Calling between Cisco CUCM PBX and Webex

[Pavan Manjunath]

I need to establish a call between Cisco CUCM PBX and Webex. We have below infrastructure with us

on-premises 2 CUBE/ISR

ISR1: Cisco 2200 (Cisco CME is configured and running)

ISR2: Cisco 4400 (PSTN is configured and running)

Cisco Unified CM Administrator: v12.0.1 (licensed), v14.0 & v15.0(Evaluation mode)

Webex (Enterprise trail subscription)

With the above infrastructure, I need to configure Cisco to Webex setup. 

Need configuration details to achieve the scenario.

Thanks,

Pavan

[Pavan Manjunath]

@Roger Kallberg 

Challenges with ISR 4400 Routers:

1. ISR 4400 Router with Voice Card:

   • The existing PSTN is configured and operational.

   • To proceed with the Cisco to Webex setup, the router requires a valid CA certificate, which is mandatory from Webex.

   • The router fails to generate the CSR with 2048-bits, even after using the command crypto key generate rsa general-keys label cme-4400-webex-key modulus 2048 exportable and creating a trust point.

   • The certificate being generated is less than 1024-bits, whereas the minimum requirement is 1024-bits.

   • Assistance is needed to generate the required certificate.

2. ISR 4400 Router without Voice Card:

   • Due to the failure in generating certificates from the first router, the IT team attempted to generate the certificates on a second ISR 4400 router.

   • The CSR generation worked on the second router, and the IT team purchased and installed a trial SSL certificate.

   • However, this router does not have a voice card. Is voice card required for Cisco to Webex setup or cisco to webex calling?

Request for Assistance and advise: We need your help to resolve the challenges we are facing with these two ISR 4400 routers.
Thanks,

[Roger Kallberg]

What version of IOS do you run on the ISR4Ks and what are they licensed for?

You don’t need a voice card for setting up a router as a LGW for Webex Calling.

[Pavan Manjunath]

Thanks for your reply @Roger Kallberg 
verison of IOS: Cisco IOS XE Software, Version 17.12.04

License Details:

#show license all
Smart Licensing Status
======================

Smart Licensing is ENABLED

License Conversion:
Automatic Conversion Enabled: True
Status: Not started

Export Authorization Key:
Features Authorized:
<none>

Utility:
Status: DISABLED

Smart Licensing Using Policy:
Status: ENABLED

Account Information:
Smart Account: <none>
Virtual Account: <none>

Data Privacy:
Sending Hostname: yes
Callhome hostname privacy: DISABLED
Smart Licensing hostname privacy: DISABLED
Version privacy: DISABLED

Transport:
Type: cslu
Cslu address: <empty>
Proxy:
Not Configured
VRF: <empty>

Miscellaneous:
Custom Id: <empty>

Policy:
Policy in use: Merged from multiple sources.
Reporting ACK required: yes (CISCO default)
Unenforced/Non-Export Perpetual Attributes:
First report requirement (days): 365 (CISCO default)
Reporting frequency (days): 0 (CISCO default)
Report on change (days): 90 (CISCO default)
Unenforced/Non-Export Subscription Attributes:
First report requirement (days): 90 (CISCO default)
Reporting frequency (days): 90 (CISCO default)
Report on change (days): 90 (CISCO default)
Enforced (Perpetual/Subscription) License Attributes:
First report requirement (days): 0 (CISCO default)
Reporting frequency (days): 0 (CISCO default)
Report on change (days): 0 (CISCO default)
Export (Perpetual/Subscription) License Attributes:
First report requirement (days): 0 (CISCO default)
Reporting frequency (days): 0 (CISCO default)
Report on change (days): 0 (CISCO default)

Usage Reporting:
Last ACK received: <none>
Next ACK deadline: Feb 11 11:11:39 2024 IST
Reporting push interval: 30 days
Next ACK push check: <none>
Next report push: Jan 17 15:47:31 2025 IST
Last report push: <none>
Last report file write: <none>

Trust Code Installed: <none>

License Usage
=============

securityk9 (ISR_4400_Security):
Description: securityk9
Count: 1
Version: 1.0
Status: IN USE
Export status: NOT RESTRICTED
Feature Name: securityk9
Feature Description: securityk9
Enforcement type: NOT ENFORCED
License type: Perpetual

[Pavan Manjunath]

As per webex doc: https://help.webex.com/en-us/article/jr1i3r/Configure-Local-Gateway-on-Cisco-IOS-XE-for-Webex-Calling#id_100573

sip-ua
 timers connection establish tls 5
 transport tcp tls v1.2
 crypto signaling default trustpoint EmptyTP cn-san-validate server
 tcp-retry 1000

Enter the following commands to configure CUBE as a Webex Calling Local Gateway:

 
voice service voip
 ip address trusted list
  ipv4 x.x.x.x y.y.y.y
 mode border-element
 media statistics

sip/sip-ua & voice service voipis not working -> throwing below error
% Invalid input detected at '^' marker.

The router does not have a voice card for Webex Calling. Is a voice card mandatory on a Cisco device for configuring and utilizing SIP functionalities like sip-ua for webex calling?

[Roger Kallberg]

As I responded earlier you do not need a voice card to setup a LGW. However you do need to have the router licensed for voice services. From what I can tell by your shared information you have it licensed for security services, but not voice. Fix that to get the commands required as outlined in the LGW configuration guide.

[Pavan Manjunath]

@Roger Kallberg Thank you. We will proceed with licensing the router for voice services.

[John Steele]

@Pavan Manjunath everything is in the link that @dtibbe provided to you.  Open up the individual bookmarks, start from the top and work your way down.

[dtibbe]

Have you checked https://help.webex.com/jr1i3r/? There are many scenarios explained including Webex/UCM/LGW configurations

[Pavan Manjunath]

Thanks @dtibbe for your reply. Yes, I have checked https://help.webex.com/jr1i3r/? and trying to configure.

Currently, we have Cisco 4400 Series router and it has Cisco IOS XE Software, Version 16.09.02 with an existing PSTN gateway running. 

Now, we have to use the same Cisco 4400 router to create an another Local Gateway function for Webex Calling. Could you please guide me on how to proceed?

[Roger Kallberg]

Let’s start by clarifying that having PSTN services setup in a Cisco router isn’t the same as a Webex Local Gateway. Webex Local Gateway is a way to integrate your on-premises CM with Webex Calling and can also be used for providing PSTN services to Webex Calling. Based on what you asked me in PM, you don’t need to be on 17.12, but 16.09.02 is very old and would likely need to be updated to something more current, like 17.09.04 for example. You can absolutely have PSTN services and Local Gateway services setup on the same router. It all comes down to your ability to handle dial peer configuration.

[Pavan Manjunath]

Thanks @Roger Kallberg The reply helped me to proceed further.