SIP to SIP Call Failures on CME to CME - sip-ua conflict/issue?

ccpagel · ‎06-24-2009

Hi,

I have two existing CME systems which I wish to allow internal calls between. These calls will go over an IPSec VPN. However the calls are failing.

Phones DN22xx - London CME 2801 - PIX505 --- Internet ---ASA5505 - India CME 2801 - Phones DN400x

I have configured dial peers on both CME's and the IPSec VPN. I can ping between both systems. The VPN allows traffic between the interface IP's of the CME systems only.

London CME (local SCCP phones 22xx):

interface FastEthernet0/0.100

encapsulation dot1Q 100 native

ip address 10.0.10.250 255.255.255.0

!

voice class codec 101

codec preference 1 g729r8

codec preference 2 g711ulaw

codec preference 3 g711alaw

!

dial-peer voice 25 voip

description *** SIP Peer to India ***

answer-address 400.

destination-pattern 400.

voice-class codec 101

session protocol sipv2

session target ipv4:192.168.15.10

incoming called-number 400.

no vad

India CME (Local SSCP phones 400x):

interface FastEthernet0/0

ip address 192.168.15.10 255.255.255.0

!

voice class codec 100

codec preference 1 g729r8

codec preference 2 g711ulaw

codec preference 3 g711alaw

!

dial-peer voice 10 voip

description *** SIP Peer to London UK ***

answer-address 22..

destination-pattern 22..

voice-class codec 100

session protocol sipv2

session target ipv4:10.0.10.250

incoming called-number 22..

no vad

The CME system at India also has an existing SIP dial peer to a service provider and has sip-ua configured (username, password, realm and registrar).

A call from India (4005) to London (DN2207) fails, the ccsip debug attached. I'm assuming its because the sip-ua configuration is being used for these calls to when I don't want it to be. The from field shows â€œFrom: <sip:4005@201.196.128.56â€ when I need this to be the internal IP 192.168.15.10.

Can anyone offer any assistance with this?

Regards,

Chris

parshah · ‎06-24-2009

Hi,

Can you bind the SIP to the proper interface on both India and London CME.

Looks like there is no bind for media and signalling and so its using the source address of the outbound interface, which is 201.196.128.56

Thanks,

ccpagel · ‎06-24-2009

Hi,

thanks for your input however thats not the problem. 201.196.128.56 isn't an address on the router, it only has one IP and its 192.168.15.10.

The 201.196.128.56 address is the NAT'd address on the firewall. So that when a SIP call is made to the internet with sip-ua the from address is the public IP.

Chris