[Koha] How to run cron to autobackup of koha database (only sql) ?

[SATISH]

Dear All,

I have two questions regarding 1) cronjob and 2) time stamp

I would like to know, How to setup cronjob to autobackup of database sql
daily ?(before we close the library)

Till now, I have enabled Cronjob  with

localhost:~# cd /usr/share/koha/bin/cronjobs
localhost:~# crontab -u root crontab.example

/usr/share/koha/bin/cronjobs shows -  crontab.example and it has all the
required instructions for the cron.

I wanted to autobackup of koha db (example: at 5:15 pm daily before library
closes)
I tried with, following steps.

1. added in crontab -e
#ADDED BY SATISH FOR DAILY BACKUP AT 5.15 PM DAILY
15 17 * * *  mysqldump -uroot -pmysqlrootpassword dbname | gzip -9 >
/home/satish/Dropbox/dbname.sql.gz

When I check the dbsize, it is "zero". Therefore, It is not working!

2. by default Koha has  /etc/cron.daily
koha-run-backups --days 2 --output /var/spool/koha
But, It backups when system boots every morning.
how to schedule the time for the same?
And Koha-run-backups has all the sql and config files backup. But I wanted
have only complete db (sql).

And also, our library works from 9:30 am to 5.30 pm on week days and
9:30-1:30 pm on every Saturday. (Desktop machine) as server, will be
shutdown in the evening everyday until library receives a dedicated server
machine.

Currently, after setting up- Postfix mail agent, overdue message, advance
due notice, check in, check out , new registration  notice all are working
fine,. but I wanted to setup timings as per the open and closing hours.

The checkout Message includes (Notices Section):
example Due Date: 20/09/2016 23:59
How to change the Due Date time from 23:59 to 5.30 pm or 17:30 ?

My Koha Details are:
Version -16.5.01 (upgraded from 3.16.00)
OS: Ubuntu - 14.04 server edition (upgraded from 12.04)
Install method - Packages

Kindly share your best practices?

with thanks
Satish MV
Librarian
Govt. Engineering College, Hassan
Karnataka.

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