Luca Bertoncello
2021-Feb-15 07:43 UTC
[asterisk-users] Change by Deutsche Telekom end of februar. Can someone help me?
Hi list! I received a letter from Deutsche Telekom where they say me, that I need to change "something" on my router until 28.02.2021, otherwise I cannot phone anymore. Since I use Asterisk and I don't have a router, I'm not sure what I need to do... In the letter there is an URL to "explain" how to change the configuration if I use a VoIP-phone, but they only say, that I don't have to use Port 5060, but Port 0... Surely there are in this list someone other using Deutsche Telekom... Does someone of them understand what I should change in the Asterisk configuration? Thanks a lot Luca Bertoncello (lucabert at lucabert.de)
Michael Maier
2021-Feb-15 20:40 UTC
[asterisk-users] Change by Deutsche Telekom end of februar. Can someone help me?
Hi! On 15.02.21 at 08:43 Luca Bertoncello wrote:> Hi list! > > I received a letter from Deutsche Telekom where they say me, that I need > to change "something" on my router until 28.02.2021, otherwise I cannot > phone anymore. > Since I use Asterisk and I don't have a router, I'm not sure what I need > to do... > In the letter there is an URL to "explain" how to change the > configuration if I use a VoIP-phone, but they only say, that I don't > have to use Port 5060, but Port 0... > > Surely there are in this list someone other using Deutsche Telekom... > Does someone of them understand what I should change in the Asterisk > configuration?They're switching to DNS NAPTR / SRV[1]. If you are using Asterisk / pjsip and hostnames (tel.t-online.de e.g. for the AllIP service), you won't have any problem (using asterisk 14 or higher), because it's default. But you may have problems with the handling of the calls, because Telekom needs the client always to use the same server for all activities after the register has been done (the SRV entries contain 3 servers and asterisk will use them "randomly" if it detects a problem - regardless which server of the list has been used for registration - this won't work with Telekom and will lead to not working outbound calls / interrupted calls e.g.). This won't happen very often (because they have been extremely stable in the past), but I could see it nevertheless already. If you want to be really sure to not face this problem, you have to create a workaround by adding a rpz zone e.g. with an own bind, which is fed by an own job and presents asterisk just one server when looking up the SRV entries after the NAPTR call. NAPTR / SRV works like this (example for tel.t-online.de): 1. Search for the service names dig noall +answer tel.t-online.de NAPTR tel.t-online.de. 5 IN NAPTR 10 0 "s" "SIPS+D2T" "" _sips._tcp.tel.t-online.de. tel.t-online.de. 5 IN NAPTR 30 0 "s" "SIP+D2T" "" _sip._tcp.tel.t-online.de. 2. Take the answer of the NAPTR output (TCP/TLS, TCP) dig +noall +answer _sips._tcp.tel.t-online.de SRV _sips._tcp.tel.t-online.de. 2234 IN SRV 10 0 5061 s-eps-110.edns.t-ipnet.de. _sips._tcp.tel.t-online.de. 2234 IN SRV 20 0 5061 h2-eps-100.edns.t-ipnet.de. _sips._tcp.tel.t-online.de. 2234 IN SRV 30 0 5061 d-eps-100.edns.t-ipnet.de. dig +noall +answer _sip._tcp.tel.t-online.de SRV _sip._tcp.tel.t-online.de. 3600 IN SRV 30 0 5060 d-epp-100.edns.t-ipnet.de. _sip._tcp.tel.t-online.de. 3600 IN SRV 10 0 5060 s-epp-110.edns.t-ipnet.de. _sip._tcp.tel.t-online.de. 3600 IN SRV 20 0 5060 h2-epp-100.edns.t-ipnet.de. Asterisk now must use always the same server for all activities to Telekom - like register, invite, options - but that's not yet supported by Asterisk - therefore you have to ensure, that asterisk always uses the same server. Easiest way is to provide just one in the DNS answer ... . Regards Michael [1] https://geschaeftskunden.telekom.de/hilfe-und-service/online-services/hilfe-internetanschluss/telefonieanpassung#telekom