For phone unregistration issues we can start by looking at the phone console logs. However, a parallel packet capture from the IP phone and CUCM ( to which the phone is registered ) is what would really help in nailing the issue. Phone in unregistered state means it has got the IP address, it may be getting unregistered due to network issues like SCCP or TFTP ports being blocked or due to some other routing / firewall issues.
IntroductionCUCM Routing RulesDial String implementation PolicyCUCM Routing LogicSIP URI Call Routing Analysis+++ Case Study: 1 ++++++ Case Study: 2 +++Conclusion
Over the last few months, I have had the privilege of working on SI...
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...