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 Post subject: A real head scratcher
PostPosted: Wed May 09, 2012 9:40 pm 
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So i have sifted through a hundred or so topics on here and haven't found anything related to the problem that i am experienceing.

Here is the quick and dirty of the situation.

There are a few workstations connecting to a couple of switches that connect back to the router. The workstations are unable to connect back to a fileserver and all ping attempts fail. How ever when i ping the server from the switch it hits it every time. I did a test of 10,000 ping to the server from the switch and not a single one failed. I also pinged the workstation from the switch the same number of times and same thing not one dropped. I also pinged the workstation from another computer that is on a different subnet and only lost 3 out of 5,000 packets.

The network that these machines are on is a staticaly routed network and i verifed all the proper routes are in the router. Also the computers have been checked to make sure that the NIC drivers are current. So I am at a loss to think of what could be causing this. If you guys and gals can think of anything that might be causing this issue it would be greatly appreciated.

Thanks


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PostPosted: Thu May 10, 2012 2:12 am 
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Impossible to know without knowing your IP structure or how things are routed. Is this a layer3 switch? What does a traceroute show?

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PostPosted: Thu May 10, 2012 6:59 am 
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have you checked to see if the windows firewall is turned on ?


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 Post subject: A real head scratcher
PostPosted: Thu May 10, 2012 11:07 am 
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Maybe an ACL in the way somewhere?


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PostPosted: Sun May 13, 2012 12:17 am 
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Provide a network topography of some kind? I am sure there is an easy as pie answer but not without a painted picture of your network you are troubleshooting.

What switch are you on?
What router are you using, and how many?
How is the server connected to the switches/router?
What did you have for lunch?
What kind of car do you drive?
And what is your favorite beer?

Ok the last 3 are not important haha

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PostPosted: Mon May 14, 2012 8:17 am 
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Even if this was a flat network you need to verify that when you ping a device that your packet is communicating with the correct upstream (or next hop) devices mac address, and that some other device is not interfering with the communication. An example of this would be proxy arp, or a duplicate IP of some kind. Have seen this so many many times and it often catches out server guys.

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