ESXi 5.0 AD Auth outgoing port 51915?

[DSeaman]

I was configuring one of our ESXi 5.0 hosts for AD authentication, when I decided to take a peek at the new firewall rules that enabling the AD service created. What I found was a slew of ports I would expect (88, 445, 3268, etc.) but I did see one oddball: 51915. I looked at the VMware KB article that lists all of the ports/protocols for VMware products and there's not a single mention of 51915.

Can anyone enlighten me why the ESXi 5.0 host enabled outgoing port 51915 when you turn on AD authentication? I realize it's just an outgoing port rule, so the host isn't listening, but it still seemed a bit odd to me. Is it related to the new ESXi authentication proxy feature? 

[Texiwill]

Hello,

This is a first one for me as well.  I would open up a service request with VMware to get them to tell you why it is open or disable it yourself and get them to change the default AD rules. VMware uses the Likewise module (now from Beyond Trust) to do AD Integration, you may also want to check with them.

Best regards,

Edward L. Haletky

Communities Moderator, VMware vExpert,

Author: VMware vSphere and Virtual Infrastructure Security,VMware ESX and ESXi in the Enterprise 2nd Edition

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