[cisco-voip] Is there a way to rewrite SIP headers?
Andy Saykao
andy.saykao at staff.netspace.net.au
Fri Feb 8 01:48:57 EST 2008
Traffic Flow:
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) -> User Agent
What we are finding is that the Cisco 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 packet capture below taken from
the CCM end).
> INVITE sip:613xxxxxxxx at 210.15.x.x:5060 SIP/2.0
> Via: SIP/2.0/UDP
> 203.10.x.x
> :5061;branch=z9hG4bK4a2139daf022d80af26275540f1b5722;rport
> Max-Forwards: 70
> From:
> <sip:0404xxxxxx at 203.10.x.x>;tag=171a2a27c0d677b4b142551fa092f0f0
> To: <sip:613xxxxxxxx at 210.15.x.x>
> Call-ID: 1C6F6260-D46511DC-84E280E4-D0AAFDDC at 203.10.x.x
> CSeq: 200 INVITE
> Contact: Anonymous <sip:203.10.x.x:5061>
> Expires: 300
> User-Agent: Sippy
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 the packet won't be discarded and call setup can
continue.
This is our SLB config:
ip slb serverfarm CCM-REAL
nat server
predictor leastconns
real 172.16.55.5
inservice
real 172.16.55.6
inservice
!
ip slb vserver CCM-VIRT-TCP
virtual 210.15.x.x tcp 0
serverfarm CCM-REAL
inservice
!
ip slb vserver CCM-VIRT-UDP
virtual 210.15.x.x udp 0
serverfarm CCM-REAL
inservice
Thanks.
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.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: https://puck.nether.net/pipermail/cisco-voip/attachments/20080208/b72d4c0a/attachment.html
More information about the cisco-voip
mailing list