Received response from host (router IP address) with invalid source port 32784

Question

I replaced my old wireless router with a Cisco Linksys E4200, running firmware version 1.0.02 build 13  May 24, 2011.  About once a minute the router sends an unsolicited DNS message to the IPV4 multicast address 01:00:5e:00:00:fb with a destination IP address of 224.0.0.251.  The unsolicited message is a DNS response with source port 32784, transaction ID 0, flags 0x8400 (standard query response, no error), questions 0, answer RRs 2, authority RRs 0 and additional RRs 1.  The two answers both relate to the router itself: one has Name Cisco18738.local, type A (host address), class 1 (IN), cache flush true, time to live 1 minute, data length 4, and the address of the router.  The other is the reverse of the same address.  The additional record is for Cisco18738.local, type NSEC, class IN, cache flush true, time to live 1 minute, data length 5, next domain name Cisco18738.local, RR type A (host address).
When my desktop computer receives these messages it logs an error, for example: "Jun 23 07:39:22 sauterws02 avahi-daemon[1067]: Received response from host 10.146.9.1 with invalid source port 32784 on interface 'eth0.0'"  The 10.146.9.1 is the router's IP address.  I also see these messages on the wireless link from my laptop.
I suppose the E4200 is generating these DNS messages in a misguided attempt to make sure there is no old information about its name.  Is there a way to turn them off?  If not, is there a way to report this to Cisco as a bug?
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Answer 1

gv wrote:
1. To contact Linksys, call support.
2. From the internet draft: "Multicast DNS implementations MUST
silently ignore any Multicast DNS Responses they receive where the
source UDP port is not 5353." Your avahi-daemon does not comply with this draft.
Thank you for the reference.  For the sake of others who may read this thread, the current draft of multicast DNS is at http://www.ietf.org/id/draft-cheshire-dnsext-multicastdns-14.txt. 
Here is the whole paragraph from which you quoted, from section 6 (Responding): "The source UDP port in all Multicast DNS Responses MUST be 5353 (the well-known port assigned to mDNS). Multicast DNS implementations MUST silently ignore any Multicast DNS Responses they receive where the source UDP port is not 5353."
Thus, it appears that there are two errors here: the Cisco E4200 is not using 5353 as the source port, and the logger is not silently ignoring it.
The message appears to be an announcement rather than an actual response to a query.  In section 8.3 (Announcing) I found this paragraph: "A Multicast DNS Responder MUST NOT send announcements in the absence of information that its network connectivity may have changed in some relevant way. In particular, a Multicast DNS Responder MUST NOT send regular periodic announcements as a matter of course."  Thus, it appears that there are three errors here.