For gatekeeper performance data, we generally recommend that you solicit the help of your Cisco SE because the answer depends to a very large extent on what application the gatekeeper is supporting. That might also explain why there's little customer facing documentation on the subject.
A 3845 gatekeeper with 10 gateway endpoints registered to it and handling 5 calls per second would be under much less stress than one with 10 gateway endpoints registered to it and handling 50 calls per second.
Obviously the number of calls per second is an important factor when determining gatekeeper performance. Also important is the number of concurrent calls.
The guideline for a 3845 is a maximum capacity of 100 Calls per second, and 15000 active calls.
The CCM SRND states the following:
'The choice of gatekeeper platform is based on the number of calls per second and the number of concurrent calls. A higher number of calls per second requires a more powerful CPU, such as a Cisco 3700, 3800, or 7200 Series Router. A higher number of concurrent calls requires more memory. For the latest information on platform selection, contact your Cisco partner or Cisco Systems Engineer (SE).'
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.