Date: Fri, 25 Oct 2002 12:05:26 -0700 From: Steve Francis <steve@expertcity.com> To: Romain Kang <romain@kzsu.stanford.edu> Cc: freebsd-net@FreeBSD.ORG Subject: Re: post-ifconfig delay causes ntpdate failure? Message-ID: <3DB995F6.90506@expertcity.com> References: <20021025190027.GA45509@kzsu.stanford.edu>
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Um.. Seems like its the switch port Spanning tree bringing the port active after 15 seconds of learning and 15 seconds of listening? Romain Kang wrote: >I spent some time trying to figure out why the my ntpdate doesn't >seem to work. It appears to me that the fxp0 isn't transmitting >for a relatively long period of time following the ifconfig. The >saga follows. > >On the client (10.10.1.101), I gave ntpdate the -d flag and saved >its output. ntpdate claimed that the server (10.10.1.100) never >replied to its ntp queries. > >I stuck a tcpdump into rc.network, then ran a ping loop to see how >long it took before the first ping to the server succeeded. The >shell code claimed 25 seconds: > (T0=`date +%s` > I=0 > MAX=30 > echo "rc.network: first ping test" > while ! { ping -q -c1 10.10.1.100 > /dev/null; } > do > I=`expr $I + 1` > test $I -ge $MAX && break > sleep 1 > done > T1=`date +%s` > DIFF=`expr $T1 - $T0` > echo "$DIFF seconds to first successful ping") >> $LOG 2>&1 > >tcpdump on the client saw: > >23:55:53.019046 arp who-has 10.10.1.100 (2e:2f:30:31:32:33) tell 10.10.1.101 >23:56:05.219283 arp who-has 10.10.1.100 (2e:2f:30:31:32:33) tell 10.10.1.101 >23:56:05.220140 arp reply 10.10.1.100 is-at 0:90:fb:8:71:fd >23:56:05.220172 10.10.1.101 > 10.10.1.100: icmp: echo request >23:56:05.221017 10.10.1.100 > 10.10.1.101: icmp: echo reply > >The server saw: > >23:56:05.967915 arp who-has 10.10.1.100 (2e:2f:30:31:32:33) tell 10.10.1.101 >23:56:05.967950 arp reply 10.10.1.100 is-at 0:90:fb:8:71:fd >23:56:05.969464 10.10.1.101 > 10.10.1.100: icmp: echo request >23:56:05.969513 10.10.1.100 > 10.10.1.101: icmp: echo reply > >With the ping loop inserted before ntpdate, the client was able to >get its initial date set. This works, but it seems like a crude hack. >Anyone have a better idea? >-- >Romain Kang Disclaimer: I speak for myself alone, >romain@kzsu.stanford.edu except when indicated otherwise. > >To Unsubscribe: send mail to majordomo@FreeBSD.org >with "unsubscribe freebsd-net" in the body of the message > > To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-net" in the body of the message
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