On 4/22/07, Nigel Henry <cave.dnb@xxxxxxxxxx> wrote:
On Sunday 22 April 2007 22:48, Kam Leo wrote:
> On 4/22/07, Nigel Henry <cave.dnb@xxxxxxxxxx> wrote:
> > On Sunday 22 April 2007 22:14, Kam Leo wrote:
> > > On 4/22/07, Nigel Henry <cave.dnb@xxxxxxxxxx> wrote:
> > > > On Sunday 22 April 2007 19:16, Steve Siegfried wrote:
> > > > > Nigel Henry wrote:
> > > > > > On Sunday 22 April 2007 18:19, Scott Berry wrote:
> > > > > > > Nigel, what would you want to ping? I think you could put a
> > > > > > > line in that script to do that.
> > > > > > >
> > > > > > > Scott
> > > > > >
> > > > > > Pinging a server on the Internet isn't really the problem, as
> > > > > > long as nobody get's T'd off on getting a ping on a daily basis.
> > > > > > All I want is a script that will continually send a ping to <some
> > > > > > server>, then when the Internet connection is up, and it gets a
> > > > > > positive response from the server, will then run
> > > > > > /usr/local/bin/ntp-restart, and terminate the ping. This will
> > > > > > then restart the ntp daemon, and all of the servers listed in
> > > > > > /etc/ntp.conf will be polled.
> > > > > >
> > > > > > At the moment when the ntp daemon is started at bootup on FC2, I
> > > > > > get varying results. Post bootup I connect to the Internet, and
> > > > > > sometimes just one of the six timeservers is listed when running
> > > > > > ntpq> pe, and sometimes 4 of the timeservers are listed, but
> > > > > > never the 6. If I do an /etc/init.d/ntpd stop, followed by an
> > > > > > /etc/init.d start, then run ntpq, I see all 6 Internet
> > > > > > timeservers listed.
> > > > > >
> > > > > > There is a problem with the ntp daemon, at least on FC2, when no
> > > > > > Internet connection is available at bootup.
> > > > > >
> > > > > > Nigel.
> > > > >
> > > > > You can probably do this without pinging.
> > > > >
> > > > > Assuming you talk to the outside internet via eth0, then "ifconfig
> > > > > eth0" won't tell you what your ip-address is until eth0 is all the
> > > > > way up.
> > > > >
> > > > > Thus, the following script will either:
> > > > > - print your ip-address and return 0 (success),
> > > > > or
> > > > > - print "eth0 not active." and return 1 (failure).
> > > > >
> > > > > > #!/bin/ksh
> > > > > > DEVICE=${1:-eth0}
> > > > > > if [ `/sbin/ifconfig | grep ^$DEVICE | wc -l` = 0 ]
> > > > > > then echo "$DEVICE not active."
> > > > > > exit 1
> > > > > > else mungeline=`/sbin/ifconfig $DEVICE | grep "inet addr" |
> > > > > > tr -s ":" " " | cut -d' ' -f4` echo $mungeline
> > > > > > exit 0
> > > > > > fi
> > > > >
> > > > > Hope this helps,
> > > > >
> > > > > -S
> > > >
> > > > This is my setup. I have 2 machines on a LAN. These access the
> > > > Internet through a Smoothwall firewall, which is installed on an old
> > > > machine. The Smoothwall accesses the Internet through a serial modem.
> > > > To connect to Internet I have to have one of the machines on the LAN
> > > > booted up, so as access the web interface to the Smoothwall.
> > > >
> > > > So this is the way it goes. The Smoothwall is left running
> > > > continually, but I shut down the dialup connection, and the 2
> > > > machines on the LAN last thing at night, unless I'm doing updates.
> > > >
> > > > Next day. Smoothwall is still running, but no connection to the
> > > > Internet. Next I boot the machine on the LAN that has the Internet
> > > > timeservers listed in /etc/ntp.conf. The machine boots up (this is
> > > > FC2) , but because no Internet connection is available the ntpd times
> > > > out, goes out to lunch, gives up trying to contact the timeservers,
> > > > whatever. Post boot up, and running ntpq> pe, sometimes there is 1 of
> > > > the 6 timeservers showing, and sometimes 4 of the 6.
> > > >
> > > > If I now stop and start ntpd all 6 of the timeservers are listed when
> > > > running ntpq> pe.
> > > >
> > > > So, and this is a problem with ntpd on FC2. On FC6 ncpd seems to
> > > > handle an ititial "no Internet connection available" ok, and when I
> > > > make the connection to the Internet all the timeservers are listed on
> > > > ntpq> pe. Back to the FC2 problem.
> > > >
> > > > Smoothwall is running, but dialup connection is down. Boot up the
> > > > machine on the LAN that has the Internet timeservers in
> > > > /etc/ntp.conf. Ntpd is started on bootup, but can't find the
> > > > timeservers, as there is no Internet connection, so ntpd decides to
> > > > go out to lunch.
> > > >
> > > > The sort of script that I'm looking for is one that will be either
> > > > run from /etc/rc.d/rc.local, but without delaying, hanging, stalling
> > > > the bootup sequence, or being run post bootup as root. A cron job
> > > > won't do this, as it runs at a specific time. This script needs to be
> > > > run either during, or post bootup.
> > > >
> > > > So this is the script I need. Either started with
> > > > /etc/init.d/rc.local. or post boot up
> > > >
> > > > Ping an Internet address every minute. When a response is received
> > > > showing an active Internet connection, then run
> > > > /usr/local/bin/ntp-restart.
> > > >
> > > > Perhaps I'm asking too much.
> > > >
> > > > Nigel.
> > >
> > > Why the obsession with ntp? The on board clock should be able maintain
> > > accurate time for at least a day or two.
> >
> > I'm trying to solve a problem here, not trying to start a rant on whether
> > to use ntp or not.
> >
> > This machine has problems with the time, so I'm trying to resolve it.
> > That's not much to ask, is it?
>
> Not trying to start a flame war. Just curious why you don't ping your
> ISP. Wouldn't that do serve the same purpose that you are trying to
> achieve?
I'm not bothered who I ping, as long as they dont't take offence at being
pinged. The whole objective is to get a response to a ping, that will verify
that the Internet connection is up.
A positive response to the ping should then trigger the running
of /usr/local/bin/ntp-restart, which should result in all 6 timeservers
listed when running ntpq> pe.
You may not aware of this incident which occurred over two years ago
concerning NTP servers,
http://lists.ntp.isc.org/pipermail/questions/2004-January/002141.html
. So please bother your ISP. They're getting paid to take your ping.
>
> > Nigel.
