c8fa26c0_Internal_Error_Codes___DocWiki__Descriptor
[Code] 21 [Explanation] An outbound dial peer could not be used because the configured maximum number of connections for the dial peer had been reached. [Category] 181 [Descriptor] 
Dial peer connections exceeded
Cisco IOS Voice Troubleshooting and Monitoring -- Cisco VoIP Internal Error Codes - DocWiki
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