Tag: cronjob

Cron Job fails with Error Message “(getpwnam() failed): No such file or directory”
On a CentOS server, cronjob did not work. Checking the log file found the following error message in /var/log/cron
```
Oct 24 18:35:01 CentOS-75-64-minimal crond[1546]: (/usr/local/bin/monitor-mysql) ERROR (getpwnam() failed)
```
The error was because no user was specified in the cronjob. When you use cronjob in file /etc/crontab, you need to specify the username before the command in cronhjob.

On the server, I had the following cronjob
```
*/5 * * * * /usr/local/bin/monitor-mysql > /var/log/mysql-monitor.log
```
To fix the error, I added the user name before the command as below.
```
*/5 * * * * root /usr/local/bin/monitor-mysql > /var/log/mysql-monitor.log
```
See cronjob
October 29, 2022
Run rsync if not running using cronjob
I want to rsync files from one server to another server every 5 minutes, but only want to start the rsync if the previous rsync command has finished. Time for one rsync depends on how much data changed on the source server, so the time taken to finish rsync cronjob varies.

Create file rsync.sh
```
#!/bin/bash

if ! pgrep -x "rsync" > /dev/null
then
    rsync -avzP /var/www/html/files/  [email protected]:/var/www/html/files/
fi
```
Set cronjob like
```
*/10 * * * * /root/rsync.sh > /dev/null
```
January 23, 2022
How to Enable Magento 2 Cronjob
Magento uses cron jobs for numerous features to schedule activities. To enable the cron job in Magento 2, log in to the server using SSH. Switch to the appropriate user if you are logged in as root. Now run command
```
php bin/magento cron:install
```
If you need to remove the cronjob, run
```
php bin/magento cron:remove
```
See Magento
August 11, 2021

Set vim as default cronjob editor

Method 1

vi /etc/bashrc

Find

export EDITOR="pico"
export VISUAL="pico"

Replace with

export EDITOR="vi"
export VISUAL="vi"

Method 2

edit .bash_profile

vi /root/.bash_profile

Add

export VISUAL=vi

Once added, .bash_profile will look like

root@server54 [~]# cat .bash_profile
# .bash_profile

# Get the aliases and functions
if [ -f ~/.bashrc ]; then
        . ~/.bashrc
fi

# User specific environment and startup programs

PATH=$PATH:$HOME/bin

export VISUAL=vi
export PATH
unset USERNAME
uptime
root@server54 [~]#

Method 3

If you need it done one time only, run following commands on command prompt.

VISUAL=vi; export VISUAL

August 30, 2020

Start a program after reboot using cronjob
To start a program using cronjob, create a cronjob like
```
@reboot /root/start.sh
```
On system boot, the command “/root/start.sh” will be executed.
July 20, 2018

cronjob

crontab
Start a program after reboot using cronjob
Running wp-cron with cronjob
Cronjob for Magento 1.9
set vi as default cronjob editor
Cron Job fails with Error Message “(getpwnam() failed): No such file or directory”

Cronjob Timing

* * * * *  = every minute
*/5 * * * *  = every 5 minute
0 * * * *  = every hour
0 * * * *  = every day at 00:00 hour.
0 0 * * 0  = every Sunday at 0 minutes, 0 hour.

Here is how it works.

# Example of job definition:
# .---------------- minute (0 - 59)
# |  .------------- hour (0 - 23)
# |  |  .---------- day of month (1 - 31)
# |  |  |  .------- month (1 - 12) OR jan,feb,mar,apr ...
# |  |  |  |  .---- day of week (0 - 6) (Sunday=0 or 7) OR sun,mon,tue,wed,thu,fri,sat
# |  |  |  |  |
# *  *  *  *  * user-name  command to be executed

Disable cronjob output

To disable cronjob output, add the following to the end of the script

 > /dev/null 2>&1

 1> /dev/null 2> /dev/null

Save cronjob result to file

To save the result of a cronjob to a file, use

20 5 * * * /bin/bash /usr/serverok/mysqldb-backup.sh > /var/log/mysqldb-backup.log 2>&1

List all cronjobs

To list all cronjob, run

crontab -l

To edit all cronjobs, run

crontab -e

December 22, 2017