Hi Siva,
For PRI utilization alert, here is what you can do login to your CUCM through RTMT and go to System-->Performance
you can see your call manager servers listed here, now choose the one on which your gateway is registered, you will get a big list of parameters here to choose, now click on callsInProgress -->right click on this and now choose an option
Counter instances-->choose your H.323 gateway and now you can see that there will be a graph created with current calls information in RTMT
right-click on the graph now a new tab will get opened called Alert properties, give a description and recommended action and click next, here you can set up a threshold for example if the callsInprogress exceeds certain number it will send you a notification from RTMT to your email.
For monitoring a specific interface (D channel), you might want to use an SNMP monitoring tool and you might want to enable SNMP traps for interface status change.
https://www.cisco.com/c/en/us/support/docs/ip/simple-network-management-protocol-snmp/13506-snmp-traps.html
check for ISDN SNMP traps in this doc, it will give you an idea on how to configure it.
Hope this helps
Thanks!
Jinto.
