DNS problems to RoadRunner - tcp vs udp

Bill Owens owens at nysernet.org
Fri Jun 13 13:33:57 CDT 2008


On Fri, Jun 13, 2008 at 02:14:55PM -0400, Jon Kibler wrote:
> -----BEGIN PGP SIGNED MESSAGE-----
> Hash: SHA1
> 
> Mark Price wrote:
> <SNIP>
> >>From what I have read, public DNS servers should support both UDP and
> > TCP queries.  TCP queries are often used when a UDP query fails, or if
> > the answer is over a certain length.
> > 
> 
> UDP is used for queries.
> 
> TCP is used for zone transfers.
> 
> If my server responded to TCP queries from anyone other than a secondary
> server, I would be VERY concerned.

Red alert:

[cookiemonster:~] owens% dig +tcp aset.com @209.190.93.130 soa

; <<>> DiG 9.4.2 <<>> +tcp aset.com @209.190.93.130 soa
;; global options:  printcmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 5864
;; flags: qr aa rd; QUERY: 1, ANSWER: 1, AUTHORITY: 5, ADDITIONAL: 2
;; WARNING: recursion requested but not available

;; QUESTION SECTION:
;aset.com.			IN	SOA

;; ANSWER SECTION:
aset.com.		14400	IN	SOA	ns1.sims.net. hostmaster.aset.com. 2006111001 10800 3600 3600000 86400

;; AUTHORITY SECTION:
aset.com.		14400	IN	NS	ns3.trustns.net.
aset.com.		14400	IN	NS	ns1.sims.net.
aset.com.		14400	IN	NS	ns1.trustns.net.
aset.com.		14400	IN	NS	ns2.sims.net.
aset.com.		14400	IN	NS	ns2.trustns.net.

;; ADDITIONAL SECTION:
ns1.sims.net.		86400	IN	A	209.190.93.130
ns2.sims.net.		86400	IN	A	209.190.93.132

;; Query time: 31 msec
;; SERVER: 209.190.93.130#53(209.190.93.130)
;; WHEN: Fri Jun 13 14:31:13 2008
;; MSG SIZE  rcvd: 211


Bill.




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