Am Samstag, 28. Dezember 2013, 11:05:33 schrieb Tomasz Sterna:
> Dnia 2013-12-28, sob o godzinie 09:10 +0100, Eric Koldeweij pisze:
> > My suspicion is that there is a problem with a name server you are
> > using. if you look at the file /etc/resolv.conf you will see one or
> > more lines saying "nameserver <ip_addr>". The resolver will ask each
> > name server in turn to resolve the host name for it,
> 
> I second that. This is what immediately came to my mind as a probable
> answer to your issue.
 
No, this is not it. My /etc/resolv.conf contains only one line, and it is

nameserver 8.8.8.8

Both dig and host can use this nameserver to resolve the names in question 
with very little delay:

$ time host -t SRV _xmpp-server._tcp.jabber.org. 8.8.8.8
Using domain server:
Name: 8.8.8.8
Address: 8.8.8.8#53
Aliases: 

_xmpp-server._tcp.jabber.org has SRV record 30 30 5269 hermes2.jabber.org.
_xmpp-server._tcp.jabber.org has SRV record 31 30 5269 hermes2v6.jabber.org.

real    0m0.034s
user    0m0.000s
sys     0m0.020s

$ time host -t SRV _xmpp-server._tcp.jabber.ccc.de. 8.8.8.8
Using domain server:
Name: 8.8.8.8
Address: 8.8.8.8#53
Aliases: 

_xmpp-server._tcp.jabber.ccc.de has SRV record 5 0 5269 jabberd.jabber.ccc.de.

real    0m0.034s
user    0m0.000s
sys     0m0.020s

$ time dig -t srv _xmpp-server._tcp.jabber.org.

; <<>> DiG 9.9.3-P2 <<>> -t srv _xmpp-server._tcp.jabber.org.
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 28840
;; flags: qr rd ra; QUERY: 1, ANSWER: 2, AUTHORITY: 0, ADDITIONAL: 1

;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 512
;; QUESTION SECTION:
;_xmpp-server._tcp.jabber.org.  IN      SRV

;; ANSWER SECTION:
_xmpp-server._tcp.jabber.org. 247 IN    SRV     30 30 5269 hermes2.jabber.org.
_xmpp-server._tcp.jabber.org. 247 IN    SRV     31 30 5269 
hermes2v6.jabber.org.

;; Query time: 10 msec
;; SERVER: 8.8.8.8#53(8.8.8.8)
;; WHEN: Sat Dec 28 14:07:01 CET 2013
;; MSG SIZE  rcvd: 135


real    0m0.035s
user    0m0.020s
sys     0m0.000s

> "dig" command works independently of stub resolver in your system and is
> more of a DNS servers test tool, not your system setup test tool.
> 
> Take a look at each of your 'nameserver' line in /etc/resolv.conf and
> check each server first pinging it, then asking directly:
> 
> host -t SRV _xmpp-server._tcp.jabber.org. dns.server.ip.123

See above, resolving these names with either dig or host works fine, using the 
nameserver from /etc/resolv.conf

I just ran tcpdump while restarting jabberd, this is what I saw (excerpt):

14:19:06.638847 IP 62.48.88.30.47380 > 8.8.8.8.domain: 35840+ [1au] SRV? 
_xmpp-server._tcp.jabber.org. (57)
14:19:06.644226 IP 62.48.88.30.47380 > 8.8.8.8.domain: 32182+ [1au] SRV? 
_xmpp-server._tcp.jabber.eof.name. (62)
14:19:06.646615 IP 62.48.88.30.47380 > 8.8.8.8.domain: 34426+ [1au] SRV? 
_xmpp-server._tcp.freistaat-linden.de. (66)
14:19:06.648101 IP 8.8.8.8.domain > 62.48.88.30.47380: 35840 2/0/1 SRV 
hermes2v6.jabber.org.:5269 31 30, SRV hermes2.jabber.org.:5269 30 30 (135)
14:19:06.654613 IP 8.8.8.8.domain > 62.48.88.30.47380: 32182 NXDomain 0/1/1 
(119)

So there is an answer at least for one of the requests (jabber.org), but 
jabberd2 still says

Dec 28 14:21:02 blish jabberd/s2s[14802]: dns lookup for jabber.org timed out

in its logs.

        Guido
        Guido



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