Creating an Inbound Call Block List in Call Manager


  • Access to the CUCM Cluster


  • Block a number from calling into the Call Manager system

Creating an Inbound Call Block List – Step by Step

  • Determine which SIP Trunk / Gateway the inbound call comes in on normally
    • Write down the Calling Search Space used for Inbound Calls  (ex: Internal Only)
    • This will be configured on the Gateway or Trunk page (whatever device the calls come in on)
  • Create the following Partitions (Call Routing > Class of Control > Partition)
    • Inbound Calls
    • Filter List
  • Create the following Calling Search Spaces (Call Routing > Class of Control > Calling Search Space)
    • Gateways
    • To_Filter_List
  • Create the following Translation Patterns with the “Inbound Calls” partition
    • Note: The ##XXXX and [^1-9][^1-9]XXXX patterns are for the UCCX CTI ports.  We have to add these as our CTI ports begin at directory number ##7900
    • Ensure that the “Route Next Hop by Calling Party Number” checkbox is checked
    • Ensure that the Calling Search Space is “To_Filter_List”
    • If you do not have UCCX, you only need the blank and ! translation patterns
  • Create the following Translation Patterns with the “Filter List” partition
    • Ensure the Calling Search Space is set to the normal CSS from Step 1 (Internal Only in this example)
    • All three translation patterns are needed
  • Create the following Translation Pattern in the “Filter List Partition”
    • This is the pattern that will block the numbers
    • Ensure that the “Route Option” is set as “Block This Pattern” and “Call Rejected”
    • NOTE: You can simply copy this pattern each time you need to block a new number
    • NOTE: If calls come in with a +1, you may need to add that on this translation pattern in order to match the incoming number
  • Apply the newly created “Gateways” Calling Search Space to the SIP Trunk or Gateway
    • Perform a “Reset” on the gateway or SIP Trunk
    • NOTE:  This is service impacting and will drop calls.  Perform this after hours.
  • Place an inbound call after a few moments and verify inbound calls are still working
  • Block your own number as described in step 6c
  • Place an inbound call and verify it is rejected

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