Hi, I set up OpenSBC on Vyatta firewall regarding the doc of "Install OpenSBC on Vyatta Firewall" by Michael W. Picher.

The Vyatta firewall and OpenSBC (B2BUpperReg Mode) are running well now. I have two sip clients both registered successfully to SIPX through OpenSBC/Vyatta. When I made call between these two sip clients, the call was shown established but no audio comes out. While when I configured these two sip clients bypassed OpenSBC and registered to SIPX directly through Vyatta firewall, they can make call to each other.

The following is my OpenSBC configuration file. My SIPX server IP is 192.168.2.4 and my OSBC&Vyatta IP is 192.168.2.1.
[Solegy]
RTTS-Client-Address=0.0.0.0

[OpenSBC HTTP Admin]
HTTP User=admin
HTTP Password=XXXXXXXXXXX
SMTP Return Address=noreply@localhost
SMTP Password=KlbLD2axRCk=
SMTP Server=localhost

[OpenSBC-General-Parameters]
SIP-Log-Level=5
PTRACE-Log-Level=1
Log-File-Prefix=b2bua
User-Agent-Name=sbc.sipx.net
SBC-Application-Mode=B2BUpperReg Mode
Enable-Trunk-Port=True
Enable-Calea-Port=True
RTP-Min-Port=10000
RTP-Max-Port=65535
NAT-Keep-Alive-Interval=15
Send-OPTIONS-NAT-Keep-Alive=True
Send-Responses-Using-New-Socket=True
Enable-Local-Refer=False
Disable-Refer-Optimization=False
Max-Forwards=70
Encryption-Mode=XOR
Encryption-Key=GS
Alerting-Timeout=30000
Seize-Timeout=60000
SIP-Timer-B=Default
SIP-Timer-H=Default
Session-Keep-Alive=1800
Session-Max-Life-Span=10800
Max-Concurrent-Session=100
Max-Call-Rate-Per-Second=10

[RTP-Proxy]
Proxy-On-Private-Contact=True
Proxy-On-via-received-vs-signaling-address=True
Proxy-On-Private-Via=True
Proxy-On-Different-RPORT=True
Proxy-All-Media=True

[B2BUA-Routes]
Enable-Route-Scripting=False
Route-Script=b2bua-route.cscript
Route-List Array Size=1
Route-List 1=[sip:*@sipx.net:*] sip:192.168.2.4:5060
Insert-Route-Header=True
Rewrite-TO-URI=True
Prepend-ISUP-OLI=False
Route-By-Request-URI=True
Route-By-To-URI=False
Drop-Routes-On-Ping-Timeout=False
Use-External-XML=False
External-XML-File=b2bua-route.xml

[Internal-DNS-Mapping]
Internal-DNS-Map Array Size=1
Internal-DNS-Map 1=[sip:sipx.net] sip:192.168.2.4:5060

[Upper-Registration]
All-Reg-As-Upper-Reg=False
Enable-Stateful-Reg=False
Rewrite-TO-Domain=True
Rewrite-FROM-Domain=True
Route-List Array Size=1
Route-List 1=[sip:sipx.net] sip:192.168.2.4:5060

[Local-Domain-Accounts]
Accept-All-Registration=True
Account-List Array Size=0

[Media-Server]
Enable-Media-Server=False
Media-Server-Number=5000
Codec-List Array Size=0
No-RTP-Proxy-On-All-Transfers=False
Enable-Announcement-Service=False
4xx-Error-Map=prompts/basic/cant_complete.wav
5xx-Error-Map=prompts/basic/cant_complete.wav
6xx-Error-Map=prompts/basic/cant_complete.wav
Announcement-Error-Map Array Size=0