[Freeswitch-users] DNS resolving for REGISTER requests

Mike Jerris mike at freeswitch.com
Mon Jun 24 13:02:48 UTC 2019


if that’s the case it’s an issue with the resolver cache in sofia-sip

On Mon, Jun 24, 2019 at 9:01 AM Sebastian Denz <denzs at gonicus.de> wrote:

> Hello Mike,
>
> thanks for getting in the discussion!
>
> I have a pcap-trace from last saturday containing sip and dns where i
> can see the following behaviour:
>
> 11:39:32 FS does an SRV-Lookup for _sip._tcp.reg.sip-trunk.telekom.de
>          -> Answer contains three records with TTL:3600
>          FS does an A-Lookup for the record with the lowest priority
>          -> Answer contains an IPv4 adress with TTL:216
>
> FS registers to the provided ip address and re-registers every ~ 5 minutes
>
> But there is no more dns traffic for the rest of the day (~ 12.5 hours)...
>
> Version is 1.8.2-3-a98a958ac3~64bit on Debian Stretch.
>
> Could this be an issue with the systems resolving logic (libnss) or is
> the resolving completly done by FS itself?
>
> Am 6/24/19 um 2:19 PM schrieb Mike Jerris:
> > if the DNS entries haven’t yet expired then freeswitch won’t query again.
> > The provider should set lower expiration on their records before a change
> > or wait the full expiration after making a change to
> > actually move hosts or they will cause this issue.  This has always been
> > how the DNS system works.
> >
> > On Mon, Jun 24, 2019 at 8:14 AM Sebastian Denz <denzs at gonicus.de> wrote:
> >
> >> That is already the case..
> >>
> >> When FS starts up it does an SRV-Lookup which contains several adresses.
> >>
> >> One thing is.. the old endpoint is still working..
> >>
> >> The provider just changes the IP behind the A record of the first SRV
> >> result.
> >>
> >> But the main problem is that FS does not use DNS at all before sending a
> >> REGISTER... So i doubt this can be workarounded without touching the
> >> code of FS or (and that is what i am going to do) use an external script
> >> to detect the change and then trigger a gateway restart in FS...
> >>
> >> Am 6/24/19 um 1:30 PM schrieb Giovanni Maruzzelli:
> >>> Maybe, just maybe, putting all addresses in srv records, FS will read
> >> that
> >>> at startup, then try them all if first fail? No idea if works... Just
> >>> curious...
> >>>
> >>>
> >>>
> >>> On Mon, Jun 24, 2019, 12:18 Sebastian Denz <denzs at gonicus.de> wrote:
> >>>
> >>>> I already thought about something like that..
> >>>>
> >>>> But the main reason for the problem seems to be, that FreeSWITCH does
> >>>> not query the dns (remote or local) at all before sending the
> >>>> REGISTER... :-/
> >>>>
> >>>> I could workaround the current issue easily by using static addresses
> >>>> but then i would loose the failover capability and i would have to
> check
> >>>> for changes manually or by script... normally dns would just solve
> that
> >>>> by itself :)
> >>>>
> >>>> I think i could put Kamailio in front of FreeSWITCH and let it handle
> >>>> the dns resolution, but that feels like using a sledgehammer to crack
> a
> >>>> nut ;)
> >>>>
> >>>> And i would prefer a tiny approach, ideally with FreeSWITCH behaving
> >>>> correctly...?!
> >>>>
> >>>> Am 6/24/19 um 12:24 PM schrieb Giovanni Maruzzelli:
> >>>>> obviously, you can locally provide dns with dnsmasq or such, easily
> >>>>> configured, for other domains too.
> >>>>>
> >>>>> Maybe you can put all SRV addresses, with different weights, in your
> >> own
> >>>>> (eg, locally defined) zone definition for deutsche telekom, and
> >>>> freeswitch
> >>>>> will try them all.
> >>>>>
> >>>>> Not sure this will work, but maybe yes :)
> >>>>>
> >>>>>
> >>>>>
> >>>>> On Mon, Jun 24, 2019 at 12:19 PM Sebastian Denz <denzs at gonicus.de>
> >>>> wrote:
> >>>>>
> >>>>>> Thank you for giving me that pointer!
> >>>>>>
> >>>>>> I thought i would have searched for everything regarding that topic,
> >>>>>> but obviously i missed that post!
> >>>>>>
> >>>>>>
> >>>>>>
> >>>>
> >>
> https://lists.freeswitch.org/pipermail/freeswitch-users/2018-January/128837.html
> >>>>>>
> >>>>>> I'll contact Kai directly as i was not able to found a corresponding
> >>>>>> issue in the tracker...
> >>>>>>
> >>>>>> But if anyone has another idea regarding the problem, i would of
> >> course
> >>>>>> appreciate any hints too! ;)
> >>>>>>
> >>>>>> Sebastian
> >>>>>>
> >>>>>> Am 6/24/19 um 11:21 AM schrieb Giovanni Maruzzelli:
> >>>>>>> I believe this question  was already asked in the past in this
> >> mailing
> >>>>>>> list, and IIRC the answer was no.
> >>>>>>>
> >>>>>>> You may wanto to check on the mailing list archives (in signature),
> >>>>>> because
> >>>>>>> maybe my merory is wrong.
> >>>>>>>
> >>>>>>> -giovanni
> >>>>>>>
> >>>>>>>
> >>>>>>> On Mon, Jun 24, 2019 at 11:14 AM Sebastian Denz <denzs at gonicus.de>
> >>>>>> wrote:
> >>>>>>>
> >>>>>>>> Hello,
> >>>>>>>>
> >>>>>>>> i am using FreeSWITCH as SBC to our SIP provider (Deutsche Telekom
> >> in
> >>>>>>>> germany).
> >>>>>>>>
> >>>>>>>> This works quite well, but ~ once in a month we are unable to do
> >>>>>>>> outbound calls.
> >>>>>>>>
> >>>>>>>> It turned out, that the provider changes some IPs from time to
> >> time..
> >>>>>>>>
> >>>>>>>> That leads to FreeSWITCH being registered to the old IP while
> >>>>>>>> INVITE-requests of new dialogs are sent to the new address. The
> >>>> provider
> >>>>>>>> terminates this with 403 - forbidden.
> >>>>>>>>
> >>>>>>>> The registration happens every 5 minutes, but FreeSWITCH does not
> >>>> update
> >>>>>>>> the dns cache for the target IP address. So i gets stuck in that
> >>>>>>>> situation being registered on the old IP while sending INVITEs to
> >> the
> >>>>>>>> new one..
> >>>>>>>>
> >>>>>>>> The only solution to that is reloading the profile or restarting
> >>>>>>>> FreeSWITCH...
> >>>>>>>>
> >>>>>>>> Is there an option to make FreeSWITCH asking the dns _before
> every_
> >>>>>>>> REGISTER? Or do you have any other suggestion on how to fix this?
> >>>>>>>>
> >>>>>>>> Best regards,
> >>>>>>>> Sebastian Denz
> >>>>>>>>
> >>>>>>>>
> >>>>>>>>
> >>>>>>>>
> >>>>>>
> >>>>
> >>
> _________________________________________________________________________
> >>>>>>>>
> >>>>>>>> The FreeSWITCH project is sponsored by SignalWire
> >>>>>> https://signalwire.com
> >>>>>>>> Enhance your FreeSWITCH install with disruptive priced SMS and
> PSTN
> >>>>>>>> services.
> >>>>>>>> Build your next product on our scalable cloud platform.
> >>>>>>>>
> >>>>>>>> Join our online community to chat in real time
> >>>>>>>> https://signalwire.community
> >>>>>>>>
> >>>>>>>> Professional FreeSWITCH Services
> >>>>>>>> sales at freeswitch.com
> >>>>>>>> https://freeswitch.com
> >>>>>>>>
> >>>>>>>> Official FreeSWITCH Sites
> >>>>>>>> https://freeswitch.com/oss
> >>>>>>>> https://freeswitch.org/confluence
> >>>>>>>> https://cluecon.com
> >>>>>>>>
> >>>>>>>> FreeSWITCH-users mailing list
> >>>>>>>> FreeSWITCH-users at lists.freeswitch.org
> >>>>>>>> http://lists.freeswitch.org/mailman/listinfo/freeswitch-users
> >>>>>>>> UNSUBSCRIBE:
> >>>>>> http://lists.freeswitch.org/mailman/options/freeswitch-users
> >>>>>>>> https://freeswitch.com
> >>>>>>>
> >>>>>>>
> >>>>>>>
> >>>>>>>
> >>>>>>>
> >>>>
> >>
> _________________________________________________________________________
> >>>>>>>
> >>>>>>> The FreeSWITCH project is sponsored by SignalWire
> >>>> https://signalwire.com
> >>>>>>> Enhance your FreeSWITCH install with disruptive priced SMS and PSTN
> >>>>>> services.
> >>>>>>> Build your next product on our scalable cloud platform.
> >>>>>>>
> >>>>>>> Join our online community to chat in real time
> >>>>>> https://signalwire.community
> >>>>>>>
> >>>>>>> Professional FreeSWITCH Services
> >>>>>>> sales at freeswitch.com
> >>>>>>> https://freeswitch.com
> >>>>>>>
> >>>>>>> Official FreeSWITCH Sites
> >>>>>>> https://freeswitch.com/oss
> >>>>>>> https://freeswitch.org/confluence
> >>>>>>> https://cluecon.com
> >>>>>>>
> >>>>>>> FreeSWITCH-users mailing list
> >>>>>>> FreeSWITCH-users at lists.freeswitch.org
> >>>>>>> http://lists.freeswitch.org/mailman/listinfo/freeswitch-users
> >>>>>>> UNSUBSCRIBE:
> >>>> http://lists.freeswitch.org/mailman/options/freeswitch-users
> >>>>>>> https://freeswitch.com
> >>>>>>>
> >>>>>>
> >>>>>>
> >>>>>>
> >>>>
> >>
> _________________________________________________________________________
> >>>>>>
> >>>>>> The FreeSWITCH project is sponsored by SignalWire
> >>>> https://signalwire.com
> >>>>>> Enhance your FreeSWITCH install with disruptive priced SMS and PSTN
> >>>>>> services.
> >>>>>> Build your next product on our scalable cloud platform.
> >>>>>>
> >>>>>> Join our online community to chat in real time
> >>>>>> https://signalwire.community
> >>>>>>
> >>>>>> Professional FreeSWITCH Services
> >>>>>> sales at freeswitch.com
> >>>>>> https://freeswitch.com
> >>>>>>
> >>>>>> Official FreeSWITCH Sites
> >>>>>> https://freeswitch.com/oss
> >>>>>> https://freeswitch.org/confluence
> >>>>>> https://cluecon.com
> >>>>>>
> >>>>>> FreeSWITCH-users mailing list
> >>>>>> FreeSWITCH-users at lists.freeswitch.org
> >>>>>> http://lists.freeswitch.org/mailman/listinfo/freeswitch-users
> >>>>>> UNSUBSCRIBE:
> >>>> http://lists.freeswitch.org/mailman/options/freeswitch-users
> >>>>>> https://freeswitch.com
> >>>>>
> >>>>>
> >>>>>
> >>>>>
> >>>>>
> >>
> _________________________________________________________________________
> >>>>>
> >>>>> The FreeSWITCH project is sponsored by SignalWire
> >> https://signalwire.com
> >>>>> Enhance your FreeSWITCH install with disruptive priced SMS and PSTN
> >>>> services.
> >>>>> Build your next product on our scalable cloud platform.
> >>>>>
> >>>>> Join our online community to chat in real time
> >>>> https://signalwire.community
> >>>>>
> >>>>> Professional FreeSWITCH Services
> >>>>> sales at freeswitch.com
> >>>>> https://freeswitch.com
> >>>>>
> >>>>> Official FreeSWITCH Sites
> >>>>> https://freeswitch.com/oss
> >>>>> https://freeswitch.org/confluence
> >>>>> https://cluecon.com
> >>>>>
> >>>>> FreeSWITCH-users mailing list
> >>>>> FreeSWITCH-users at lists.freeswitch.org
> >>>>> http://lists.freeswitch.org/mailman/listinfo/freeswitch-users
> >>>>> UNSUBSCRIBE:
> >> http://lists.freeswitch.org/mailman/options/freeswitch-users
> >>>>> https://freeswitch.com
> >>>>>
> >>>>
> >>>>
> >>>>
> >>
> _________________________________________________________________________
> >>>>
> >>>> The FreeSWITCH project is sponsored by SignalWire
> >> https://signalwire.com
> >>>> Enhance your FreeSWITCH install with disruptive priced SMS and PSTN
> >>>> services.
> >>>> Build your next product on our scalable cloud platform.
> >>>>
> >>>> Join our online community to chat in real time
> >>>> https://signalwire.community
> >>>>
> >>>> Professional FreeSWITCH Services
> >>>> sales at freeswitch.com
> >>>> https://freeswitch.com
> >>>>
> >>>> Official FreeSWITCH Sites
> >>>> https://freeswitch.com/oss
> >>>> https://freeswitch.org/confluence
> >>>> https://cluecon.com
> >>>>
> >>>> FreeSWITCH-users mailing list
> >>>> FreeSWITCH-users at lists.freeswitch.org
> >>>> http://lists.freeswitch.org/mailman/listinfo/freeswitch-users
> >>>> UNSUBSCRIBE:
> >> http://lists.freeswitch.org/mailman/options/freeswitch-users
> >>>> https://freeswitch.com
> >>>
> >>>
> >>>
> _________________________________________________________________________
> >>>
> >>> The FreeSWITCH project is sponsored by SignalWire
> https://signalwire.com
> >>> Enhance your FreeSWITCH install with disruptive priced SMS and PSTN
> >> services.
> >>> Build your next product on our scalable cloud platform.
> >>>
> >>> Join our online community to chat in real time
> >> https://signalwire.community
> >>>
> >>> Professional FreeSWITCH Services
> >>> sales at freeswitch.com
> >>> https://freeswitch.com
> >>>
> >>> Official FreeSWITCH Sites
> >>> https://freeswitch.com/oss
> >>> https://freeswitch.org/confluence
> >>> https://cluecon.com
> >>>
> >>> FreeSWITCH-users mailing list
> >>> FreeSWITCH-users at lists.freeswitch.org
> >>> http://lists.freeswitch.org/mailman/listinfo/freeswitch-users
> >>> UNSUBSCRIBE:
> http://lists.freeswitch.org/mailman/options/freeswitch-users
> >>> https://freeswitch.com
> >>>
> >>
> >>
> >>
> _________________________________________________________________________
> >>
> >> The FreeSWITCH project is sponsored by SignalWire
> https://signalwire.com
> >> Enhance your FreeSWITCH install with disruptive priced SMS and PSTN
> >> services.
> >> Build your next product on our scalable cloud platform.
> >>
> >> Join our online community to chat in real time
> >> https://signalwire.community
> >>
> >> Professional FreeSWITCH Services
> >> sales at freeswitch.com
> >> https://freeswitch.com
> >>
> >> Official FreeSWITCH Sites
> >> https://freeswitch.com/oss
> >> https://freeswitch.org/confluence
> >> https://cluecon.com
> >>
> >> FreeSWITCH-users mailing list
> >> FreeSWITCH-users at lists.freeswitch.org
> >> http://lists.freeswitch.org/mailman/listinfo/freeswitch-users
> >> UNSUBSCRIBE:
> http://lists.freeswitch.org/mailman/options/freeswitch-users
> >> https://freeswitch.com
> >
> >
> > _________________________________________________________________________
> >
> > The FreeSWITCH project is sponsored by SignalWire https://signalwire.com
> > Enhance your FreeSWITCH install with disruptive priced SMS and PSTN
> services.
> > Build your next product on our scalable cloud platform.
> >
> > Join our online community to chat in real time
> https://signalwire.community
> >
> > Professional FreeSWITCH Services
> > sales at freeswitch.com
> > https://freeswitch.com
> >
> > Official FreeSWITCH Sites
> > https://freeswitch.com/oss
> > https://freeswitch.org/confluence
> > https://cluecon.com
> >
> > FreeSWITCH-users mailing list
> > FreeSWITCH-users at lists.freeswitch.org
> > http://lists.freeswitch.org/mailman/listinfo/freeswitch-users
> > UNSUBSCRIBE:http://lists.freeswitch.org/mailman/options/freeswitch-users
> > https://freeswitch.com
> >
>
>
> _________________________________________________________________________
>
> The FreeSWITCH project is sponsored by SignalWire https://signalwire.com
> Enhance your FreeSWITCH install with disruptive priced SMS and PSTN
> services.
> Build your next product on our scalable cloud platform.
>
> Join our online community to chat in real time
> https://signalwire.community
>
> Professional FreeSWITCH Services
> sales at freeswitch.com
> https://freeswitch.com
>
> Official FreeSWITCH Sites
> https://freeswitch.com/oss
> https://freeswitch.org/confluence
> https://cluecon.com
>
> FreeSWITCH-users mailing list
> FreeSWITCH-users at lists.freeswitch.org
> http://lists.freeswitch.org/mailman/listinfo/freeswitch-users
> UNSUBSCRIBE:http://lists.freeswitch.org/mailman/options/freeswitch-users
> https://freeswitch.com
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.freeswitch.org/pipermail/freeswitch-users/attachments/20190624/134b8936/attachment-0001.html>


More information about the FreeSWITCH-users mailing list