Re: rdate issue
On 2007/05/13 23:06, John Nietzsche wrote: */5 * * * * /usr/sbin/rdate -4ncva -c corrects for leap seconds */5 * * * * /usr/sbin/rdate -4cva gw | and here you do it again i.e. you are correcting time coming from a source which is already corrected. I would really recommend against using rdate like this, it jumps the clock. ntpd skews the clock (makes it run slightly fast or slow until the time is correct), so you don't miss out on any seconds (which sometimes skips cron jobs, makes logging more confusing, and can cause a lot of trouble with some other applications).
Re: rdate issue
On Mon, 14 May 2007, Stuart Henderson wrote: On 2007/05/13 23:06, John Nietzsche wrote: */5 * * * * /usr/sbin/rdate -4ncva -c corrects for leap seconds */5 * * * * /usr/sbin/rdate -4cva gw | and here you do it again i.e. you are correcting time coming from a source which is already corrected. I would really recommend against using rdate like this, it jumps the clock. ntpd skews the clock (makes it run slightly fast or slow until the time is correct), so you don't miss out on any seconds (which sometimes skips cron jobs, makes logging more confusing, and can cause a lot of trouble with some other applications). While I agree with the advise, this is not true when the -a flag is given to rdate, in that case rdate uses adjtime(2). ntpd is of course much nicer, since its adjust the clock frequency as well, and poses a very light stress on the server: once time is synced, queries do not happen a lot. Not to speak of the ability to use time sensors and multiple time sources to provide redundancy. -Otto
Re: rdate issue
I would really recommend against using rdate like this, it jumps the clock. ntpd skews the clock (makes it run slightly fast or slow until the time is correct), so you don't miss out on any seconds (which sometimes skips cron jobs, makes logging more confusing, and can cause a lot of trouble with some other applications). the -a option fixes the skew problem. -a Use the adjtime(2) call to gradually skew the local time to the remote time rather than just hopping. I still recommend ntp if you need to continually update the clock. It's always worked for me in the past. Ntpd (AFIK) continually monitors the difference between your clock and the remote server to try and adjust the skew for a more accurate local clock. Rdate doesn't. Cheers, A
rdate issue
Dear gentleman/madam, i have a home network composed of 1 gateway and two boxes. All of them running openbsd 4.1 of course. I decided to get the time syncronization for all those boxes. In the gateway machine, i managed to get the following in crontab: */5 * * * * /usr/sbin/rdate -4ncva ptbtime1.ptb.de | /usr/bin/logger -t NTP In the other two boxes (lion and etosha) i have: */5 * * * * /usr/sbin/rdate -4cva gw | /usr/bin/logger -t NTP Everything is working ok except because of those two boxes always have a time about 20/22 seconds after my gateway time, like in the output for date command: [EMAIL PROTECTED] date Sun May 13 23:04:35 BRT 2007 [EMAIL PROTECTED] date Sun May 13 23:04:59 BRT 2007 [EMAIL PROTECTED] date Sun May 13 23:04:59 BRT 2007 Does anybody have any ideia about why it is happening ? Thanks in advance. best regards.
Re: rdate issue
John Nietzsche wrote: ... Everything is working ok except because of those two boxes always have a time about 20/22 seconds after my gateway time, like in the output for date command: [EMAIL PROTECTED] date Sun May 13 23:04:35 BRT 2007 [EMAIL PROTECTED] date Sun May 13 23:04:59 BRT 2007 [EMAIL PROTECTED] date Sun May 13 23:04:59 BRT 2007 Does anybody have any ideia about why it is happening ? yep. http://www.openbsd.org/faq/faq8.html#NTPerror ls -l /etc/localtime on all three boxes will probably make it clear what is going on. (look for the presence or absence of the word right in each...) Nick.
Re: rdate issue
I decided to get the time syncronization for all those boxes. In the gateway machine, i managed to get the following in crontab: */5 * * * * /usr/sbin/rdate -4ncva ptbtime1.ptb.de | /usr/bin/logger -t NTP snip Everything is working ok except because of those two boxes always have a time about 20/22 seconds after my gateway time, like in the output for date command: Have you considered running ntpd instead of rdate? If nothing more, the daemon removes the need to have crontabs updating the clock. I have no explanation for why the times are about 20 seconds out other than the gateway might be taking its time to wake up the rdate daemon. Cheers, A
Re: rdate issue
On 5/13/07, John Nietzsche [EMAIL PROTECTED] wrote: In the other two boxes (lion and etosha) i have: */5 * * * * /usr/sbin/rdate -4cva gw | Everything is working ok except because of those two boxes always have a time about 20/22 seconds after my gateway time, like in the output for date command: don't use -c.
