k***r
发帖数: 4260 | 1 有几台机器在不同的data center，需要比较准时地在整点向服务器
报告，前后差一两分钟问题不大。但是本机的时间不能保证，而且
不能调整，只能在Application起来的时候从网上拿一个比较准的时
间而不依赖系统时间。有什么NTP component推荐吗？或者有什么
free的报告时间的web service？ |
k***r
发帖数: 4260 | |
g*****g
发帖数: 34805 | 3 Counting on external web service for a task like this is a
bad idea. You may get system time from the same DB server and
most DB servers support that.
【在 k***r 的大作中提到】
: 有几台机器在不同的data center，需要比较准时地在整点向服务器
: 报告，前后差一两分钟问题不大。但是本机的时间不能保证，而且
: 不能调整，只能在Application起来的时候从网上拿一个比较准的时
: 间而不依赖系统时间。有什么NTP component推荐吗？或者有什么
: free的报告时间的web service？
|
m******t
发帖数: 2416 | 4 Why not just put ntpdate in a cronjob?
【在 k***r 的大作中提到】
: 有几台机器在不同的data center，需要比较准时地在整点向服务器
: 报告，前后差一两分钟问题不大。但是本机的时间不能保证，而且
: 不能调整，只能在Application起来的时候从网上拿一个比较准的时
: 间而不依赖系统时间。有什么NTP component推荐吗？或者有什么
: free的报告时间的web service？
|
F****n
发帖数: 3271 | 5 Try to separate clock synchronization and program synchronization. On each
workstation install a timer synchronized to a timer service. Use the local
timer to synchronize local program.
【在 k***r 的大作中提到】
: 找到一个webservice，奇怪的是getUTCTime只返回时间没有日期
: http://www.nanonull.com/TimeService/TimeService.asmx
|
k***r
发帖数: 4260 | 6 A mix of unix and Windows machines makes it a little messy.
Plus, I'm not supposed to touch the local clock.
【在 m******t 的大作中提到】
: Why not just put ntpdate in a cronjob?
|
k***r
发帖数: 4260 | 7 In my case, the DB server isn't exposed. Although I can
provide a web service to wrap the DB time but I'm assuming
using an external web service is even easier, unless it's
not reliable...
【在 g*****g 的大作中提到】
: Counting on external web service for a task like this is a
: bad idea. You may get system time from the same DB server and
: most DB servers support that.
|
g*****g
发帖数: 34805 | 8 If it's not a paid service with 99.9% guarranteed up time,
it's not reliable. Anything can break will break.
If it's a critical service for the product and you can't
deliver because a free service you happen to find on Internet
is broken. You'll look very bad.
And I don't get that the DB Server isn't exposed. Can't you
get it through SQL query although it may vary from vendor to
vendor.
【在 k***r 的大作中提到】
: In my case, the DB server isn't exposed. Although I can
: provide a web service to wrap the DB time but I'm assuming
: using an external web service is even easier, unless it's
: not reliable...
|
k***r
发帖数: 4260 | 9 The reliability of a free service is a concern.
Using a time web service provided by my server is probably
a good idea - it needs to report to my server anyway. Just
a little bit more work to do.
Thanks for the suggestions!
【在 g*****g 的大作中提到】
: If it's not a paid service with 99.9% guarranteed up time,
: it's not reliable. Anything can break will break.
: If it's a critical service for the product and you can't
: deliver because a free service you happen to find on Internet
: is broken. You'll look very bad.
: And I don't get that the DB Server isn't exposed. Can't you
: get it through SQL query although it may vary from vendor to
: vendor.
|
g*****g
发帖数: 34805 | 10 It's a DB server, why can't you use oldschool SQL query to get it,
web service sounds overkill for me.
【在 k***r 的大作中提到】
: The reliability of a free service is a concern.
: Using a time web service provided by my server is probably
: a good idea - it needs to report to my server anyway. Just
: a little bit more work to do.
: Thanks for the suggestions!
|
k***r
发帖数: 4260 | 11 Let's say, the servers that need to report back are on customers'
sites and the only interface for it to ping home is HTTP.
By web service I meant it in a generic way. It could be a web
page that simply prints out "11/19/2008 18:24:30".
【在 g*****g 的大作中提到】
: It's a DB server, why can't you use oldschool SQL query to get it,
: web service sounds overkill for me.
|
r*****l
发帖数: 2859 | 12 Is there an operation team in your company that
maintenance the machine and the OS?
It's ops responsibility to make the server time
accurate.
【在 k***r 的大作中提到】
: A mix of unix and Windows machines makes it a little messy.
: Plus, I'm not supposed to touch the local clock.
|
r*****l
发帖数: 2859 | 13 And have Java read the local time.
【在 r*****l 的大作中提到】
: Is there an operation team in your company that
: maintenance the machine and the OS?
: It's ops responsibility to make the server time
: accurate.
|
k***r
发帖数: 4260 | 14 Some of the machines belong to, let's say, some
customers, that don't guarantee to keep up the time
on the servers. So I can't rely on local time...
【在 r*****l 的大作中提到】
: Is there an operation team in your company that
: maintenance the machine and the OS?
: It's ops responsibility to make the server time
: accurate.
|
