[SR-Users] NAPTR/SRV lookups fail when use_dns_failover is enabled.
Carsten Bock
carsten at ng-voice.com
Mon Jan 23 08:45:17 CET 2017
Hi,
can you try the sip-dig command on that particular domain?
If you set that domain in script or from a module (e.g. Dispatcher),
don't set a port. According to RFC 3263, the DNS-records are treated
differently, if no port is set (e.g. "redacted.hostname.here.com:5060"
will produce a different result than "redacted.hostname.here.com").
I've checked the compliance of Kamailio with RFC 3263 in the past, as
DNS-Failover is mandatory for IMS.
I would find it rather strange, if it should work correct in all of
our deployments and not in yours.
Thanks,
Carsten
2017-01-20 17:47 GMT+01:00 Jeremy Gadd <jeremygadd at gmail.com>:
> Thanks for the response!
>
> DNS lookups work in Kamailio as long as use_dns_failover is set to "off."
> It's only when the failover is enabled that they break. I think this means
> it's not a DNS issue, but something in Kamailio.
>
> I should mention we're pointing to Verizon's services with many many
> thousands of customers, so it's unlikely to be misconfigured DNS (unless
> it's something local that only breaks when use_dns_failover is enabled?)
>
> On Fri, Jan 20, 2017 at 12:37 AM, Carsten Bock <carsten at ng-voice.com> wrote:
>>
>> Hi,
>>
>> we have the following settings and those work fine for us (Kamailio 4
>> and later):
>>
>> # Do SRV-Loadbalancing:
>> dns_srv_lb=yes
>> # Always prefer IPv6:
>> dns_try_ipv6=yes
>> # DNS-Based failover
>> use_dns_failover=yes
>> # Query NAPTR-Records as well (we use NAPTR, so the client can detect
>> the outbound Proxy (P-CSCF), but internally we only use only
>> SRV-records)
>> dns_try_naptr=no
>>
>> Sounds to me, like a DNS problem, not a Kamailio problem.
>>
>> In our DNS Zone, we have the following, for example:
>>
>> wt 1D IN A 84.46.93.82
>> wt 1D IN A 84.46.93.84
>> wt-1 1D IN A 84.46.93.82
>> wt-2 1D IN A 84.46.93.84
>> wt 1D IN NAPTR 10 10 "s" "SIP+D2U" ""
>> _sip._udp.wt
>>
>> _sip._udp.wt 1D SRV 10 1 5060 wt-1
>> _sip._udp.wt 1D SRV 20 1 5060 wt-2
>>
>> On Debian/Ubuntu, you can verify this with Sofia-SIP (apt-get install
>> sofia-sip-bin):
>>
>> carsten at carsten-HP-EliteBook-840-G3:~$ sip-dig wt.ng-voice.com
>> 1 1.000 udp 5060 84.46.93.82
>> 2 1.000 udp 5060 84.46.93.84
>>
>> Thanks,
>> Carsten
>>
>>
>> 2017-01-19 22:58 GMT+01:00 Jeremy Gadd <jeremygadd at gmail.com>:
>> > Hello, everyone!
>> >
>> > I'm trying to enable dns_srv_lb but I'm stuck just before I can get
>> > there.
>> > If I don't enable use_dns_failover, lookups work and calls route but
>> > always
>> > to the first host. We need to load balance, so that doesn't work very
>> > well.
>> >
>> > If I enable use_dns_failover, the lookups stop working completely and we
>> > get
>> > a dns lookup failure like so:
>> > ERROR: tm [ut.h:296]: uri2dst2(): ERROR: uri2dst: failed to resolve
>> > "redacted.hostname.here.com" :unresolvable A or AAAA request (-7)
>> >
>> > This works:
>> > use_dns_cache=on
>> > dns_use_search_list=no
>> > dns_try_naptr=on
>> > # use_dns_failover=on
>> >
>> > This breaks it:
>> > use_dns_cache=on
>> > dns_use_search_list=no
>> > dns_try_naptr=on
>> > use_dns_failover=on
>> >
>> > I have checked to see that use_dns_failover is compiled in:
>> > version: kamailio 4.4.2 (x86_64/linux)
>> > flags: STATS: Off, USE_TCP, USE_TLS, USE_SCTP, TLS_HOOKS, USE_RAW_SOCKS,
>> > DISABLE_NAGLE, USE_MCAST, DNS_IP_HACK, SHM_MEM, SHM_MMAP, PKG_MALLOC,
>> > Q_MALLOC, F_MALLOC, TLSF_MALLOC, DBG_SR_MEMORY, USE_FUTEX,
>> > FAST_LOCK-ADAPTIVE_WAIT, USE_DNS_CACHE, USE_DNS_FAILOVER, USE_NAPTR,
>> > USE_DST_BLACKLIST, HAVE_RESOLV_RES
>> > ADAPTIVE_WAIT_LOOPS=1024, MAX_RECV_BUFFER_SIZE 262144, MAX_LISTEN 16,
>> > MAX_URI_SIZE 1024, BUF_SIZE 65535, DEFAULT PKG_SIZE 8MB
>> > poll method support: poll, epoll_lt, epoll_et, sigio_rt, select.
>> > id: unknown
>> > compiled with gcc 4.9.2
>> >
>> > _______________________________________________
>> > SIP Express Router (SER) and Kamailio (OpenSER) - sr-users mailing list
>> > sr-users at lists.sip-router.org
>> > http://lists.sip-router.org/cgi-bin/mailman/listinfo/sr-users
>> >
>>
>>
>>
>> --
>> Carsten Bock
>> CEO (Geschäftsführer)
>>
>> ng-voice GmbH
>> Millerntorplatz 1
>> 20359 Hamburg / Germany
>>
>> http://www.ng-voice.com
>> mailto:carsten at ng-voice.com
>>
>> Office +49 40 5247593-40
>> Fax +49 40 5247593-99
>>
>> Sitz der Gesellschaft: Hamburg
>> Registergericht: Amtsgericht Hamburg, HRB 120189
>> Geschäftsführer: Carsten Bock
>> Ust-ID: DE279344284
>>
>> Hier finden Sie unsere handelsrechtlichen Pflichtangaben:
>> http://www.ng-voice.com/imprint/
>>
>> _______________________________________________
>> SIP Express Router (SER) and Kamailio (OpenSER) - sr-users mailing list
>> sr-users at lists.sip-router.org
>> http://lists.sip-router.org/cgi-bin/mailman/listinfo/sr-users
>
>
>
> _______________________________________________
> SIP Express Router (SER) and Kamailio (OpenSER) - sr-users mailing list
> sr-users at lists.sip-router.org
> http://lists.sip-router.org/cgi-bin/mailman/listinfo/sr-users
>
--
Carsten Bock
CEO (Geschäftsführer)
ng-voice GmbH
Millerntorplatz 1
20359 Hamburg / Germany
http://www.ng-voice.com
mailto:carsten at ng-voice.com
Office +49 40 5247593-40
Fax +49 40 5247593-99
Sitz der Gesellschaft: Hamburg
Registergericht: Amtsgericht Hamburg, HRB 120189
Geschäftsführer: Carsten Bock
Ust-ID: DE279344284
Hier finden Sie unsere handelsrechtlichen Pflichtangaben:
http://www.ng-voice.com/imprint/
More information about the sr-users
mailing list