Setup instructions

[paulng30]

Hi,

I apologize I'm not well verse with Linux. Could you please provide instructions how to set this up from start? Where can we place these files once they are downloaded? Thank you very much!

[LoH-lu]

I will update the wiki to be more clear.
You can just create a folder in your home directory, it's enough to start with.

[paulng30]

Hi LoH-lu,

Scripts work good, except I noticed whenever scan runs, it causes the end-devices to go offline for couple of seconds. I watched the switch ports of the end-device while scanning, they show "INCOMPLETE". Not sure if this is because the level and nmap scan that we use. I wonder if we can tune it down a little bit. Like only nmap scan on one particular port 443. What's your thoughts?

[LoH-lu]

Hey,

This is the nmap command being run "nmap -sn -R -T3 --min-parallelism 10"

Ping Scan (-sn): Checks which hosts are up by sending ping requests, without scanning for open ports.
DNS Resolution (-R): Performs reverse DNS resolution on all target IPs, even those that do not respond to pings.
Normal Timing (-T3): Uses the default timing template, balancing speed and reliability.
Parallel Probes (--min-parallelism 10): Ensures at least 10 probes are active in parallel, enhancing scan speed.

I'm surprised to be honest as this nmap is not doing much.
Are all end devices going down or only specific one/brand ?

[paulng30]

hi,

Thanks for the detailed information on the nmap command. I agreed this shouldn't cause any issues. I'll run some more tests and keep you posted. I have just a handful of devices in this one subnet that I'm testing, couple of Cisco switches, some Dell laptops.

I'm curious, would it be possible for me to exclude some prefixes in the 'netbox_retrieve.py' script when it writes out to csv file? Reason is I have two locations and I would like to run these scripts in both locations and send back data to one Netbox, if all possible.

Thanks again!

[paulng30]

Found the cause of that issue and corrected it. There was a loop on that test subnet.

[LoH-lu]

hi,

Thanks for the detailed information on the nmap command. I agreed this shouldn't cause any issues. I'll run some more tests and keep you posted. I have just a handful of devices in this one subnet that I'm testing, couple of Cisco switches, some Dell laptops.

I'm curious, would it be possible for me to exclude some prefixes in the 'netbox_retrieve.py' script when it writes out to csv file? Reason is I have two locations and I would like to run these scripts in both locations and send back data to one Netbox, if all possible.

Thanks again!

Sorry, missed that message, i'll review that if you are still interested!

[lazirus33]

Hello, First I want to echo what the others have said and seriously thank you for creating these scripts. Total life saver, lol. I am getting an error when I get to the step for nmap_compare.py. I keep getting the below error, It looks like it is referencing a "results" folder. However I do not see that in the folder tree. I have tried creating the folder, which did not help. Any advice would be appreciated, thanks!

Traceback (most recent call last):
File "/home/skywestne/projects/netbox-nmap-scan/nmap_compare.py", line 37, in
latest_files = get_latest_files(directory)
^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/skywestne/projects/netbox-nmap-scan/nmap_compare.py", line 29, in get_latest_files
files = [f for f in os.listdir(directory) if f.endswith('.csv')]
^^^^^^^^^^^^^^^^^^^^^
FileNotFoundError: [Errno 2] No such file or directory: 'results/'
skywestne@netbox:~/projects/netbox-nmap-scan$ ls

[LoH-lu]

Ok I see now, here's the issue:

You are not using the active status ? only container ?

[lazirus33]

Im completely new to Netbox, So I was following a walkthrough on the proper steps with setting up the ipam portion. They were saying to set your prefixes as container. I probably did it wrong, lol. Sorry, im going to go back through and change it. Ill keep you posted, thanks again!

[LoH-lu]

You can keep your /8, /16 as container (supernet)
Personnally we use Active as the end prefix, meaning there will be not other prefixes bellow

But tell me what you prefer, i can do a fix just for your case :)

[lazirus33]

That actually makes more sense to me, I had it that way to begin with and then changed it after the walkthrough, lol. Testing it now

[lazirus33]

You are awesome!! That worked. Thank you so much for the assistance with this. Great work!

[MROSSFTEK]

i just pulled your scripts down and ran that multi DNS file and its asking for a csv.. did i miss in the instructions where it tells you how to make that csv?

[LoH-lu]

Hey, yup you'll need to follow this:
https://github.com/LoH-lu/netbox-nmap-scan/wiki/How-to-run-%3F
The csv is created after you run netbox_retrieve.py (don't forget to fill out var.ini with your own Netbox details)

[luis15pt]

Similar issue my ipam_prefixes.csv is not filled?
Prefix,VRF,Status,Tags,Tenant

Am i missing something from netbox?

[LoH-lu]

Hey, run the netbox_retrieve.py and see if the prefixes csv file is filled up or not.
Once you run the scan and the scan is finished, the prefixes that have been scanned get removed from the prefixes csv file.
Let me know if that help

[luis15pt]

Found the issue the script looks for IPAM -> Prefixes that was empty

[LoH-lu]

Ah yes of course! Good catch ;)

[luis15pt]

Also documentation doesn't mention that it needs nmap installed,

sudo apt install nmap

[LoH-lu]

Thanks! Added to the wiki