Including Cron/Crontab in my Bash Backup Script with inputs - linux

Im doing a Bash-Backup Script with 3 Options:
Do fullbackup
Do fullbackup at a specific time with cron
First I want to ask for the path like: Path of directory: /home
Then i want the hour for the backup: Hour for the backup (0:00-23:59) : 2:00
Then a simple question like: The backup will execute at 2:00. Do you agree(y/n)
I know how to do a crontab but I have no idea how to include that in my script so that I choose option 2 and then the script asks me for the directory and time and set then the crontab.
Any ideas or help would be appreciated!

You can get the existing crontab with
crontab -l
and install a new crontab with
crontab file
So your script would probably need something like
crontab -l | grep -v "# install-backup-script" > /tmp/file.$$
echo "$min $hour * * * /full/path/to/script # install-backup-script" >> /tmp/file.$$
crontab /tmp/file.$$
rm -f /tmp/file.$$

Related

Concatenate file output text with Crontab

I have followed up this question successfully, Using CRON jobs to visit url?, to maintain the following Cron task:
*/30 * * * * wget -O - https://example.com/operation/lazy-actions?lt=SOME_ACCESS_TOKEN_HERE >/dev/null 2>&1
The above Cron task works fine and it visits the URL periodically every 30 minutes.
However, the access token is recorded in a text file found in /home/myaccount/www/site/aToken.txt, the aToken file is very simple text file of one line which just contains the token string.
I have tried to read its contents and pass, using cat, it to the crontab command like the following:
*/30 * * * * wget -O - https://example.com/operation/lazy-actions?lt=|cat /home/myaccount/www/site/aToken.txt| >/dev/null 2>&1
However, the above solution has been failed to run the cronjob.
I edit Cronjobs using crontab -e using nano on Ubuntu 16.04
This is a quick solution that will do exactly what you want without the complicated one-liner:
Create this file in your myaccount -- You may also put it into your bin directory if you so desire just remember where you put it so you can call it from your CRON. Also make sure the user has permissions to read/write to the directory the sh file is in
wget.sh
#!/bin/bash
#simple cd -- change directory
cd /home/myaccount/www/site/
#grab token into variable aToken
aToken=`cat aToken.txt`
#simple cd -- move to wget directory
cd /wherever/you/want/the/wget/results/saved
#Notice the $ -- This is how we let the shell know that aToken is a variable = $aToken
#wget -O - https://example.com/operation/lazy-actions?lt=$aToken
wget -q -nv -O /tmp/wget.txt https://example.com/operation/lazy-actions?lt=$aToken >/dev/null 2>/dev/null
# You can writle logs etc etc afterward here. IE
echo "Job was successful" >> /dir/to/logs/success.log
Then simply call this file with your CRON like you are doing already.
*/30 * * * * sh /home/myaccount/www/site/wget.sh >/dev/null 2>&1
Built on that question, Concatenate in bash the output of two commands without newline character, I have got the following simple solution:
wget -O - https://example.com/operation/lazy-actions?lt="$(cat /home/myaccount/www/site/aToken.txt)" >/dev/null 2>&1
Where it able to read the contents of the text file and then echoed to the command stream.

sh file not running on cron ubuntu

I am trying to run a shell script on crontab on Ubuntu platform. I have tried googling and other links but nothing has helped so far.
This is my crontab:
*/2 * * * * sudo bash /data/html/mysite/site_cleanup.sh
This is the content of my sh file:
#!/bin/sh
# How many days retention do we want ?
DAYS=0
# geting present day
now=$(date +"%m_%d_%Y")
# Where is the base directory
BASEDIR=/data/html/mysite
#where is the backup directory
BKPDIR=/data/html/backup
# Where is the log file
LOGFILE=$BKPDIR/log/mysite.log
# add to tar
tar -cvzf $now.tar.gz $BASEDIR
mv $now.tar.gz $BKPDIR
# REMOVE OLD FILES
echo `date` Purge Started >> $LOGFILE
find $BASEDIR -mtime +$DAYS | xargs rm
echo `date` Purge Completed >> $LOGFILE
The same script runs from a terminal and gives the desired result.
Generic troubleshooting for noninteractive shell scripts
Put set -x; exec 2>/path/to/logfile at the top of your script to log all subsequent commands to a file as they're run. If this doesn't work, you'll know that your script isn't being run at all; if it does, you'll know where it fails and how.
If this is a personal crontab
If you're running crontab -e as a user (without sudo), then the crontab being modified is one for commands run with that user's permissions. Check that file permissions allow that user to modify the content in question (which, if these files are in a cgi-bin directory, may require being run by the same user as the web server).
If your intent is to have commands run as root, rather than as your own user, be sure you use sudo when editing the crontab to edit the system crontab instead (but please take care as to your script's correctness in this case -- carelessness such as missing quotes or lack of appropriate precautions in xargs usage can cause a script to delete the wrong files if malicious filenames are created):
sudo crontab -e ## to edit the system (root) crontab
...or, if you're cleaning up files owned by the apache user (for example; check which account is correct for your own operating system and web server):
sudo -u apache crontab -e ## to edit the apache user's crontab
Troubleshooting for a system crontab
Do not attempt to put a sudo command within the commands run by cron; with sudo's default configuration, it requires a TTY (a keyboard and screen) to be attached to a session in order to run. Thus, your crontab line should not contain sudo, but instead should look like the following:
*/2 * * * * bash /data/html/mysite/site_cleanup.sh
Your issue is likely coming from the sudo call from your user level cron. Unless you've gone through and edited the bashrc profile to allow that script to run without sudo it'll hang up every time.
So you can lookup how to run a script with no password by modifying the bashrc profile, remove the sudo call if you aren't doing something in your script that calls for Super User permissions, or as a last ditch, extremely bad idea you can call your script from root's cron by doing sudo crontab -e or sudo env EDITOR=nano crontab -e if you prefer nano as your editor.
try to add this line to the crontab of user root and without the sudo.
like this:
*/2 * * * * bash /data/html/mysite/site_cleanup.sh

How to schedule two separate crontabs

It supposed to be simple, but I must be missing something.
deletelogs file:
0 11 * * 6 ./scripts/deletelogs.sh
backupstuff file:
0 23 * * * ./scripts/backupstuff.sh
crontab -l shows the deletelogs job
If I do crontab backupstuff, then crontab -l shows the backupstuff job.
How can I schedule both, Why can't I list both with crontab -l?
The crontab file can read a set of entries from a file named on its command line:
crontab filename
or from standard input:
echo ... | crontab
Both commands replace the entire crontab.
To combine two input files:
cat file1 file2 | crontab
To add the contents of a file to an existing crontab:
( crontab -l ; cat file ) | crontab
Personally, I keep my entire crontab in a single file, installed with a simple crontab filename; I keep that file under a source control system so I can restore it if I make a mistake. But if you have a need to split it into multiple files, you can do that.

rdiff-backup bash script and cron trouble

I have this very simple bash script:
#!/opt/bin/bash
/opt/bin/rdiff-backup --force --print-statistics myhost::/var/bkp /volume1/backups/sql 2>&1 > /var/log/rdiff-backup.log;
/opt/bin/rdiff-backup --force --print-statistics myhost::/var/www/vhosts /volume1/backups/vhosts 2>&1 >> /var/log/rdiff-backup.log;
/opt/bin/rdiff-backup --force --print-statistics myhost::/etc /volume1/backups/etc 2>&1 >> /var/log/rdiff-backup.log;
/opt/bin/rdiff-backup --force --print-statistics /volume1/homes /volume1/backups/homes 2>&1 >> /var/log/rdiff-backup.log;
cat /var/log/rdiff-backup.log | /opt/bin/nail -s "rdiff-backup log" me#email.com;
if I run the script from the command line, in this way:
nohup /path/to/my/scipt.sh &
it works fine, appending each rdiff-backup statistic report to the rdiff-backup.log and sending this file to my email address, as expected. But if I put the script in the crontab, the script make only one rdiff-backup job sending statistics via email. I cannot understand because the script doesn't work in the same way...
Any idea?
this is my cronjob entry:
30 19 * * * /opt/bin/bash /volume1/backups/backup.sh
via crontab only the last job is executed correctly, I think because this is the only one local backup. When I execute the script from command line I use the root user, and the public key of the root user is in the /root/./ssh/authorized_keys of the remote machine. The owner of the crontab file is the root user too, I created them through "crontab -e" using the root account.
First of all you need to make sure the script used in cron doesn't output anything, otherwise:
cron will assume there is an error
you will not see the error if any
A solution for this is to use
30 19 * * * /opt/bin/bash /volume1/backups/backup.sh 2>&1 >> /var/log/rdiff-backup-cron.log;
Second of all, it appears you are losing env variables when executing via cron, try adding the env settings to your script
#!/opt/bin/bash
. /root/.profile
/opt/bin/rdiff-backup --force --print-statistics myhost::/var/bkp /volume1/backups/sql 2>&1 > /var/log/rdiff-backup.log
if /root/.profile doesn't, exist try adding . /root/.bashrc or /etc/profile
I hope this helps.

Crontab without crontab -e

I would like to add a crontab schedule by doing this in my server:
echo "30 * * * * /home/my/var/dir/to/script /var/etc/etc/etc/" > crontab -e
Is there a way to do this without going doing crontab -e and then typing in the command?
Could try
1)nano /etc/crontab (or any other editor, e.g. emacs)
2)echo "30 * * * * /home/my/var/dir/to/script /var/etc/etc/etc/" > /etc/crontab
3)or put the contents of this into a file, then do "file > /etc/crontab"
like root:
echo "30 * * * * /home/my/var/dir/to/script /var/etc/etc/etc/" > /var/spool/cron/crontabs/username
We have the following setup in production on RHEL:
- a custom software starting sh in init.d , which
- handles cron start , stop , reload
- writes cron tasks into separate tmp file and loads this file with crontab -e
I have been only maintaining it for several months but it works like a charm ...
The proper fix is probably to use a file as specified in https://stackoverflow.com/a/4421284/377927, but it is possible to use tee to append a line to the crontab by doing e.g.:
echo "* * * * * ls" | EDITOR="tee -a" crontab -e
tee -a will append stdin to the file it gets specfied, the EDITOR variable tells crontab to use tee -a as editor.
If you have the whole crontab in a text file, you can upload a whole crontab to replace the old crontab by doing:
cat <crontab_text_file> | crontab -
This will wipe out your old crontab. Using '-' allows you to use standard input into the crontab.

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