I just managed to nail down a problem that appears every now and then
with name resolution. One of our name servers - the first listed in
resolv.conf - is currently down and I was not able to resolve anything
until I changed the order of the nameserver entries in resolv.conf.
Before I did that e.g.
ping www.uni-hamburg.de
just gave me
ping: unknown host www.uni-hamburg.de
after a decent while.
I always thought that the nameserver entries are tried subsequently
until one try succeeds or there is none left and that's what the
resolv.conf man page says, too:
[...]
use the name server on the local machine. (The
algorithm used is to try a name server, and if the
query times out, try the next, until out of name
servers, then repeat trying all the name servers
until a maximum number of retries are made).
[...]
Just for completeness, my (fairly simple) resolv.conf
domain dkrz.de
nameserver 136.172.100.240 136.172.60.68 136.172.60.241
So, am I missing something? Am I doing something wrong?
Some additional remarks:
The name server is not really down, but under maintainance and not
accepting any connections.
An nslookup gives:
gp12:~>nslookup
> set debug
> server 136.172.100.240
> www.uni-hamburg.de
;; res_mkquery(0, www.uni-hamburg.de, 1, 1)
;; res_send()
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 337
;; flags: rd; Ques: 1, Ans: 0, Auth: 0, Addit: 0
;; QUESTIONS:
;; www.uni-hamburg.de, type = A, class = IN
;; Querying server (# 1) udp address = 136.172.100.240
136.172.100.240 recvfrom: Connection timed out
;; Querying server (# 1) udp address = 136.172.100.240
136.172.100.240 recvfrom: Connection timed out
;; res_send failed
Nameserver niesel.dkrz.de not responding
www.uni-hamburg.de A record not found at niesel.dkrz.de, try again
Regards,
Andree
--
| Institute of Geophysics phone: +49 40 4123 4389
ANDREE LEIDENFROST | University of Hamburg fax: +49 40 4123 5441
Geophysicist | Bundesstrasse 55 e-mail: [EMAIL PROTECTED]
| D-20146 Hamburg www: www.app-geoph.dkrz.de
--
TO UNSUBSCRIBE FROM THIS MAILING LIST: e-mail the word "unsubscribe" to
[EMAIL PROTECTED] .
Trouble? e-mail to [EMAIL PROTECTED] .
