Anyone who has deployed Jabber knows of the cisco-uds SRV record that Jabber uses (or Expressway-C in the case of MRA) to discover it’s services. It’s also used for directory searches, and home cluster lookup with ILS.

UDS or User Data Services is a simple REST based API for CUCM. While the UDS API is not as extensive as what you can do with AXL through SOAP and WSDL, it makes a great use case for a front end to allow end users to manage their own devices: Change their single number reach destination, password, speed dials, and conference pins.

For security reasons, most browsers will block an XMLHttpRequest served on one page and originating on another (in the case of a front end making UDS calls to CUCM). To get around this, you would use CORS or Cross Origin Resource Sharing, defining the front end URL inside CUCM.

UDS supports REST queries POST/PUT/GET/DELETE in XML format. Some calls do not require authentication and some do. Ones that do will use Basic authentication built into the browser which encodes the username:password in Base64 format.

UDS resources that do not require authentication
clusterUser, installedLocales, models, options, phoneService(s), servers, timezones, users, version

GET https://{host}:8443/cucm-uds/users?last=Smit
GET https://{host}:8443/cucm-uds/clusterUser?username={userId}

UDS resources that require authentication
credentials, device(s), extension(s), remoteDestination(s), speedDial(s), subscribedService(s), user, userPolicy

POST https:­//{host}:8443/cucm-uds/user/{userId}/speedDials
<!–add speedDials example request body–>

CUCM UDS API Reference
CUCM UDS Developer Guide
CUCM UDS Authentication Guide
Base64 Encoder/Decoder

Unlike other “report this problem” buttons, Jabber’s problem report doesn’t just fly into the cloud somewhere never to be seen again.

It actually contains a lot of useful information about things like: how services are discovered and assigned, what policies are defined, what devices are configured, etc. The problem report can be generated, but is located below:

\Users\AppData\Local\Cisco\Unified Communications\Jabber\CSF\Logs\csf-unified.log

One of the biggest questions I get is where configurations exist, and what takes priority ? Before looking at the file, I would have guessed 3 places, but as you can see below its actually 12!

1: TftpOverrideConfigStore [10] jabber-config.xml
2: LocalFileConfigStore [20] AppData\Roaming\Cisco\Unified Communications\Jabber\CSF\Config\jabberLocalConfig.xml
3: Ucm90ConfigStore [25]
4: PresenceAuthenticatorStore [28]
5: ServiceDiscoveryConfigStore [29]
6: PresenceConfigStore [30] Presence Server TFTP+CCMCIP Settings
7: RegistryConfigStore [31] HKCU\Software\Cisco Systems, Inc.\JabberWerxCpp
8: PresenceProductModeStore [35]
9: UrlProvisioningConfigStore [499]
10: BootstrapConfigStore [500] ProgramData\Cisco Systems\Cisco Jabber\
11: InMemoryConfigStore [600]
12: jabber-config-defaults.xml [2147483647] Program Files (x86)\Cisco Systems\Cisco Jabber\jabber-config-defaults.xml

Each of these stores contain configuration elements in the form of <tags>, retrieved from either the local machine, or through HTTP GET requests

When Jabber is launched, Jabber first tries to read jabberLocalConfig.xml for cached settings, if any exists. It then attempts to reach the domain controller of the machine you are running on for SSO. If both of those fail, only then will it give you a login prompt. If no cached username is found, email is prompted for and DISCOVERY begins.

retrieve email address and parse domain:

Getting LastLoggedInUserName from ConfigFeatureSet
Getting servicesDomain from ConfigFeatureSet
Getting PresenceDomain from ConfigFeatureSet
ServicesDomain key not found, parsing email address.
Retrieved Email Address
Retrieved DNS Domain ‘’ from ‘Email Address from UserInput’
Domain is set to:

check for webex im:

makeCasLookupForDomain result is ‘Code: NOT_WEBEX_CUSTOMER; CasUrl:;

check SRV records for on-prem and mra:

*—–* DNS query has succeeded.
*—–* DNS query has failed: DNS name does not exist.

determine home cluster:

*—–* Making HTTP request to:

fetch user data:

set location:

setCurrentLocationOption start: description: Jeffs House ,id: fff8ffb0-1332-4da7-ba78-647b35aa25b2
IsGatewayAddressSubnetExists: gateway address: 00::50::56::E3::E5::50, subnet:, locations: 1