blocks|key|1023938|text|*+*+*+*+*+myjob.sh+>>+/var/log/myjob.log+2>&1|type|code-block|depth|inlineStyleRanges|entityRanges|data|syntax|javascript|1023939|将cron作业的所有输出记录到/var/+log+/myjob.log中|unstyled|1023940|您可以使用mail发送电子邮件。大多数系统都会通过电子邮件将未经处理的cron作业输出发送给超级用户或相应的用户。|offset|length|style|CODE|1023941|entityMap^0|0|0|5|4|Z|4|0^^$0|@$1|2|3|4|5|6|7|O|8|@]|9|@]|A|$B|C]]|$1|D|3|E|5|F|7|P|8|@]|9|@]|A|$]]|$1|G|3|H|5|F|7|Q|8|@$I|R|J|S|K|L]|$I|T|J|U|K|L]]|9|@]|A|$]]|$1|M|3|-4|5|F|7|V|8|@]|9|@]|A|$]]]|N|$]]

<pre><code>* * * * * myjob.sh &gt;&gt; /var/log/myjob.log 2&gt;&amp;1
</code></pre>

will log all output from the cron job to /var/log/myjob.log

You might use <code>mail</code> to send emails. Most systems will send unhandled <code>cron</code> job output by email to root or the corresponding user.

blocks|key|1023997|text|默认情况下，cron日志记录到/var/log/syslog，因此您可以使用以下命令查看与cron相关的条目：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1023998|grep+CRON+/var/log/syslog|code-block|syntax|javascript|1023999|https://askubuntu.com/questions/56683/where-is-the-cron-crontab-log|offset|length|1024000|entityMap|0|LINK|mutability|MUTABLE|url^0|0|0|0|1V|0|0^^$0|@$1|2|3|4|5|6|7|R|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|S|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|T|8|@]|9|@$I|U|J|V|1|W]]|A|$]]|$1|K|3|-4|5|6|7|X|8|@]|9|@]|A|$]]]|L|$M|$5|N|O|P|A|$Q|H]]]]

By default cron logs to /var/log/syslog so you can see cron related entries by using:

<pre><code>grep CRON /var/log/syslog
</code></pre>

<a href="https://askubuntu.com/questions/56683/where-is-the-cron-crontab-log">https://askubuntu.com/questions/56683/where-is-the-cron-crontab-log</a>

blocks|key|1024010|text|下面是我的代码：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1024011|*+*+*+*+*+your_script_fullpath+>>+your_log_path+2>&1|code-block|syntax|javascript|1024012|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

Here is my code:

<pre><code>* * * * * your_script_fullpath &gt;&gt; your_log_path 2&gt;&amp;1
</code></pre>

blocks|key|1024212|text|cron已经将它运行的每个作业的标准输出和标准错误通过邮件发送给cron作业的所有者。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|1024213|您可以在crontab文件中使用MAILTO=recipient将电子邮件发送到其他帐户。|1024214|要使其正常工作，您需要让邮件正常工作。递送到本地邮箱通常不是问题(事实上，ls+-l+"$MAIL"很可能会显示你已经收到了一些)，但要想将其从邮箱中发送到互联网上，需要正确配置MTA+(后缀、Sendmail等)以连接到世界。|1024215|如果没有输出，则不会生成电子邮件。|1024216|一种常见的安排是将输出重定向到一个文件，在这种情况下，cron守护进程当然不会看到作业返回任何输出。一种变体是将标准输出重定向到一个文件(或者编写脚本，使其永远不会打印任何内容--也许它将结果存储在数据库中，或者执行根本不输出任何内容的维护任务？)并且只有在出现错误消息时才会收到电子邮件。|1024217|要重定向这两个输出流，语法为|1024218|42+17+*+*+*+script+>>stdout.log+2>>stderr.log|code-block|syntax|javascript|1024219|注意我们是如何追加(double+>>)而不是覆盖，这样前一个作业的输出就不会被下一个作业的输出所取代。|1024220|正如这里的许多答案所建议的，您可以将两个输出流发送到单个文件；将第二个重定向替换为2>&1，以表明“标准错误应该去任何标准输出的地方”。(但我并不特别赞同这种做法。如果您并不真正期望标准输出上的任何东西，但可能忽略了一些东西，可能来自于从您的脚本调用的外部工具，那么它主要是有意义的。)|1024221|cron作业在您的主目录中运行，因此任何相对文件名都应该是相对于主目录的。如果要在主目录之外写入，显然需要单独确保您对目标文件具有写入访问权限。|1024222|一种常见的反模式是将所有内容重定向到/dev/null+(然后让Stack+Overflow帮助您找出当某些东西不工作时出了什么问题；但我们也看不到丢失的输出！)|1024223|在您的脚本中，确保将常规输出(实际结果，最好是机器可读的形式)和诊断(通常是为人类读者设置的格式)分开。在shell脚本中，|1024224|echo+"$results"++#+regular+results+go+to+stdout
echo+"$0:+something+went+wrong"+>&2|1024225|一些平台(例如GNU+Awk)允许您使用文件名/dev/stderr来表示错误消息，但这不能很好地移植；在Perl语言中，warn和die打印到标准错误；在Python语言中，写入sys.stderr或使用logging；在Ruby语言中，尝试使用$stderr.puts。还要注意错误消息应该如何包含生成诊断消息的脚本的名称。|1024226|entityMap^0|0|4|0|4|7|G|G|0|11|D|0|0|0|0|0|H|2|0|15|4|0|0|4|0|I|9|0|0|0|N|B|1P|4|1U|3|2I|A|2V|7|3G|C|0^^$0|@$1|2|3|4|5|6|7|1A|8|@$9|1B|A|1C|B|C]]|D|@]|E|$]]|$1|F|3|G|5|6|7|1D|8|@$9|1E|A|1F|B|C]|$9|1G|A|1H|B|C]]|D|@]|E|$]]|$1|H|3|I|5|6|7|1I|8|@$9|1J|A|1K|B|C]]|D|@]|E|$]]|$1|J|3|K|5|6|7|1L|8|@]|D|@]|E|$]]|$1|L|3|M|5|6|7|1M|8|@]|D|@]|E|$]]|$1|N|3|O|5|6|7|1N|8|@]|D|@]|E|$]]|$1|P|3|Q|5|R|7|1O|8|@]|D|@]|E|$S|T]]|$1|U|3|V|5|6|7|1P|8|@$9|1Q|A|1R|B|C]]|D|@]|E|$]]|$1|W|3|X|5|6|7|1S|8|@$9|1T|A|1U|B|C]]|D|@]|E|$]]|$1|Y|3|Z|5|6|7|1V|8|@$9|1W|A|1X|B|C]]|D|@]|E|$]]|$1|10|3|11|5|6|7|1Y|8|@$9|1Z|A|20|B|C]]|D|@]|E|$]]|$1|12|3|13|5|6|7|21|8|@]|D|@]|E|$]]|$1|14|3|15|5|R|7|22|8|@]|D|@]|E|$S|T]]|$1|16|3|17|5|6|7|23|8|@$9|24|A|25|B|C]|$9|26|A|27|B|C]|$9|28|A|29|B|C]|$9|2A|A|2B|B|C]|$9|2C|A|2D|B|C]|$9|2E|A|2F|B|C]]|D|@]|E|$]]|$1|18|3|-4|5|6|7|2G|8|@]|D|@]|E|$]]]|19|$]]

<code>cron</code> already sends the standard output and standard error of every job it runs by mail to the owner of the cron job.

You can use <code>MAILTO=recipient</code> in the <code>crontab</code> file to have the emails sent to a different account.

For this to work, you need to have mail working properly. Delivering to a local mailbox is usually not a problem (in fact, chances are <code>ls -l "$MAIL"</code> will reveal that you have already been receiving some) but getting it off the box and out onto the internet requires the MTA (Postfix, Sendmail, what have you) to be properly configured to connect to the world.

If there is no output, no email will be generated.

A common arrangement is to redirect output to a file, in which case of course the cron daemon won't see the job return any output. A variant is to redirect standard output to a file (or write the script so it never prints anything - perhaps it stores results in a database instead, or performs maintenance tasks which simply don't output anything?) and only receive an email if there is an error message.

To redirect both output streams, the syntax is

<pre><code>42 17 * * * script &gt;&gt;stdout.log 2&gt;&gt;stderr.log
</code></pre>

Notice how we append (double <code>&gt;&gt;</code>) instead of overwrite, so that any previous job's output is not replaced by the next one's.

As suggested in many answers here, you can have both output streams be sent to a single file; replace the second redirection with <code>2&gt;&amp;1</code> to say "standard error should go wherever standard output is going". (But I don't particularly endorse this practice. It mainly makes sense if you don't really expect anything on standard output, but may have overlooked something, perhaps coming from an external tool which is called from your script.)

<code>cron</code> jobs run in your home directory, so any relative file names should be relative to that. If you want to write outside of your home directory, you obviously need to separately make sure you have write access to that destination file.

A common antipattern is to redirect everything to <code>/dev/null</code> (and then ask Stack Overflow to help you figure out what went wrong when something is not working; but we can't see the lost output, either!)

From within your script, make sure to keep regular output (actual results, ideally in machine-readable form) and diagnostics (usually formatted for a human reader) separate. In a shell script,

<pre><code>echo "$results" # regular results go to stdout
echo "$0: something went wrong" &gt;&amp;2
</code></pre>

Some platforms (and e.g. GNU Awk) allow you to use the file name <code>/dev/stderr</code> for error messages, but this is not properly portable; in Perl, <code>warn</code> and <code>die</code> print to standard error; in Python, write to <code>sys.stderr</code>, or use <code>logging</code>; in Ruby, try <code>$stderr.puts</code>. Notice also how error messages should include the name of the script which produced the diagnostic message.

blocks|key|1024322|text|使用命令crontab+-e，然后将cron作业编辑为|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|1024323|*+*+*+*+*+/path/file.sh+>+/pathToKeepLogs/logFileName.log+2>&1|code-block|syntax|javascript|1024324|这里，2>&1表示标准错误(2>)被重定向到标准输出(&1)所指向的同一文件描述符。|1024325|entityMap^0|4|A|0|0|3|4|E|2|R|2|0^^$0|@$1|2|3|4|5|6|7|O|8|@$9|P|A|Q|B|C]]|D|@]|E|$]]|$1|F|3|G|5|H|7|R|8|@]|D|@]|E|$I|J]]|$1|K|3|L|5|6|7|S|8|@$9|T|A|U|B|C]|$9|V|A|W|B|C]|$9|X|A|Y|B|C]]|D|@]|E|$]]|$1|M|3|-4|5|6|7|Z|8|@]|D|@]|E|$]]]|N|$]]

Use the command <code>crontab -e</code>, and then edit the cron jobs as
<pre><code>* * * * * /path/file.sh &gt; /pathToKeepLogs/logFileName.log 2&gt;&amp;1
</code></pre>
Here, <code>2&gt;&amp;1</code> indicates that the standard error (<code>2&gt;</code>) is redirected to the same file descriptor that is pointed by standard output (<code>&amp;1</code>).

blocks|key|1024122|text|如果您正在使用sudo运行某些命令，它将不允许这样做。Sudo需要一个tty。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1024123|entityMap^0|0^^$0|@$1|2|3|4|5|6|7|D|8|@]|9|@]|A|$]]|$1|B|3|-4|5|6|7|E|8|@]|9|@]|A|$]]]|C|$]]

Incase you're running some command with sudo, it won't allow it. Sudo needs a tty.

I want to know how I can see exactly what the cron jobs are doing on each execution. Where are the log files located? Or can I send the output to my email? I have set the email address to send the log when the cron job runs but I haven't received anything yet.

How to log cron jobs?

日志文件

Ruby语言

数据库

Python

Perl

我想知道如何才能确切地看到cron作业在每次执行中都在做什么。日志文件位于何处？或者我可以将输出发送到我的电子邮件中？我已经设置了当cron作业运行时发送日志的电子邮件地址，但是我还没有收到任何东西。

问如何记录cron作业？
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问如何记录cron作业？EN

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