Unified CM call throttling automatically throttles or denies new call attempts when conditions would cause excessive delay between going off hook and receiving dial tone; in that state the system is in Code Yellow.
Checked 2026-10-02
When throttling is necessary to prevent excessive delay to dialtone, the system enters a Code Yellow state and new call attempts are throttled (denied).
- Vendor
- Cisco
- Product
- Cisco Unified Communications Manager
- Subsystem
- call throttling
- Deployment
- on-premises
- Region
- not restricted
- Release range
- 15 and SUs as of 2026-10-02
- Checked
- 2026-10-02
Sources
- Feature Configuration Guide for Cisco Unified Communications Manager, Release 15 and SUs - Configure Call Throttling — Cisco Systems · tier 2 current vendor documentation · Configure Call Throttling > Call Throttling Overview
Cite this note
APA
WarmTransfer. (2026, October 2). Troubleshooting high CPU and service crashes in Unified CM: source note cucm-high-cpu-troubleshooting-throttling-denies-new-calls. WarmTransfer. https://warmtransfer.net/knowledge/claims/cucm-high-cpu-troubleshooting-throttling-denies-new-calls
BibTeX
@misc{warmtransfer-claim-cucm-high-cpu-troubleshooting-throttling-denies-new-calls,
title = {Troubleshooting high CPU and service crashes in Unified CM: source note cucm-high-cpu-troubleshooting-throttling-denies-new-calls},
author = {{WarmTransfer}},
year = {2026},
url = {https://warmtransfer.net/knowledge/claims/cucm-high-cpu-troubleshooting-throttling-denies-new-calls},
note = {Source note cucm-high-cpu-troubleshooting-throttling-denies-new-calls, checked 2026-10-02}
}