Commands tagged cronjob

pauses exactly long enough to wake at the top of the hour

This one-liner is for cron jobs that need to provide some basic information about a filesystem and the time it takes to complete the operation. You can swap out the di command for df or du if that's your thing. The |& redirections the stderr and stdout to the mail command.

How to configure the variables.

TOFSCK=/path/to/mount

FSCKDEV=/dev/path/device

or

FSCKDEV=`grep $TOFSCK /proc/mounts | cut -f1 -d" "`

MAILSUB="weekly file system check $TOFSCK "

This command will log the output of your simple cronjobs to syslog, and syslog will take it from there. Works great for monitoring scripts which only produce simple output.

Advantages:

* This can be used by regular users, without modifying system files like /etc/syslog.conf

* Reduce cron spam to root@localhost (Please stop spaming the sysadmins)

* Uses common tools like syslog (and logrotate) so that you don't need to maintain yet another krufty logfile.

* Still ensures that the output is logged somewhere, for posterity. Perhaps it's stored the secure, central syslog server, for example.

* Seems to work fine on Ubuntu, CentOS, FreeBSD & MacOSX

if you need to install cron jobs in a given time range.

With this cron, rsync begins to sinchronize the contents of the local directory on /[VIPdirectory] with the directory /backup/[VIPdirectory] on the remote server X.X.X.X. Previously we need working on public/private-keys ssh to guarantee the acces to the remote server on X.X.X.X

It's very common to have cron jobs that send emails as their output, but the From: address is whatever account the cron job is running under, which is often not the address you want replies to go to. Here's a way to change the From: address right on the command line.

What's happening here is that the "--" separates the options to the mail client from options for the sendmail backend. So the -f and -F get passed through to sendmail and interpreted there. This works on even on a system where postfix is the active mailer - looks like postfix supports the same options.

I think it's possible to customize the From: address using mutt as a command line mailer also, but most servers don't have mutt preinstalled.

This is helpful for shell scripts, I use it in my custom php install script to schedule to delete the build files in 3 hours, as the php install script is completely automated and is made to run slow.

Does require at, which some environments without crontab still do have.

You can add as many commands to the at you want. Here's how I delete them in case the script gets killed. (trapped)

atq |awk '{print $1}'|xargs -iJ atrm J &>/dev/null

Chronic Bash function:

Note: use 'jobs' to list background tasks and fg/bg to take control of them.

I find it ugly & sexy at the same time isn't it ?

This command will tell lynx to read keystrokes from the specified file - which can be used in a cronjob to auto-login on websites that give you points for logging in once a day *cough cough* (which is why I used -accept_all_cookies).

For creating your keystroke file, use: