3

Is it possible to increase the maximum record size/cache size supported by the DNS server embedded in a Cisco 800 series router (886VA in my case)? I cannot query large (1500b) TXT records without bypassing Cisco's ip dns server.

Improve this question
5
  • Why the heck are your TXT records this large?
    – mdpc
    Dec 19, 2012 at 21:47
  • Some embedded systems have limited methods of configuration (or set modes in this case) and sometimes you end up with horrible kludges to make things work "just right".
    – Metalshark
    Dec 19, 2012 at 22:34
  • 1
    For dns responses larger than 512bytes you (often) need tcp/53. Is that port allowed in your ACL?
    – Zabuzzman
    May 8, 2013 at 20:37
  • @Zabuzzman yup TCP 53 is enabled, and according to a network TAP installed it is actively used as well. The limit appears to be 1300b records and above.
    – Metalshark
    May 20, 2013 at 11:00
  • 1
    Stupid question -why do you not just use a real dns server? I have all kinds of routers in my networks but I never use the router as dns SERVER.
    – TomTom
    Feb 2, 2014 at 20:21

1 Answer 1

Reset to default
1

Call Cisco and mention to them that it's 2014, and perhaps they should support EDNS0, which has only been around for 10 years now.

Improve this answer

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .