Output


    0
    nmap -sL 74.125.237.1/24
    the_wanderer · 2012-05-30 00:51:20 0
  • Using NMAP to check if a port is open or close


    0
    nmap -n 10.0.0.50 | grep udp | cut -d":"-f3>> test02
    h_kaur2 · 2015-11-13 13:28:35 0
  • Using NMAP to check if a port is open or close


    0
    nmap -n 10.0.0.50 | grep udp | cut -d":"-f3>>
    h_kaur2 · 2015-11-13 13:31:14 0
  • Display live hosts on the network

    Displays live hosts on the same network as the local machine with their hostnames and IP addresses. This command is IPv6 and multiple network adapter safe and does not rely on awk or sed, however it requires the "nmap" package installed. Might not work on OSX. Example alias for shell startup file: alias livehosts='nmap -sP "$(ip -4 -o route get 1 | cut -d " " -f 7)"/24 | grep report | cut -d " " -f 5-' Show Sample Output


    -2
    nmap -sP "$(ip -4 -o route get 1 | cut -d ' ' -f 7)"/24 | grep report | cut -d ' ' -f 5-
    lordtoran · 2019-02-01 03:52:02 0

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