I'm looking to add a crontab entry to execute a script every 30 minutes, on the hour and 30 minutes past the hour or something close. I have the following, but it doesn't seem to run on 0.
我希望添加一个crontab条目，以便每30分钟执行一次脚本，时间是小时30分，时间是小时30分。我有以下内容，但它似乎不在0上运行。
*/30 * * * *
What string do I need to use?
我需要使用什么字符串?
The cron is running on OSX.
cron在OSX上运行。
6 个解决方案
#1
434
Do:
做的事:
0,30 * * * * your_command
#2
70
Try this:
试试这个:
0,30 * * * * your command goes here
According to the official Mac OS X crontab(5) manpage, the / syntax is supported. Thus, to figure out why it wasn't working for you, you'll need to look at the logs for cron. In those logs, you should find a clear failure message.
根据官方的Mac OS X crontab(5)手册，支持/语法。因此，要找出它为什么不适合您，您需要查看cron的日志。在这些日志中，您应该找到一个明确的失败消息。
Note: Mac OS X appears to use Vixie Cron, the same as Linux and the BSDs.
注意:Mac OS X似乎使用了Vixie Cron，与Linux和BSDs相同。
#3
59
crontab does not understand "intervals", it only understands "schedule"
crontab不理解“间隔”，它只理解“schedule”
valid hours: 0-23 -- valid minutes: 0-59
有效时间:0-23——有效时间:0-59
example #1
示例# 1
30 * * * * your_command
你的命令
this means "run when the minute of each hour is 30" (would run at: 1:30, 2:30, 3:30, etc)
这句话的意思是“在每小时的一分钟是30的时候跑步”(在1点30分、2点30分、3点30分等等)
example #2
例# 2
*/30 * * * * your_command
* * * * *你的命令
this means "run when the minute of each hour is evenly divisible by 30" (would run at: 1:30, 2:00, 2:30, 3:00, etc)
这意味着“每小时的一分钟被30整除时跑步”(跑步时间为:1:30,2:00,2:30,3:00，等等)
example #3
示例# 3
0,30 * * * * your_command
0,30 * * * * your_command
this means "run when the minute of each hour is 0 or 30" (would run at: 1:30, 2:00, 2:30, 3:00, etc)
这意味着“在每小时的一分钟为0或30时跑步”(跑步时间为:1:30、2:00、2:30、3:00等)
it's another way to accomplish the same results as example #2
这是实现与示例#2相同结果的另一种方法
example #4
示例# 4
19 * * * * your_command
你的命令
this means "run when the minute of each hour is 19" (would run at: 1:19, 2:19, 3:19, etc)
这句话的意思是“当每小时的一分钟是19的时候跑步”(跑步时间是:1点19分，2点19分，3点19分，等等)
example #5
例# 5
*/19 * * * * your_command
你的命令
this means "run when the minute of each hour is evenly divisible by 19" (would run at: 1:19, 1:38, 1:57, 2:19, 2:38, 2:57 etc)
这意味着“当每小时的一分钟被19整除时，跑步”(跑步时间为:1:19,1:38,1:57,2:19,2:38,2:57等等)
note: several refinements have been made to this post by various users including the author
注意:包括作者在内的不同用户对这篇文章做了一些改进
#4
9
If your cron job is running on Mac OS X only, you may want to use launchd instead.
如果你的cron作业只在Mac OS X上运行，你可能需要使用launchd。
From Scheduling Timed Jobs (official Apple docs):
从日程安排到乔布斯(苹果官方文档):
Note: Although it is still supported, cron is not a recommended solution. It has been deprecated in favor of launchd.
注意:尽管仍然支持cron，但它不是推荐的解决方案。它已被弃用，以支持launchd。
You can find additional information (such as the launchd Wikipedia page) with a simple web search.
您可以通过简单的web搜索找到其他信息(例如启动Wikipedia页面)。
#5
5
You mention you are using OS X- I have used cronnix in the past. It's not as geeky as editing it yourself, but it helped me learn what the columns are in a jiffy. Just a thought.
你说你在用OS X-我以前用过cronnix。它并不像你自己编辑它那样令人讨厌，但它帮助我迅速了解了专栏是什么。只是一个想法。
#6
1
You can use both of ',' OR divide '/' symbols.
But, '/' is better.
Suppose the case of 'every 5 minutes'. If you use ',', you have to write the cron job as following:
可以同时使用' '或'/'符号。但是,“/”更好。假设是“每5分钟一次”。如果你使用'，'，你必须写cron job如下:
0,5,10,15,20,25,30,35,.... * * * * your_command
It means run your_command in every hour in all of defined minutes: 0,5,10,...
However, if you use '/', you can write the following simple and short job:
它意味着在所有定义的分钟内每小时运行your_command: 0,5,10，…但是，如果你使用'/'，你可以写出以下简单而简短的工作:
*/5 * * * * your_command
It means run your_command in the minutes that are dividable by 5 or in the simpler words, '0,5,10,...'
So, dividable symbol '/' is the best choice always;
它的意思是运行你的命令在可以被5或更简单的单词，'0,5,10，…所以，可除符号/'是最好的选择;
#1
434
Do:
做的事:
0,30 * * * * your_command
#2
70
Try this:
试试这个:
0,30 * * * * your command goes here
According to the official Mac OS X crontab(5) manpage, the / syntax is supported. Thus, to figure out why it wasn't working for you, you'll need to look at the logs for cron. In those logs, you should find a clear failure message.
根据官方的Mac OS X crontab(5)手册，支持/语法。因此，要找出它为什么不适合您，您需要查看cron的日志。在这些日志中，您应该找到一个明确的失败消息。
Note: Mac OS X appears to use Vixie Cron, the same as Linux and the BSDs.
注意:Mac OS X似乎使用了Vixie Cron，与Linux和BSDs相同。
#3
59
crontab does not understand "intervals", it only understands "schedule"
crontab不理解“间隔”，它只理解“schedule”
valid hours: 0-23 -- valid minutes: 0-59
有效时间:0-23——有效时间:0-59
example #1
示例# 1
30 * * * * your_command
你的命令
this means "run when the minute of each hour is 30" (would run at: 1:30, 2:30, 3:30, etc)
这句话的意思是“在每小时的一分钟是30的时候跑步”(在1点30分、2点30分、3点30分等等)
example #2
例# 2
*/30 * * * * your_command
* * * * *你的命令
this means "run when the minute of each hour is evenly divisible by 30" (would run at: 1:30, 2:00, 2:30, 3:00, etc)
这意味着“每小时的一分钟被30整除时跑步”(跑步时间为:1:30,2:00,2:30,3:00，等等)
example #3
示例# 3
0,30 * * * * your_command
0,30 * * * * your_command
this means "run when the minute of each hour is 0 or 30" (would run at: 1:30, 2:00, 2:30, 3:00, etc)
这意味着“在每小时的一分钟为0或30时跑步”(跑步时间为:1:30、2:00、2:30、3:00等)
it's another way to accomplish the same results as example #2
这是实现与示例#2相同结果的另一种方法
example #4
示例# 4
19 * * * * your_command
你的命令
this means "run when the minute of each hour is 19" (would run at: 1:19, 2:19, 3:19, etc)
这句话的意思是“当每小时的一分钟是19的时候跑步”(跑步时间是:1点19分，2点19分，3点19分，等等)
example #5
例# 5
*/19 * * * * your_command
你的命令
this means "run when the minute of each hour is evenly divisible by 19" (would run at: 1:19, 1:38, 1:57, 2:19, 2:38, 2:57 etc)
这意味着“当每小时的一分钟被19整除时，跑步”(跑步时间为:1:19,1:38,1:57,2:19,2:38,2:57等等)
note: several refinements have been made to this post by various users including the author
注意:包括作者在内的不同用户对这篇文章做了一些改进
#4
9
If your cron job is running on Mac OS X only, you may want to use launchd instead.
如果你的cron作业只在Mac OS X上运行，你可能需要使用launchd。
From Scheduling Timed Jobs (official Apple docs):
从日程安排到乔布斯(苹果官方文档):
Note: Although it is still supported, cron is not a recommended solution. It has been deprecated in favor of launchd.
注意:尽管仍然支持cron，但它不是推荐的解决方案。它已被弃用，以支持launchd。
You can find additional information (such as the launchd Wikipedia page) with a simple web search.
您可以通过简单的web搜索找到其他信息(例如启动Wikipedia页面)。
#5
5
You mention you are using OS X- I have used cronnix in the past. It's not as geeky as editing it yourself, but it helped me learn what the columns are in a jiffy. Just a thought.
你说你在用OS X-我以前用过cronnix。它并不像你自己编辑它那样令人讨厌，但它帮助我迅速了解了专栏是什么。只是一个想法。
#6
1
You can use both of ',' OR divide '/' symbols.
But, '/' is better.
Suppose the case of 'every 5 minutes'. If you use ',', you have to write the cron job as following:
可以同时使用' '或'/'符号。但是,“/”更好。假设是“每5分钟一次”。如果你使用'，'，你必须写cron job如下:
0,5,10,15,20,25,30,35,.... * * * * your_command
It means run your_command in every hour in all of defined minutes: 0,5,10,...
However, if you use '/', you can write the following simple and short job:
它意味着在所有定义的分钟内每小时运行your_command: 0,5,10，…但是，如果你使用'/'，你可以写出以下简单而简短的工作:
*/5 * * * * your_command
It means run your_command in the minutes that are dividable by 5 or in the simpler words, '0,5,10,...'
So, dividable symbol '/' is the best choice always;
它的意思是运行你的命令在可以被5或更简单的单词，'0,5,10，…所以，可除符号/'是最好的选择;