脚本的部分最初看起来像这样：

FILES=$($SSH_BINARY -i $SSH_KEY $SSH_USER@$REMOTE_HOST "ls $REMOTE_DIRECTORY")
echo "Got files = $FILES"

我在该行上方添加了一个echo语句(如下所示),以证明它不是路径或变量问题：

echo "$SSH_BINARY -i $SSH_KEY $SSH_USER@$REMOTE_HOST \"ls $REMOTE_DIRECTORY\""

如果我获取结果输出行并以相同的用户cron(root)运行它,它可以正常工作.

认为它可能与赋值给变量有关,我修改了FILES =行来读取(因此,将输出直接放入我的last_run_output文件中)：

$SSH_BINARY -vv -i $SSH_KEY $SSH_USER@$REMOTE_HOST "ls $REMOTE_DIRECTORY"

cron条目如下所示：

34 * * * * /root/path/to/my/script/get_logs.sh > /root/path/to/last_run_output 2>&1

所以,除了PATH,变量赋值和权限问题之外,我开始在ssh中使用调试标志.我从命令行运行一次,然后从cron运行,并比较输出.以下是差异的一些亮点：

– 方是不成功的尝试,方是成功的尝试,在cron之外运行.

@@ -87,9 +77,7 @@
 debug1: Remote: X11 forwarding disabled.
 debug1: Remote: Forced command: /home/sshacs/acssshsink netstorageuser
 debug1: Authentication succeeded (publickey).
-debug2: fd 4 setting O_NONBLOCK
 debug2: fd 5 setting O_NONBLOCK
-debug2: fd 6 setting O_NONBLOCK
 debug1: channel 0: new [client-session]
 debug2: channel 0: send open
 debug1: Entering interactive session.

我无法解释为什么在从cron运行时在debug2中提到这些额外的文件描述符,但它似乎是相关的(通知读取< = 0 rfd 4 len 0 line below)：

@@ -100,20 +88,672 @@
 debug2: callback done
 debug2: channel 0: open confirm rwindow 0 rmax 32768
 debug2: channel 0: rcvd adjust 131072
-debug2: channel 0: read<=0 rfd 4 len 0
-debug2: channel 0: read Failed
-debug2: channel 0: close_read
-debug2: channel 0: input open -> drain
-debug2: channel 0: ibuf empty
-debug2: channel 0: send eof
-debug2: channel 0: input drain -> closed
+  [[ Very large output of the ls command ]]
+debug1: client_input_channel_req: channel 0 rtype exit-status reply 0
 debug2: channel 0: rcvd eof
 debug2: channel 0: output open -> drain
 debug2: channel 0: obuf empty
 debug2: channel 0: close_write
 debug2: channel 0: output drain -> closed
-debug1: client_input_channel_req: channel 0 rtype exit-status reply 0
 debug2: channel 0: rcvd close
+debug2: channel 0: close_read
+debug2: channel 0: input open -> closed
 debug2: channel 0: almost dead
 debug2: channel 0: gc: notify user
 debug2: channel 0: gc: user detached

任何想法都非常感谢.