Check for running DHCP daemon?

Jason Bailey jbailey at emerytelcom.com
Fri Jan 23 17:02:32 CET 2015


Hmm, okay. What you are saying makes sense.

I'm actually wondering if it might be more beneficial for me to check if 
the local DHCP port (udp 67) is bound and in use. I had tried to do this 
some time ago, and couldn't get it working right (it would always test 
true, even when it shouldn't have). Can anyone steer me in the right 
direction on port status?

Jason Bailey
Network Technician
Emery Telcom
Office: (435) 636-0052
JBailey at emerytelcom.com

On 01/21/2015 09:39 PM, Chris Angelico wrote:
> On Thu, Jan 22, 2015 at 2:58 PM, Jason Bailey <JBailey at emerytelcom.com> wrote:
>> How would I get a list of running processes with the subprocess module? The
>> documentation wasn't clear to me.
> Using the ps command. :)
>
> rosuav at dewey:~$ python3
> Python 3.4.2 (default, Oct  8 2014, 10:45:20)
> [GCC 4.9.1] on linux
> Type "help", "copyright", "credits" or "license" for more information.
>>>> import subprocess
>>>> b" dhcpd\n" in subprocess.check_output(["ps","-A"])
> False
>
> rosuav at sikorsky:~$ python3
> Python 3.5.0a0 (default:4709290253e3, Jan 20 2015, 21:48:07)
> [GCC 4.7.2] on linux
> Type "help", "copyright", "credits" or "license" for more information.
>>>> import subprocess
>>>> b" dhcpd\n" in subprocess.check_output(["ps","-A"])
> True
>
> There's a DHCP server running on Sikorsky, but not on Dewey. :)
>
> Of course, this can be faked. Any process can call itself 'dhcpd' and
> pretend to be the DHCP server. It's up to you to decide how to deal
> with that. (Probably by not caring, I would expect. Unless you
> actually expect someone to maliciously try to confuse your script,
> it's not worth the hassle of protecting yourself.)
>
> ChrisA

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-list/attachments/20150123/e35254f2/attachment.html>


More information about the Python-list mailing list