Got another oddity at the same site as before. This morning, th proxy server appears to have simply stopped processing INVITE requests. It continued to process and log REGISTER requests. The ngrep process I have running to log traffic shows the inbound INVITE request, but nothing after it, no response, no additional INVITE, nothing.
Again, I have ngrep traffic logs for the period if they would help. Although I have not yet increased the debug level on the process. Was hoping something would come of the information I forwarded to serhelp first. However, I'll be increasing the logging level tonight.
Other ideas?