NTP Multicast client for 3750

markschnabel · ‎05-05-2009

Can anyone point me where I can find if the 3750 supports the ntp multicast client command?

Marvin Rhoads · ‎05-05-2009

The IOS command reference reports that the command was introduced in 12.1 and is supported in the 12.2 mainline and the 12.2SX train

Software Advisor (http://tools.cisco.com/Support/Fusion/FusionHome.do) doesn't appear to break out that command specifically in the "Features supported in 12.2(50)SE" page, either for IP Base or Advanced IP Services images.

The release notes (http://www.cisco.com/en/US/docs/switches/lan/catalyst3750/software/release/12.2_40_se/release/notes/OL13860.html#wp539899) have several multicast caveats, but ntp multicast client isn't among them.

markschnabel · ‎05-05-2009

I have found the same information, or lack of information. We are running 12.2(46) and the command is there, but do not know if it is supported. I will probably need to open a TAC case to verify.

thanks

thegrave2000 · ‎01-31-2010

Did TAC reply? I'm facing the same issue currently, running 12.2(SE)52 Universal image. Command seems to be there but no NTP packets are transmitted or processed.

rmarosko · ‎06-21-2013

Sorry for resurrecting an old thread, but this still appears to be an issue.

I am discovering this to be the same issue on a 3560X running 15.0(2)SE2. I have confirmed with monitor session that the switch is issuing IGMP report packets for the 224.0.1.1 group in response to IGMP queries from the upstream switch, and I have confirmed that the NTP multicast (224.0.1.1/udp/123) packets are being delivered once from each source every 64 seconds, but the switch steadfastly remains in a "Clock is unsynchronized, stratum 16" state. If I configure the ntp servers, then the bidirectional unicast packets will cause the system to sync up, but that's fairly self-defeating the purpose of being a multicast client.