topic Re: DNS UDP datagram size in Network Security https://community.cisco.com/t5/network-security/dns-udp-datagram-size/m-p/803723#M969987 <HTML><HEAD></HEAD><BODY><P>Security-525(config)# policy-map type inspect dns migrated_dns_map_1</P><P></P><P>Security-525(config-pmap)# parameters</P><P></P><P>Security-525(config-pmap-p)# message-length maximum 1024</P><P></P></BODY></HTML> Mon, 18 Feb 2008 22:50:51 GMT abinjola 2008-02-18T22:50:51Z DNS UDP datagram size https://community.cisco.com/t5/network-security/dns-udp-datagram-size/m-p/803720#M969984 <P>Hello,</P><P></P><P>The default policy on an ASA firewall is to drop DNS UDP datagrams larger than 512 bytes. Have you modified this policy? We had quite some DNS root-servers sending UDP packets of 541 bytes. Is there som general recommendation?</P><P></P><P>Best regards,</P><P>Rutger Blom </P> Mon, 11 Mar 2019 11:07:12 GMT https://community.cisco.com/t5/network-security/dns-udp-datagram-size/m-p/803720#M969984 Rutger Blom 2019-03-11T11:07:12Z Re: DNS UDP datagram size https://community.cisco.com/t5/network-security/dns-udp-datagram-size/m-p/803721#M969985 <HTML><HEAD></HEAD><BODY><P>I allways increase this number to 1024.</P><P></P></BODY></HTML> Thu, 06 Sep 2007 13:23:00 GMT https://community.cisco.com/t5/network-security/dns-udp-datagram-size/m-p/803721#M969985 a.alekseev 2007-09-06T13:23:00Z Re: DNS UDP datagram size https://community.cisco.com/t5/network-security/dns-udp-datagram-size/m-p/803722#M969986 <HTML><HEAD></HEAD><BODY><P>I know this is an old post and my question relates to IOS Firewall. How do you change the DNS UPD packet size on an IOS firewall?</P><P></P><P>I know how to do this on a PIX, but not on the IOS firewall.</P><P></P><P>Thanks.</P></BODY></HTML> Mon, 18 Feb 2008 20:48:30 GMT https://community.cisco.com/t5/network-security/dns-udp-datagram-size/m-p/803722#M969986 adrianotte 2008-02-18T20:48:30Z Re: DNS UDP datagram size https://community.cisco.com/t5/network-security/dns-udp-datagram-size/m-p/803723#M969987 <HTML><HEAD></HEAD><BODY><P>Security-525(config)# policy-map type inspect dns migrated_dns_map_1</P><P></P><P>Security-525(config-pmap)# parameters</P><P></P><P>Security-525(config-pmap-p)# message-length maximum 1024</P><P></P></BODY></HTML> Mon, 18 Feb 2008 22:50:51 GMT https://community.cisco.com/t5/network-security/dns-udp-datagram-size/m-p/803723#M969987 abinjola 2008-02-18T22:50:51Z