I think I remember reading somewhere that the Cisco best practice was to set the ironport to use root dns servers. From the best that I can tell, the ironport uses the root dns servers to get the name servers of the domain in the email and then it queries that domains nameservers for the DKIM txt record. It appears that if the txt record returns additional nameservers in the answer then the ironport will query the additional nameservers for the DKIM key even if it received it in the first response. I opened a case with TAC to see if this is a bug. I think any domain with 5 or more nameservers creates a tempfail on the DKIM query. ... View more

What I am seeing now is that this is just not AOL domains. In wireshark the txt query response includes additional nameservers and it appears that the ironport is stopping after so many nameserver replies.  ... View more

Actually I am not using internal DNS. I have the option checked in the ironports to use root dns and this is when the failure occurs. If I use internal DNS or the ISP DNS the the query to the txt record works. ... View more

Ok, thanks for the clarification. So do I need to trunk the wired vlan that is acting as the airplay server on the WLC or just enable snooping?  ... View more

Ah, yes that makes sense. Once I hit the router interface then the vlan tag disappears. So it sounds like either the auto qos is applying the DCSP bit and using it from start to finish, or it's adding this at the L3 boundary. I guess I could mirror the L2 interface and check to see if the pbit is in the vlan tag there and the L3 marking as well.   Regardless of L2 or L3 markings, I guess it depends on what the switch or router does with this, correct? I assume just because I see it doesn't mean it will get utilized.   I feel pretty comfortable with the fiber switch actions. It will basically look at the L3 bit, map it to a switch queue,  and then process these as high priority. It sounds like from what you are saying above that the 3750 can do this l3 to l2 mapping as well, but what auto Qos voice does is up in the air. I guess I need to look up what auto Qos actually does. Thanks for your help on this! ... View more

Hi Joseph,   Thanks for the info! Yes, the p-bit that I am referring to is in the vlan portion and is defined in the 802.1p standard. I didn't see this info in my capture, but I was capturing on the fiber switch side.    I know my fiber switch will honor the L3 qos and basically map it to a queue and depending on the marking it will prioritize the frame accordingly.   I guess I need to capture on the 3750 and look at my voice vlan to see what's happening there. Since it's at layer 2 I assume it's using 802.1p unless Cisco is doing something different with their auto Qos. ... View more