On 31.10.2016 16:51, Michael Davidsaver wrote:
> On 10/31/2016 11:33 AM, Benjamin Franksen wrote:
>> On 31.10.2016 15:30, Michael Davidsaver wrote:
>>> On 10/31/2016 07:09 AM, Benjamin Franksen wrote:
>> Anyway, this sort of problem (duplicate IP adresses) should be detected
>> automatically by the network infrastructure IMO, and not left to be
>> debugged by control system engineers after they lead to obscure CA
>> connection failures.
>
> Oh, I completely agree! However, I've been bitten by this, so I know
> that detection (or notification of detection) isn't 100%. I happened to
> notice that the MAC in the arp cache was alternating between two values.
Uargh. That would indeed be hard to detect automatically.
> some relevant links
>
> https://linux.die.net/man/8/arping
>
> http://ipwatchd.sf.net
Thanks for the links. A colleague found a tool named arp-scan, which can
be used to implement a simple test:
franksen@tiber > sudo arp-scan -l | grep DUP:
193.149.12.195 00:06:71:33:00:d4 Softing AG (DUP: 2)
193.149.12.196 00:06:71:33:00:d4 Softing AG (DUP: 2)
The tool is packaged in common distros (debian,ubuntu,fedora).
I am currently in the process of trying to get this to run as a test
script for icinga on all our control networks, so perhaps next time we
will be warned earlier...
Cheers
Ben
--
"Make it so they have to reboot after every typo." ― Scott Adams
Attachment:
signature.asc
Description: OpenPGP digital signature
- Replies:
- Re: CA connection problems between VxWorks and Windows Michael Davidsaver
- References:
- CA connection problems between VxWorks and Windows Benjamin Franksen
- Re: CA connection problems between VxWorks and Windows Benjamin Franksen
- Re: CA connection problems between VxWorks and Windows Michael Davidsaver
- Re: CA connection problems between VxWorks and Windows Benjamin Franksen
- Re: CA connection problems between VxWorks and Windows Michael Davidsaver
- Navigate by Date:
- Prev:
Re: CA connection problems between VxWorks and Windows Michael Davidsaver
- Next:
Re: CA connection problems between VxWorks and Windows Michael Davidsaver
- Index:
1994
1995
1996
1997
1998
1999
2000
2001
2002
2003
2004
2005
2006
2007
2008
2009
2010
2011
2012
2013
2014
2015
<2016>
2017
2018
2019
2020
2021
2022
2023
2024
- Navigate by Thread:
- Prev:
Re: CA connection problems between VxWorks and Windows Michael Davidsaver
- Next:
Re: CA connection problems between VxWorks and Windows Michael Davidsaver
- Index:
1994
1995
1996
1997
1998
1999
2000
2001
2002
2003
2004
2005
2006
2007
2008
2009
2010
2011
2012
2013
2014
2015
<2016>
2017
2018
2019
2020
2021
2022
2023
2024
|