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I have two virtual machines that are and in an ESX. I try to access theses machines by another network

The problem is that when I can ping one machine, I can not ping the other one. And conversely.

Me -> A : Yes

Me -> B : No


Me -> A : No

Me -> B : Yes

The machines have different IP addresses and different MAC addresses.

I can not understand what is happenning right here.

Note : When a machine can not be ping, it can not ping its gateway.

Note 2 : When a machine can not be ping, I can not see any traffic comming whith a tcpdump.

Note 3 : Everything is right regarding the firewalls between my networks.

Could you please help me ?

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These are two separate VMs, you are sure? What OS? How are you "accessing the machines". What NIC driver is used? – user160910 Apr 18 '13 at 15:22
Your title says "MAC conflict" but then your description says that there isn't one. Which statement is accurate? – MDMarra Apr 18 '13 at 15:23
Because I think that this is a MAC conflict but I'm really not sure of that. These are two seperate VMS for sure. 2008R2 and Debian. When I say access I mean ping. – Elwyn Apr 18 '13 at 15:42
Where are you getting the idea of a MAC address conflict from? Have you checked the mac addresses on the guest OS and ESXi? Remember that the machines on the 192.168 network will only see the router MAC. – Dan Apr 18 '13 at 15:45
P.S., it sounds to me like you're diagnosing this the wrong way round. If a machine can not ping it's default gateway then you're NEVER going to be able to speak to it from a different network. The issues are all on the 10.1 side and you need to figure out what's happening between the guest and the gateway. – Dan Apr 18 '13 at 15:46

Problem was port-security. Only one MAC address was allowed to use the port. Set to more than one.

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