Troubleshooting Guide for Cisco Unified Communications Manager, Release 12.5(1) - Cisco Unified Communications Manager System Issues

Publisher

Cisco Systems

URL

https://www.cisco.com/c/en/us/td/docs/voice_ip_comm/cucm/trouble/12_5_1/cucm_b_troubleshooting-guide-1251/cucm_b_troubleshooting-guide-1251_chapter_011.html

Published

unknown

Updated

unknown

Accessed

2026-10-02

HTTP status

200

License

Cisco documentation; all rights reserved; no-redistribution; short excerpts and locators only

Source notes citing this source

• For a CallManager resource interruption, Cisco recommends collecting Cisco CallManager and SDL traces from 15 minutes before to 15 minutes after the interruption, plus perfmon traces; if none exist, start perfmon tracking of per-process CPU and memory. in context
• Cisco's troubleshooting guide says the Cisco CallManager service can stop responding when it lacks resources such as CPU or memory, and that CPU utilisation is generally 100 percent at that time. in context
• When the Cisco CallManager service stops responding, a message stating that the service terminated unexpectedly, with a count of how many times, may appear. in context
• Cisco notes that RAID controller background operations (Consistency Check, Background Initialization, Rebuild, Patrol Read) can significantly affect I/O performance and recommends scheduling Consistency Check and Patrol Read at low load. in context
• Cisco lists a misconfigured LDAP port in the LDAP Authentication window as a possible cause of end-user login timeouts. in context
• Cisco documents that CTI/JTAPI client authentication can fail while Unified CM user login works because OpenLDAP cannot verify the LDAP server certificate; the fix is to use DNS names or set TLS_REQCERT never in /etc/openldap/ldap.conf when IP addresses are used. in context
• Cisco's port guidance for LDAP is 389 without SSL or 636 with SSL for a non-Global Catalog server, and 3268 without SSL or 3269 with SSL for a Global Catalog server. in context
• Cisco says LDAP over SSL problems usually come from invalid, wrong or incomplete certificate chains on Unified CM, and recommends uploading the root and intermediate certificates but not the leaf. in context
• When checking an LDAPS chain, Cisco advises confirming that the root certificate's Issuer and Subject match and that no certificate in the chain has expired. in context

Cite this source record

APA

WarmTransfer. (2026, October 2). Troubleshooting Guide for Cisco Unified Communications Manager, Release 12.5(1) - Cisco Unified Communications Manager System Issues. WarmTransfer. https://warmtransfer.net/knowledge/sources/cisco-cucm-troubleshooting-1251-system-issues

BibTeX

@misc{warmtransfer-cisco-cucm-troubleshooting-1251-system-issues,
  title  = {Troubleshooting Guide for Cisco Unified Communications Manager, Release 12.5(1) - Cisco Unified Communications Manager System Issues},
  author = {{WarmTransfer}},
  year   = {2026},
  url    = {https://warmtransfer.net/knowledge/sources/cisco-cucm-troubleshooting-1251-system-issues},
  note   = {Cisco Systems, accessed 2026-10-02}
}