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Detect duplicated gateway ips

ngf detect duplicated ips ip-conflict

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3 replies to this topic

#1 Bernhard Neuner

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Posted 06 May 2017 - 05:33 AM



we ran into a problem with a NGF in a customers LAN - the site-2-site vpn tina tunnel was totally unstable. Most of the other clients on the LAN (mostly windows pcs) works fine.

Finally a tcpdump capture helped to find the cause of the problem. There was an ip-conflict in the customers LAN, we saw two MAC addresses for the configured default gateway ip on the NGF.


Would be great if NGF detects duplicated gateway IPs.


Bernhard Neuner

#2 Steve Vickers

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Posted 12 May 2017 - 03:49 AM



I believe the NGF does check for duplicate IP addresses within it's own ARP domain (as most LAN devices should). Of course, outside of that we have no way of detecting duplicate IPs.

#3 Bernhard Neuner

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Posted 09 August 2017 - 01:54 AM

Hi Steve,


The problem occurred in the same ARP domain

#4 Micha Knorpp

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Posted 10 August 2017 - 09:48 AM

Strange, the NG does definitely detect duplicate IPs....

which release version was that?