CUP 7 - CUCM 7 & DNS SRV Config

[jledbett]

Does anyone have the actual configuration examples for enabling DNS SRV in CUCM and CUP 7.x to support high availability?  I have read through all the Cisco docs which seem to be lacking in specific CUCM/CUP configuration examples and which, if any service parameters in CUP need to be changed.

Thanks,

Jeremy.

[Joseph Hardy]

To answer both of your questions...  Yes this functionality is broken, which is why we have a bug filed.

Just getting in to semantics here, but I wouldn't use the words cosmetic nor enhancment to describe the problem.  Cosmetic implies there is no effect beyond what you see, and ehancment typically means we are going to add some functionality to the product.  This is not cosmetic, because selecting the SRV option will change CUCM's behavior.  Specifically, it will query for an SRV record, not an A record.  And if there is no SRV record in DNS it won't work at all.  This is not an enhancment request, because this is a deviation from the designed behavior.  We aren't adding some new functionality, just getting what should be there working.  This is just a bug that needs fixing.

-- Joseph hardy

[srichardson]

Jonathan and Joseph,

Thanks for your supportive answers here.  I have two questions.

1.  The DNS SRV record example is great, but I'm confused.  If I need to also add a DNS SRV record for the Jabber client auto resolution, is this a separate record?  I'm thinking so, but am doing my first install.  If I'm right, then for HA I would want 3 records - one for the Presence Cluster for HA (subject to the BUG), one for the CUCM cluster for resiliency of the Gateway and then one for the Jabber Clients...right?

2. The bug is not fixed yet, is it?  BugTool Kit seems unresolved.  Can you help me with a sample FQDN naming convention for the cluster DNS SRV record and for the Supplemental work around record?

Here is the example from the guide:

DNS SRV Records

You must add a DNS SRV record for the _cuplogin service name in the DNS server on the presence server

domain. If this DNS SRV record does not exist, Cisco Jabber for Windows cannot perform DNS SRV lookups.

The following is an example of a DNS SRV record:

_cuplogin._tcp.company.com

Server: dns_server.company.com

Address: 10.10.1.10

_cuplogin._tcp.company.com SRV service location:

priority =0

weight =0

port =8443

srv hostname =cupserver.company.com

internet address =10.53.56.57

In the preceding example, _cuplogin is the service name. The presence server domain name is company.com.

The SRV record defined in the DNS server for the company.com domain is _cuplogin._tcp.company.com.

Cisco Jabber for Windows 9.1.x Installation and Configuration Guide

38

Plan for Cisco Jabber for Windows

Automatic Server Discovery

Note Cisco Jabber for Windows

• Uses port 8443 by default, not the port that is mapped in the SRV record.

• Supports weight and priority during DNS SRV lookup.