Date: Mon, 24 Feb 2003 09:49:10 +0200 From: John Hay <jhay@icomtek.csir.co.za> To: Gregory Bond <gnb@itga.com.au> Cc: stable@FreeBSD.ORG Subject: Re: ntp broadcast mode Message-ID: <20030224074910.GA96888@zibbi.icomtek.csir.co.za> In-Reply-To: <200302240128.MAA29457@lightning.itga.com.au> References: <200302240128.MAA29457@lightning.itga.com.au>
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> Has anyone got NTP broadcast mode working? > > My server has "broadcast x.y.z.255 ttl 4" line. I see the packets at the client > machine with tcpdump. > > 12:28:12.348089 melfw.itga.com.au.ntp > 192.168.71.255.ntp: v4 bcast strat 2 poll 6 prec -28 [tos 0x10] > > I run ntp with "ntp -dddd -n -b -p <pidfile> -f <driftfile>" (with no ntp.conf > file) and I see in the ntp debug that it is reading the broadcast NTP packet. > input_handler: if=1 fd=7 length 48 from c0a847ef 192.168.71.239 > receive: at 241 192.168.71.163<-192.168.71.239 restrict 00 > receive: at 241 192.168.71.163<-192.168.71.239 mode 5 code 5 > But the client never associates with the server. > > "What we have here is a failure to associate!" > > [Both machines are recent 4-Stable, sometime after 4.7R, tho I also fail to > associate with a Solaris client.] > Do you have ntpd setup for crypto? By default ntpd requires that you use some form of crypto (symmetric or autokey) with broadcastclient or its derivatives, multicastclient and manycastserver. If you don't want them to do crypto, you need to add -A to the commandline. Be aware that anybody that can get broadcast packets to your machine, can play with its time then, so think carefully before disabling crypto. John -- John Hay -- John.Hay@icomtek.csir.co.za / jhay@FreeBSD.org To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-stable" in the body of the message
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