Does anyone know if Cisco SLB can support the SIP protocol? We have a
situation where we need to forward external calls from our SIP gateway
to our Cisco Call Manager 5.1 servers. This is because our SIP gateway
isn't smart enough to distinguish if one of the CCM is down and try the
other one - instead it forwards both calls to the CCM and we get
presented with two calls on our IP phones. We can set the SIP gateway to
forward it to one CCM, but this wouldn't give us any redundancy or fail
over should one CCM fail.
Here's the 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
I'm finding that the SIP headers do not have any of CCM IP's in them
(172.16.55.5 or 172.16.55.6) so obviously the packet gets discarded when
it hits the CCM. Instead the SIP header has the FROM: address as the SIP
gateway IP (203.10.x.x) and the TO: address as the virtual server IP
(210.15.x.x) (which we've set the SIP gateway to forward to) - is there
anyway to have TO address changed to 172.16.55.5/6 so the SIP call hits
the SLB and then is load balanced to one of the CCM's???
> INVITE sip:987654321@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:12345678@203.10.x.x>;tag=171a2a27c0d677b4b142551fa092f0f0
> To: <sip:987654321@210.15.x.x>
> Call-ID: 1C6F6260-D46511DC-84E280E4-D0AAFDDC@203.10.x.x
<mailto:1C6F6260-D46511DC-84E280E4-D0AAFDDC@203.10.x.x>
> CSeq: 200 INVITE
> Contact: Anonymous <sip:203.10.x.x:5061>
> Expires: 300
> User-Agent: Sippy
> cisco-GUID: 1494077719-3576435164-2575237145-3119402593
> h323-conf-id: 1494077719-3576435164-2575237145-3119402593
> Content-disposition: session
> Content-Length: 420
> Content-Type: application/sdp
Thanks.
Andy
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situation where we need to forward external calls from our SIP gateway
to our Cisco Call Manager 5.1 servers. This is because our SIP gateway
isn't smart enough to distinguish if one of the CCM is down and try the
other one - instead it forwards both calls to the CCM and we get
presented with two calls on our IP phones. We can set the SIP gateway to
forward it to one CCM, but this wouldn't give us any redundancy or fail
over should one CCM fail.
Here's the 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
I'm finding that the SIP headers do not have any of CCM IP's in them
(172.16.55.5 or 172.16.55.6) so obviously the packet gets discarded when
it hits the CCM. Instead the SIP header has the FROM: address as the SIP
gateway IP (203.10.x.x) and the TO: address as the virtual server IP
(210.15.x.x) (which we've set the SIP gateway to forward to) - is there
anyway to have TO address changed to 172.16.55.5/6 so the SIP call hits
the SLB and then is load balanced to one of the CCM's???
> INVITE sip:987654321@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:12345678@203.10.x.x>;tag=171a2a27c0d677b4b142551fa092f0f0
> To: <sip:987654321@210.15.x.x>
> Call-ID: 1C6F6260-D46511DC-84E280E4-D0AAFDDC@203.10.x.x
<mailto:1C6F6260-D46511DC-84E280E4-D0AAFDDC@203.10.x.x>
> CSeq: 200 INVITE
> Contact: Anonymous <sip:203.10.x.x:5061>
> Expires: 300
> User-Agent: Sippy
> cisco-GUID: 1494077719-3576435164-2575237145-3119402593
> h323-conf-id: 1494077719-3576435164-2575237145-3119402593
> Content-disposition: session
> Content-Length: 420
> Content-Type: application/sdp
Thanks.
Andy
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.