On an ATA 190 in CCMAdmin on CUCM 9.1(2)SU2, under the Product Specific part of the device configuration, there's a parameter called "Modem Line". I can't find any mention of this in the ATA manual, and the CCMAdmin help page has no mention either.
Are you getting this error “Installer User Interface Mode Not Supported. The installer cannot run in this UI mode. To specify the interface mode, use the -i command-line option, followed by the UI mode identifier. The value UI mode identifiers...
The below trick might come handy when you have to add a new node to a cluster but you don't have or is unsure of the security password for the publisher. This procedure has been around for ages.
1) Login into the CLI of the Publisher.