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<DIV><FONT face=Arial size=2>Traffic Flow:</FONT></DIV>
<DIV> </DIV>
<DIV><FONT face=Arial><FONT size=2>External Calls -> PortaBilling / SIP
Gateway (203.10.x.x) -> Cisco SLB Load Balancer (210.15.x.x) -> Either
CCM1 (172.16.55.5) OR CCM2 (172.16.55.6)<SPAN class=699254306-08022008> ->
User Agent</SPAN></FONT></FONT></DIV>
<DIV> </DIV>
<DIV><FONT face=Arial><FONT size=2><SPAN class=699254306-08022008>W</SPAN>hat we
are finding is that the <SPAN class=699254306-08022008>Cisco </SPAN>SLB
(load balancing) is working ok and the packet reaches one of the CCM's - but the
CCM's are discarding the packet because inside the SIP header, the TO: address
does not contain the IP address of the CCM (see <SPAN
class=699254306-08022008>packet </SPAN>capture below taken from the CCM end).
</FONT></FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>> INVITE sip:613xxxxxxxx@210.15.x.x:5060
SIP/2.0<BR>> Via: SIP/2.0/UDP<BR>> 203.10.x.x<BR>>
:5061;branch=z9hG4bK4a2139daf022d80af26275540f1b5722;rport<BR>> Max-Forwards:
70<BR>> From:<BR>>
<sip:0404xxxxxx@203.10.x.x>;tag=171a2a27c0d677b4b142551fa092f0f0<BR>>
To: <sip:613xxxxxxxx@210.15.x.x><BR>> Call-ID: <A
href="mailto:1C6F6260-D46511DC-84E280E4-D0AAFDDC@203.10.x.x">1C6F6260-D46511DC-84E280E4-D0AAFDDC@203.10.x.x</A><BR>>
CSeq: 200 INVITE<BR>> Contact: Anonymous <sip:203.10.x.x:5061><BR>>
Expires: 300<BR>> User-Agent: Sippy</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial><FONT size=2>You can see that once the packet reaches the
CCM, it STILL contains the address of the SLB virtual IP (210.15.x.x) in the SIP
header. Is there a way to change the sip header information in the To: field. We
need 210.15.x.x. rewritten to point to our Cisco Call Manager (172.16.55.5 or
172.16.55.6) so that <SPAN class=699254306-08022008>the packet won't be
discarded and call setup can continue.</SPAN></FONT></FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><SPAN class=699254306-08022008><FONT face=Arial size=2>This is our SLB
config:</FONT></SPAN></DIV>
<DIV><SPAN class=699254306-08022008><FONT face=Arial
size=2></FONT></SPAN> </DIV>
<DIV><SPAN class=699254306-08022008><FONT face=Arial size=2>ip slb serverfarm
CCM-REAL<BR> nat server<BR> predictor leastconns<BR> real
172.16.55.5<BR> inservice<BR> real 172.16.55.6<BR>
inservice<BR>!<BR>ip slb vserver CCM-VIRT-TCP<BR> virtual 210.15.x.x tcp
0<BR> serverfarm CCM-REAL<BR> inservice<BR>!<BR>ip slb vserver
CCM-VIRT-UDP<BR> virtual 210.15.x.x udp 0<BR> serverfarm
CCM-REAL<BR> inservice<BR></FONT></SPAN></DIV>
<DIV> </DIV>
<DIV><FONT face=Arial size=2><BR>Thanks.</FONT></DIV></BODY><!--[object_id=#staff.netspace.net.au#]--><P align=left><FONT face=Arial size=1>This email and any files transmitted with it are confidential and intended solely for the use of the individual or entity to whom they are addressed. Please notify the sender immediately by email if you have received this email by mistake and delete this email from your system. Please note that any views or opinions presented in this email are solely those of the author and do not necessarily represent those of the organisation. Finally, the recipient should check this email and any attachments for the presence of viruses. The organisation accepts no liability for any damage caused by any virus transmitted by this email.</FONT></P></HTML>