DNS questions for Cisco IOS DNS server

  • Caching:  Does the IOS DNS server cache TXT and SRV records?  How about negative caching (DNS NCACHE, RFC2308)?
    • ANSWER (partial):  Yes, it appears that at the very least it supports caching of TXT and SRV records.
  • Which provides better DNS behavior for clients – assigning a search list to the client, or having the router act as a forwarder and check the search domains itself?  Pros and cons for each?
    • ANSWER (partial):  It doesn’t appear that IOS actually postpends the search suffixes for some reason.  Eventually I will go back and attempt to address this; at the moment I suspect it’s my configuration rather than a Cisco bug, but as easy as it seems to be to hit bugs in IOS code anymore, I won’t completely rule that out.

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