[Users] Route-header DNS lookup?
norm at goes.com
Thu Jul 6 14:57:25 CEST 2006
Perhaps there needs to be SRV records in the DNS server that manages
Below are example SRV records. If this is your first time working with
SRV records, I strongly suggest reading some of the online doc that
deals with them.
_sip._tcp.iptel1.ipatl.se. IN SRV 0 0 5060 sip.iptel1.ipatl.se.
_sip._udp.iptel1.ipatl.se. IN SRV 0 0 5060 sip.iptel1.ipatl.se.
Kerker Staffan wrote:
> i recently bounced into this problem, and i'm not sure here.
> i'm running the openser-devel, with the cacheless db_mode=3. (works fine btw)
> the record-route header received by the proxy on the other side (SNOM4S), inserts
> the domain name (iptel1.ipatl.se) and not the hostname (sip.iptel1.ipatl.se) in the
> record-route header, and uses the maddr=<ip_of_server> with the actual server IP address.
> now, when my client (behind the OpenSER) replies with an ACK to the incomming OK,
> it uses the Route-header recieved in the RR-header, and sends the ACK to OpenSER. i
> then get the following errors in OpenSER.
> /usr/local/sbin/openser: ERROR: mk_proxy: could not resolve hostname: "iptel1.ipatl.se"
> /usr/local/sbin/openser: ERROR: uri2proxy: bad host name in URI <sip:4ffec4ce755c218a72228c6643cb3b6b at iptel1.ipatl.se:5060;maddr=172.28.248.66;transport=udp;lr>
> the ACK i sent look like this:
> Request-Line: ACK sip:2307 at iptel1.ipatl.se;gruu=6fg9n6dl SIP/2.0
> Via: SIP/2.0/UDP 172.28.248.52:2051;branch=z9hG4bK-d96b1fvapkyn;rport
> Route: <sip:172.28.248.10;lr=on;ftag=li9buf1i4p>
> Route: <sip:4ffec4ce755c218a72228c6643cb3b6b at iptel1.ipatl.se:5060;maddr= 172.28.248.66;transport=udp;lr>
> From: "Snom 2652" <sip:2652 at ipatl.se>;tag=li9buf1i4p
> To: <sip:2307 at ipatl.se>;tag=hvseiz7kgb
> Call-ID: 3c269d83900b-xj3ild14y880 at snom360
> CSeq: 1 ACK
> Max-Forwards: 70
> Contact: <sip:2652 at 172.28.248.52:2051;line=cp4a7ljd>
> Content-Length: 0
> as far as i understand, according the rfc 3263, the route-header may contain domain name that
> has to be resolved using SRV.
> "6 Constructing SIP URIs
> In many cases, an element needs to construct a SIP URI for inclusion
> in a Contact header in a REGISTER, or in a Record-Route header in an
> INVITE. According to RFC 3261 , these URIs have to have the
> property that they resolve to the specific element that inserted
> them. However, if they are constructed with just an IP address, for
> then should the element fail, there is no way to route the request or
> response through a backup.
> SRV provides a way to fix this. Instead of using an IP address, a
> domain name that resolves to an SRV record can be used:
> now, OpenSER only asks DNS for an A record of the name recieved in the route header,
> and since that's a domain name, it's unresolvable, and so the ACK is never sent.
> any hints or clues?
> best regards,
> /Staffan Kerker
> Staffan Kerker
> Saab Communications, Växjö
> p. +46 470 42185
> c. +46 705 391365
> m. staffan.kerker at saabgroup.com
> Users mailing list
> Users at openser.org
More information about the Users