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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.

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Why the heck are your TXT records this large? – mdpc Dec 19 '12 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 '12 at 22:34
For dns responses larger than 512bytes you (often) need tcp/53. Is that port allowed in your ACL? – Zabuzzman May 8 '13 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 '13 at 11:00
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 '14 at 20:21

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.

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