On Mon, Apr 12, 2004 at 10:39:16PM -0600, Rodolfo J. Paiz wrote: > > At 22:32 4/12/2004, you wrote: > >The new ntpdate will no longer make the brutal abrupt time adjustment > >that some of us got to know and 'love'. I am not sure which behavior > >is in the FC1/2 ntp package at this time but the "time"s they be a changing > >on this point. > > > >Read all about it on the ntp home pages and in the Fedora archives. > > Most interesting. The last thing I read on the subject was a huge diatribe > on the evils of ntpdate. ...... > Haven't had much time to STFW here, but can you point me to a URL or two? http://www.eecis.udel.edu/~mills/ntp/html/ntpdate.html ...."The functionality of this program is now available in the ntpd program. See the -q command line option in the ntpd - Network Time Protocol (NTP) daemon page. After a suitable period of mourning, the ntpdate program is to be retired from this distribution".... -q Exit the ntpd just after the first time the clock is set. This behavior mimics that of the ntpdate program, which is to be retired. The -g and -x options can be used with this option. -g Normally, ntpd exits if the offset exceeds the sanity limit, which is 1000 s by default. If the sanity limit is set to zero, no sanity checking is performed and any offset is acceptable. This option overrides the limit and allows the time to be set to any value without restriction; however, this can happen only once. After that, ntpd will exit if the limit is exceeded. This option can be used with the -q option. -x Normally, the time is slewed if the offset is less than the step threshold, which is 128 ms by default, and stepped if above the threshold. This option forces the time to be slewed in all cases. If the step threshold is set to zero, all offsets are stepped, regardless of value and regardless of the -x option. In general, this is not a good idea, as it bypasses the clock state machine which is designed to cope with large time and frequency errors Note: Since the slew rate is limited to 0.5 ms/s, each second of adjustment requires an amortization interval of 2000 s. Thus, an adjustment of many seconds can take hours or days to amortize. This option can be used with the -q option. But not all sources of time are ntp... So here is one idea to get folks jumping up and down..... In a pinch one can force the time in a brutal way. Find a host that returns the correct time of day. $ telnet 192.168.0.51 13 Trying 192.168.0.51... Connected to (192.168.0.51). Escape character is '^]'. 12 APR 2004 22:03:13 PDT Connection closed by foreign host. this can be cleaned up a bit frog=`telnet 192.168.0.51 13| grep ^[0-9]` echo $frog The system date date can be set with 'date'. A little script magic to do some sanity checking, translate month to a number etc. and get the instant 'good time' that some people like. # date [-u|--utc|--universal] [MMDDhhmm[[CC]YY][.ss]] It might better to do something like this first and find out if there is value in all this. frog=`telnet 192.168.0.51 13| grep ^[0-9]` logger "Time at 192.168.0.51 is $frog" Now an inspection of var/log/messages will tell you if you really want to play with this stuff. Apr 12 22:18:29 box1 bob: Time at 192.168.0.51 is 12 APR 2004 22:18:29 PDT Apr 12 22:18:31 box1 bob: Time at 192.168.0.51 is 12 APR 2004 22:18:31 PDT Apr 12 22:18:32 box1 bob: Time at 192.168.0.51 is 12 APR 2004 22:18:32 PDT Other 'services' can be abused... which is why most are turned off. $ grep time /etc/services daytime 13/tcp ;-) -- T o m M i t c h e l l /dev/null the ultimate in secure storage.
