As the other commentators said, if uptime reports 7 days of uptime, the system hasn't rebooted in that while. If the reboot command is not on the executing shell's PATHcron might simply not find it. Some systems don't have the reboot command, in which case you'd need to use shutdown -r now.
I think the best answer I can give you is to get a sysadmin who can find out what's wrong with the box and why reboots take so long. Check the man page for the cron you have installed. It can do various things, depending on the implementation - like setting only specific variables i.
Apart from the incorrect first asterix in time definition, I believe the "root" string is incorrect, and the file should look like:.
If you want to set root's crontab, you have to run the crontab or whatever you use to set the jobs specification command as root.
Sign up to join this community. The best answers are voted up and rise to the top. Home Questions Tags Users Unanswered. Cronjob for rebooting everyday Ask Question. Asked 7 years, 4 months ago. Active 6 years, 4 months ago. Viewed 21k times. What is wrong? ChocoDeveloper ChocoDeveloper 1 1 gold badge 4 4 silver badges 9 9 bronze badges. Mat Because I don't want surprises. Sometimes it goes down, and then it takes hours to come back.
The delay in coming back only happens when it's been up for too long. So I prefer to reboot everyday at 5 am when there aren't many visits it's a web server. It comes back so fast that it manages to answer pending requests before they time out.
I'm not a sysadmin, so there might be a better way obviously. But right now I need this. Note that while this doesn't explain your issue, your crontab is wrong. It'll fire every minute between 5am and 6am.
DennisKaarsemaker Thanks, I will try that. ChocoDeveloper I'd guess that sometimes taking a while to come back is a fsck being forced after X days. Unfortunately, rebooting daily won't actually stop that. In fact, there is also a fsck after Y mounts, so it'll make it happen more.Crontab is very important and useful to schedule jobs and task in Linux.
As per our requirement we can schedule task to execute in background. We can also schedule command and scripts to execute on particular time interval.Scheduling Tasks in Linux - The CRONTAB Command
In this tutorial I am going to explain top 20 crontab examples. Above command will edit crontab of current logged in user.
You you set a cron to execute on specific days. In this example script will execute and run on each Monday and Saturday at 3PM. If you want to scheduled a task to execute on selected months. Below example will help to set cron to execute on each March,Jun and October.
It is not possible to execute a script only on first Sunday. To execute the a script on every 20 second is not possible but using below example to you can set it. By default cron result sends to current user where cron is scheduled.
But you redirect it to another account. You can set some useful scripts to execute on system reboot. Below example will help to set cron to execute on system reboot. Keep backup of all scheduled cron in a file. Follow the below to backup and restore all scheduled cron. I hope this article will be helpful to understand to scheduled task in Linux or Unix System. If you find this tutorial helpful please share with your friends to keep it alive. For more helpful topic browse my website www.
I placed a record reboot but it is too early for my script. How to execute it sometime after reboot? Is the script only ever intended to run one minute after boot up, or can it be used at other times, too? In the former case, you can add sleep 60 to the beginning of your script, or in the latter case, add it to the crontab file:.
If you need to execute something after reboot when network will become available, for example, you can write systemd unit that will be executed at required time of course this will work only on systems with systemd. Sign up to join this community. The best answers are voted up and rise to the top. Home Questions Tags Users Unanswered. Asked 7 years, 4 months ago. Active 4 months ago. Viewed k times. Yurij73 Yurij73 1, 5 5 gold badges 17 17 silver badges 29 29 bronze badges.
Why is it too early? Maybe an init script would be more suitable by regarding dependencies, e. So, test it and see if it works for you. Sounds like a case for Upstart? Active Oldest Votes. Or use a command line option to tweak the delay e. AndresAngel - I'm sorry, I don't know. Envek Envek 2 2 silver badges 4 4 bronze badges. I would use at. Sign up or log in Sign up using Google. Sign up using Facebook. Sign up using Email and Password.Cron is a tool for configuring scheduled tasks on Unix systems.
It is used to schedule commands or scripts to run periodically and at fixed intervals. Tasks range from backing up the user's home folders every day at midnight, to logging CPU information every hour.
The command crontab cron table is used to edit the list of scheduled tasks in operation, and is done on a per-user basis; each user including root has their own crontab. The first time you run crontab you'll be prompted to select an editor; if you are not sure which one to use, choose nano by pressing Enter.
The layout for a cron entry is made up of six components: minute, hour, day of month, month of year, day of week, and the command to be executed. To run a command every time the Raspberry Pi starts up, write reboot instead of the time and date. For example:. This will run your Python script every time the Raspberry Pi reboots. Editing crontab Run crontab with the -e flag to edit the cron table: crontab -e Select an editor The first time you run crontab you'll be prompted to select an editor; if you are not sure which one to use, choose nano by pressing Enter.
Add a scheduled task The layout for a cron entry is made up of six components: minute, hour, day of month, month of year, day of week, and the command to be executed. View scheduled tasks View your currently saved scheduled tasks with: crontab -l Run a task on reboot To run a command every time the Raspberry Pi starts up, write reboot instead of the time and date.It seems that all computers at some time or another need a reboot.
I tried several options, but the only full proof solution was to simply reboot. The script will reboot several times if no Wi-Fi is detected. If, after three tries, Wi-Fi is still not available, it will reboot after a longer interval.
The cron job is setup by simply editing the cron tab file. You need to replace the path above with the path to where the bash shell will be placed when you create it. You can adjust this to your system as required by simply replacing 5 in the command with any number you want i. You can adjust the path shown in line 2 one of the bash script to point to where you want to put your python script file. The permissions of the bash Script file need to be changed so that the cron job will be able to execute.
Change to the directory of the bash Script and perform the following command. Using the above code as a guide, you may need to correct the IP address and to set the delay the script will wait before testing the Wi-Fi after three failures.
You can adjust this to your access code IP address.
Top 20 Crontab Examples To Schedule Tasks
The best way to test if the IP address will work is to run the following command in a terminal window:. The maximum delay before retesting the Wi-Fi after a reboot is adjusted in line Right now it is set to 60 minutes.
The code is designed to test and if needed, reboot the Raspberry Pi three time as set by the cron interval i. If no Wi-Fi is detected, the retest time will increase to the interval shown in line So if you simply unplug your router and wait 20 minutes, you may notice that your Raspberry Pi is rebooting every 5 minutes as specified in the cron job. I actually adjusted this interval to just 1 minute for testing.
After turning on your access point, you can look at the log file and you should see a log that the Raspberry Pi rebooted three times before going to the longer interval. In this case, it does not reboot until after the longer interval, but records that Wi-Fi is still not working.
I wrote a similar autoreboot script that among other things will wait for a longer time after a certain number of reboots. Like Like. Thanks glowinthedark! Updating the code to allow the time to increase is a good improvement.
By automating when the time is increased, the reset period goes up after a few tries, but you still have a chance for the device to auto correct once the service is returned.
I actually ended up improving the code on my RPi machines to allow just this feature but had not been able to update the blog. Thank for the comment and contribution. You are commenting using your WordPress. You are commenting using your Google account.
You are commenting using your Twitter account. You are commenting using your Facebook account. Notify me of new comments via email. Notify me of new posts via email. This site uses Akismet to reduce spam. Learn how your comment data is processed. Search for: Search. Test the Script Cron Job setup: The cron job is setup by simply editing the cron tab file.
I want a reboot every 3rd Saturday of the month at I don't know what's wrong but I cannot find crontab. What I have is cron. If you want to reboot each night, add a cron entry using crontab -e as root to run shutdown -r each midnight. Another option is the at command, available on many Linux distributions. See the man page for more info, but the general syntax for your purpose would be:. As far as I know, you cannot use cron to schedule tasks for "last Friday of each month" or "third Thursday in each month".
What you can do, however ugly it seems, is to have a script run every Saturday at and then have this script determine if this particular Saturday is the third Saturday of the week can be done using date and maybe cal commands. I hope this helps. I have not found an elagant solution to this problem.
I found this thread, because I was searching for a solution for the same problem.
The reason you want to call the file zzwhatever is to make sure it's the last job called after all other jobs. To make sure just do an ls -l in the directory and verify it's the last file. Sign up to join this community. The best answers are voted up and rise to the top. Home Questions Tags Users Unanswered. Ask Question. Asked 9 years, 9 months ago. Active 3 years, 5 months ago. Viewed k times. I'm new in Linux and I want to schedule a reboot at midnight.
Automatic Raspberry Pi Reboot Script
Stack Overflow for Teams is a private, secure spot for you and your coworkers to find and share information. I'm using a Raspberry Pi for a status display, but for whatever reason it gets incredabbly sluggish after a day or so of running so I wanted to reboot it every day so I setup a cron job to do that every morning at But, it doesn't seem to be working.
Is there anything special about using cron to do a reboot? The second line works just fine, but I can't seem to get the restart command to work. It doesn't even output anything to the log. Try using the fully specified path to shutdown. Learn more. Using Cron to Reboot Ask Question. Asked 7 years ago. Active 5 years, 5 months ago. Viewed 8k times.
Azdle Azdle 1, 1 1 gold badge 13 13 silver badges 19 19 bronze badges. You need to execute shutdown and reboot as root. Try to find out why your status display application is becoming sluggish. Ken, that is the root's crontab. Basile, I know and I will figure it out eventually but we've got bigger fish to fry right now.
Active Oldest Votes. Yep, that was the problem. I'm kinda curious why it wouldn't have given me an error message. It probably did You need to edit the root user crontab sudo crontab -e then. Scott Goodgame Scott Goodgame 3 3 bronze badges. Sign up or log in Sign up using Google. Sign up using Facebook. Sign up using Email and Password.
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