Results 1 to 6 of 6

Thread: Nmap extremely slow on my laptop

  1. #1
    Join Date

    Nmap extremely slow on my laptop

    Hi all, I've got this big problem using nmap in my laptop, it runs extremely slow, a normal scan takes normaly more than 10/15 minutes, I'm experiencing this issue since the first time I installed nmap on Windows.
    I recently installed Kali, but this problem persist, I think that is because of the Wi-Fi card because if I try to run the same nmap scan inside a virtual machine it executes perfectly in less than 10 seconds.
    Here are my specs:

    Laptop: Acer Aspire E5-571G-71E7
    OS: Kali GNU/Linux Rolling 64-bit
    RAM: 8 GB DDR3
    CPU: Intel Core i7-4510U 2.0GHz
    Wi-Fi Card: Qualcomm Atheros QCA9565 / AR9565 Wireless Network Adapter

    Output running lspci -v:
    02:00.0 Network controller: Qualcomm Atheros QCA9565 / AR9565 Wireless Network Adapter (rev 01)
    	Subsystem: Foxconn International, Inc. QCA9565 / AR9565 Wireless Network Adapter
    	Flags: bus master, fast devsel, latency 0, IRQ 19
    	Memory at b3400000 (64-bit, non-prefetchable) [size=512K]
    	Expansion ROM at b3480000 [disabled] [size=64K]
    	Capabilities: [40] Power Management version 2
    	Capabilities: [50] MSI: Enable- Count=1/4 Maskable+ 64bit+
    	Capabilities: [70] Express Endpoint, MSI 00
    	Capabilities: [100] Advanced Error Reporting
    	Capabilities: [140] Virtual Channel
    	Capabilities: [160] Device Serial Number 00-00-00-00-00-00-00-00
    	Kernel driver in use: ath9k
    	Kernel modules: ath9k
    Output running iwconfig:
    eth0      no wireless extensions.
    wlan0     IEEE 802.11bgn  ESSID:"TeleTu_DC0B1A0C599E"  
              Mode:Managed  Frequency:2.462 GHz  Access Point: DC:0B:1A:0C:59:9E   
              Bit Rate=1 Mb/s   Tx-Power=15 dBm   
              Retry short limit:7   RTS thr:off   Fragment thr:off
              Encryption key:off
              Power Management:off
              Link Quality=48/70  Signal level=-62 dBm  
              Rx invalid nwid:0  Rx invalid crypt:0  Rx invalid frag:0
              Tx excessive retries:0  Invalid misc:16   Missed beacon:0
    lo        no wireless extensions.
    Output running route -n:
    Kernel IP routing table
    Destination     Gateway         Genmask         Flags Metric Ref    Use Iface         UG    600    0        0 wlan0   U     600    0        0 wlan0

  2. #2
    Join Date
    Kali forums
    What's the nmap command you are running? Depending on the scan, it may take awhile.

    Try changing the timing option (-T). I think the default is 3, but try upping it to 4 and see what happens.

    It looks like the transmit power on your wireless card is pretty low. If your wireless card supports it, upping the transmit power may help also.

  3. #3
    Join Date
    Hi grid, thanks for the response, I'm running the following command:
    If I try with -T4/-T5 flags it still takes at least 10 minutes to complete.

    For increasing the power do you mean running:
    iwconfig wlan0 txpower 30
    Or by using another command?

    Thanks again.

  4. #4
    Join Date
    Kali forums
    No problem

    Hmm, since that's an external box, you might be having lag over the net, or DNS issues. Try using IP instead of DNS name, and see if that helps your speed. You could also try using nmap's dns parameter, set it to (Google's public DNS server).

    Yeah, that's the command on iwconfig.

  5. #5
    Join Date
    Hey grid thanks again for the suggestions, I came to the conclusion that these scans takes forever because of the router firewall, I tried to disable it and my scans now takes least than 10 seconds.
    Do you know how can I keep my firewall enabled and running nmap normally?

    On the router panel I've got the following options below "Firewall":

    • Access Control
    • MAC Filter
    • URL Blocking
    • Schedule Rule
    • Intrusion Detection
    • DMZ (Demilitarized Zone)

    Do you want that I post the available settings inside each option?

    Sorry for my English

  6. #6
    Join Date
    Kali forums
    You're very welcome!

    Unfortunately, firewall configuration is a little out of my league.

Similar Threads

  1. Kernel Extremely Slow Startup
    By Shadorain in forum TroubleShooting Archive
    Replies: 0
    Last Post: 2020-02-04, 23:02
  2. Replies: 3
    Last Post: 2018-07-19, 15:12
  3. Vega running extremely slow with 2GB of RAM, VMWare
    By thomja in forum General Archive
    Replies: 0
    Last Post: 2015-09-28, 12:33

Tags for this Thread

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts