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
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@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@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@ng-voice.com wrote:
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@gmail.com:
It was the port in the LCR table! You're the man! Thanks so much for your help.
On Mon, Jan 23, 2017 at 12:45 AM, Carsten Bock carsten@ng-voice.com wrote:
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Carsten Bock -
Jeremy Gadd