BAT CSV Generator — Directory Numbers

Bulk provisioning via BAT is the fastest way to add 25+ lines at once, and also the fastest way to pollute a cluster if you skip the three guardrails. First: always run Validate Lines before Insert Lines. Validate checks partition/CSS/voicemail-profile references and rejects the batch if anything's missing, so you catch typos before they land in CUCM. Second: batch at ≤500 lines per CSV. Larger batches take forever to roll back if they go wrong, and BAT's progress indicator becomes unreliable past a few thousand rows. Third: set Calling Party Transform Mask and External Phone Number Mask correctly at creation time — these are the two fields that show up wrong on outbound caller ID after cutover, and fixing 300 lines after the fact is painful.

The External Phone Number Mask is almost always the DID: +1214555XXXX where XXXX is the last 4 of the DN. Using {dn:4} in the tool output tells the generator to substitute the last 4 digits of each DN into the mask. For Calling Party Transform Mask most deployments leave it blank and rely on the CUBE or Route Pattern to set caller ID — but if you're using CUCM-level CLIP/CLIR, set it here.

Voicemail: set Voicemail Profile to the Unity integration profile name (often "Default"). Leaving it blank means DNs have no mailbox, which is fine for common-area phones and bad for users. Forward All / Busy / No Answer destinations typically go to the voicemail pilot, but you may want to leave them blank at creation and let Self-Care Portal users configure them.