Igor,
I believe that the NTP protocol recommends 3 time servers as part of the
algorithm calls for checking for network latency, and keeping in mind that
the "authority" time server may drift as well.
If you think that your 740 is "more stable", add that to the list of time
servers (I think that the filer will allow a query), then it will get even
more interesting. I know that on unix servers, it is suggested that
localhost be added as a low priority host - that way, just in case the
network bogs down, it can rely on the local clock without having to reset it
all the time.
Hope this helps,
Jim
-----Original Message-----
From: Igor Schein [mailto:igor@txc.com]
Sent: Friday, April 12, 2002 4:00 PM
To: toasters(a)mathworks.com
Subject: time sync issue
Hi,
I have 2 filers, 740 running 6.1.1R2 and 840 running 6.2R1.
I have the same timed setup on both machines:
timed.enable on
timed.log on
timed.max_skew 30m
timed.min_skew 50
timed.proto ntp
timed.sched hourly
timed.servers ntphost1
Here's how the messages look for 740 filer:
Time reported by time server ntphost1 is Fri Apr 12 13:10:54 GMT 2002 (skew
+0.088 secs).
Time reported by time server ntphost1 is Fri Apr 12 14:08:34 GMT 2002 (skew
+0.055 secs).
Time reported by time server ntphost1 is Fri Apr 12 14:57:16 GMT 2002 (skew
+0.129 secs).
Time reported by time server ntphost1 is Fri Apr 12 17:11:09 GMT 2002 (skew
+0.051 secs).
Time reported by time server ntphost1 is Fri Apr 12 18:01:03 GMT 2002 (skew
+0.058 secs).
Time reported by time server ntphost1 is Fri Apr 12 19:01:11 GMT 2002 (skew
+0.116 secs).
Time reported by time server ntphost1 is Fri Apr 12 19:55:54 GMT 2002 (skew
+0.080 secs).
Time reported by time server ntphost1 is Fri Apr 12 20:06:43 GMT 2002 (skew
+0.054 secs).
Time reported by time server ntphost1 is Fri Apr 12 20:37:57 GMT 2002 (skew
+0.098 secs).
Time reported by time server ntphost1 is Fri Apr 12 21:05:39 GMT 2002 (skew
+0.102 secs).
The skew is always positive and always small ( 0.1 secs or less ).
Now here're the messages for 840 filer:
Time reported by time server ntphost1 is Fri Apr 12 12:05:10 GMT 2002 (skew
-0.177 secs).
Time reported by time server ntphost1 is Fri Apr 12 13:05:32 GMT 2002 (skew
-0.221 secs).
Time reported by time server ntphost1 is Fri Apr 12 13:52:17 GMT 2002 (skew
+0.238 secs).
Time reported by time server ntphost1 is Fri Apr 12 14:03:44 GMT 2002 (skew
-0.065 secs).
Time reported by time server ntphost1 is Fri Apr 12 16:08:06 GMT 2002 (skew
-0.101 secs).
Time reported by time server ntphost1 is Fri Apr 12 17:00:57 GMT 2002 (skew
-0.102 secs).
Time reported by time server ntphost1 is Fri Apr 12 18:06:15 GMT 2002 (skew
-0.199 secs).
Time reported by time server ntphost1 is Fri Apr 12 18:53:44 GMT 2002 (skew
+0.185 secs).
Time reported by time server ntphost1 is Fri Apr 12 19:08:31 GMT 2002 (skew
-0.243 secs).
Time reported by time server ntphost1 is Fri Apr 12 20:01:58 GMT 2002 (skew
-0.140 secs).
The skew's sign jumps back and forth, and the absolute value is over 0.2
secs ( becomes
as high as 0.3 secs, which prompts make utility on clients to complain ).
What can be wrong with the clock on 840 filer? I suppose I can change
timed.sched to
sync more frequently, but I am just curious about the nature of the issue.
Thanks
Igor