On 11/24/2010 11:02 AM, Shaun Ruffell wrote: > On 11/24/2010 10:43 AM, Jonas Kellens wrote: >> The only thing I have is a high level of mentionning of "kernel: dahdi: >> Detected time shift." in /var/log/messages. >> >> >> What is causing this kernel message ? Could this be the cause of the >> server freeze ? >> > > When a system does not have a hardware device installed DAHDI uses the > system time in order to approximate a telephony clock source (what was > previously referred to as dahdi_dummy). Since it uses the system time > to accomplish this, if there is a large gap in the time (typically > because NTP is adjusting the time) DAHDI just reports that it thinks > it's very far behind or ahead of where it should be, and doesn't even > try to "mix" any audio for that interval. > > So, I think the "detected time shift" is more a symptom of something > else causing locks as opposed to the source. > > Is your server keeping accurate wall-time? >
Another case where I regularly see "detected time shift" is when I'm running DAHDI in a virtual machine and go through a suspend / resume cycle. On resume when the system clock is updated DAHDI will notice the shift. -- Shaun Ruffell Digium, Inc. | Linux Kernel Developer 445 Jan Davis Drive NW - Huntsville, AL 35806 - USA Check us out at: www.digium.com & www.asterisk.org -- _____________________________________________________________________ -- Bandwidth and Colocation Provided by http://www.api-digital.com -- New to Asterisk? Join us for a live introductory webinar every Thurs: http://www.asterisk.org/hello asterisk-users mailing list To UNSUBSCRIBE or update options visit: http://lists.digium.com/mailman/listinfo/asterisk-users