Can't register sip on provider

[Sergiy Shamshurin]

Hi, the problem is sip is not registering.

i have cisco ISR4321/K9 

Cisco IOS Software, ISR Software (X86_64_LINUX_IOSD-UNIVERSALK9-M), Version 15.4(3)S7, RELEASE SOFTWARE (fc3)

show run:

voice service voip
 ip address trusted list
  ipv4 212.34.224.205          -   (it's provider outbound proxy ip)
  allow-connections sip to sip
 sip      
  outbound-proxy dns:extus.ims.ucom.am    - (dns is resolvable, it is parameters from provider)

sip-ua    
 credentials username ****** password ******* realm ims.ucom.am
 authentication username ****** password ****** realm ims.ucom.am
 registrar dns:ims.ucom.am expires 60
 sip-server dns:ims.ucom.am
 connection-reuse

____________________________________________

realm and registrar  'ims.ucom.am' - it is parameters from provider (registrations go through outbound proxy)

i also try with 'no  connection-reuse' - no changes

321#sho sip-ua register stat
Line                             peer       expires(sec) reg survival P-Associ-URI
================================ ========== ============ === ======== ============
(number***)                      -1         24           no  normal 

The strange thing is that from debug ccsip all i see that cisco sent register messages to provider but don't see any answer from provider, no any 'unauthorized' messages. and in the end i see 'out of retries' error. But if i collect 'monitor capture' from interface i see that provider send 'unauthorized' messages with

WWW-Authenticate: Digest realm="ims.ucom.am",nonce="4EB63020254CD25900000000AD521679",algorithm=MD5,qop="auth"

but cisco don't reply on this and strangly don't show it in sip debugs.

I try to register with x-lite (soft client) with same parameters and it's worked, and in capture i see that x-lite send same register packet as cisco, then recieve same 'unauthorized' message from provider and then again send register but with authentication and 'nounce' from provider message, then it register and all worked.

So the question is what the problem with cisco registering? Why i don't see 'unauthorized' messages in debug ccsip all? and why it's cannot register? Please help.

[Jonathan Unger]

Hi Sergiy,

A few points:

1. Have you tried reloading the router?
   • In my experience the ISR4K's have many more bugs than the ISRG2's, and sometimes you get lucky with a reload.
2. Is the unauthorized message that you can see in the PCAP but not in the SIP trace coming from the provider IP address that you would expect? Or somewhere different?
3. Are you using zone based firewall on your ISR?

[Sergiy Shamshurin]

Hi Jonathan,

Tanks for reply.

1. I don't try to reload but i'm planning this today maybe(it in production)

2. Yes, it's coming from correct ip that i expected.

3. No, no zone-based firewalls, just access lists but i check it and they not blocking anything relative to this problem.

[Sergiy Shamshurin]

Hi, again.

I try reload, but problem still the same.

then i update ios to last recomended version by cisco it's now

Cisco IOS XE Software, Version 03.16.06.S - Extended Support Release
Cisco IOS Software, ISR Software (X86_64_LINUX_IOSD-UNIVERSALK9-M), Version 15.5(3)S6, RELEASE SOFTWARE (fc3)

isr4300-universalk9.03.16.06.S.155-3.S6-ext.SPA.bin

and still nothing, same symptoms.

So maybe someone have some else recommendations?

[Sergiy Shamshurin · Accepted solution]

The problem was with NAT, on outside interface we have

           ip nat outside

so we need to configure

       voice service voip

           sip

               bind all source-interface "name of the internal interface"

after that sip registered successfully

[Jonathan Unger]

Thank you for following up with your solution!