Re: Help with script - doesn't work properly from cron
On Fri, Jul 17, 2009 at 02:53:21PM -0700, Erik Olof Wahlstrom wrote:
#!/bin/bash
BACKUP_DIR=/media/disk/AUTOMATED_BACKUPS/DB_DAILY
CURRENT_DIR=$BACKUP_DIR/`date +%d`
# See how you call date here without an explicit path? That's good.
DATABASES=$(/usr/bin/mysql -uUsername -pPassword -Bse 'show databases')
echo 'Backing up databases: '$DATABASES
echo Backing up databases: $DATABASES
if [ -e $CURRENT_DIR ]
if [ -d $CURRENT_DIR ]
# Of course, if it's a file, you would have problems below
then
cd $CURRENT_DIR
/bin/rm *
cd $CURRENT_DIR || exit 1
rm -f *
# NEVER do rm * after a cd without checking that the cd
# succeeded!
# You don't need an explicit path on rm. You didn't need one
# on date, so why put one on rm?
# In this particular version of this particular script, you can
# get away with not quoting the $CURRENT_DIR parameter expansion,
# but quoting it will save your butt if someone changes it, e.g.:
# CURRENT_DIR='/media/disk/c/Program Files'
else
/bin/mkdir $CURRENT_DIR
mkdir -p $CURRENT_DIR
cd $CURRENT_DIR
cd $CURRENT_DIR || exit 1
fi
for DB in $DATABASES
do
/usr/bin/mysqldump -uroot -pHardAsMySql321 $DB | bzip2
$DB_`date +%Y-%m-%d_%k.%M`.sql.bz2
# Long line, probably broken by your mailer. For clarity, I'd
# write it on two lines explicitily:
mysqldump -uroot -pHardAsMySql321 $DB |
bzip2 ${DB}_$(date +%Y-%m-%d_%k.%M).sql.bz2
done
exit 0
Can any skilled eyes see why this doesn't work when it is run from the roots
crontab?
None of the changes I suggested should really affect that. Perhaps it's
some sort of mysql-specific thing?
Additionally, when I run the script as root in the terminal, I get the
following output:
Backing up databases: information_schema db1 db2 db3
/bin/rm: cannot remove `*': No such file or directory
The rm -f will suppress that error message.
Is there a better way to clear out last months files before making the
current backups?
You could also consider writing it this way:
cd /
rm -rf $CURRENT_DIR
mkdir -p $CURRENT_DIR
cd $CURRENT_DIR || exit 1
Then you don't even need to check whether it already exists.
On Sat, Jul 18, 2009 at 11:25:13AM +0200, Bernd Eggink wrote:
You could replace the whole if-then-else clause by
mkdir -p $CURRENT_DIR
cd $CURRENT_DIR
rm -f *
Another failure to check the results of cd before doing rm *. This
can and will lead to disasters.
Re: Help with script - doesn't work properly from cron
Greg Wooledge wrote:
Erik Olof Wahlstrom wrote:
/usr/bin/mysqldump -uroot -pHardAsMySql321 $DB | bzip2
$DB_`date +%Y-%m-%d_%k.%M`.sql.bz2
# Long line, probably broken by your mailer. For clarity, I'd
# write it on two lines explicitily:
mysqldump -uroot -pHardAsMySql321 $DB |
bzip2 ${DB}_$(date +%Y-%m-%d_%k.%M).sql.bz2
You might want to set umask restrictive so that the backup file
created by the redirection isn't world readable.
umask 077
I have never liked whitespace in filenames and %k may produce spaces
in filenames. Better IMNHO to use %H here and avoid the space. Why
use a dot instead of the more common colon in the time?
mysqldump -uroot -pHardAsMySql321 $DB |
bzip2 ${DB}_$(date +%Y-%m-%d_%H:%M).sql.bz2
You could also consider writing it this way:
cd /
rm -rf $CURRENT_DIR
mkdir -p $CURRENT_DIR
cd $CURRENT_DIR || exit 1
Then you don't even need to check whether it already exists.
Why bother changing directory there at all? :-)
mysqldump -uroot -pHardAsMySql321 $DB |
bzip2 $CURRENT_DIR/${DB}_$(date +%Y-%m-%d_%H:%M).sql.bz2
Bernd Eggink wrote:
You could replace the whole if-then-else clause by
mkdir -p $CURRENT_DIR
cd $CURRENT_DIR
rm -f *
Another failure to check the results of cd before doing rm *. This
can and will lead to disasters.
Doing 'rm *' just makes me extremely nervous even when care is taken
to ensure that it is going to work okay. I think it is safer to avoid
it. Let me suggest the following:
CURRENT_DIR=$BACKUP_DIR/`date +%d`
...
cd $CURRENT_DIR || exit 1
...
mysqldump -uroot -pHardAsMySql321 $DB |
bzip2 ${DB}_$(date +%Y-%m-%d_%k.%M).sql.bz2
In this case the file name is going to be SOMETHING.sql.bz2. Instead
of using 'rm *' it would make me much less nervous to qualify that
file glob with 'rm -f *.sql.bz2' at least so that if this were to escape
and be invoked elsewhere it would have limited damage potential.
cd $CURRENT_DIR || exit 1
rm -f *.sql.bz2
Is there a better way to clear out last months files before making the
current backups?
Personally I have the following line in my /etc/cron.d/local-mysql
crontab. The 'savelog' command with -c7 will save seven days of
datestamped backups (sufficient for my case) without further code.
That could easily be -c30 to save 30 days worth. The 'savelog'
command pretty much handles all of your issues with datestamping and
cycling files very easily.
30 3 * * * root umask 077 ; mysqldump --defaults-file=/etc/mysql/debian.cnf
--all-databases | gzip /var/backups/mysql.dump ; savelog -q -d -l -C -c7
/var/backups/mysql.dump
Bob
Re: Help with script - doesn't work properly from cron
Thanks everyone for your pointers - I ended up with this:
#!/bin/bash
BACKUP_DIR=/media/disk/AUTOMATED_BACKUPS/DB_DAILY
CURRENT_DIR=$BACKUP_DIR/`date +%d`
DATABASES=$(mysql -uroot -pNewSecretPw -Bse 'show databases')
echo 'Backing up databases: '$DATABASES
cd /
rm -rf $CURRENT_DIR
mkdir -p $CURRENT_DIR
cd $CURRENT_DIR || exit 1
for DB in $DATABASES
do
mysqldump -uroot -pNewSecretPw $DB | bzip2 ${DB}_$(date
+%Y-%m-%d_%H:%M).sql.bz2
done
exit 0
It worked on the first manual run - keeping my fingers crossed for tonight!
:-P
Bob Proulx wrote:
Greg Wooledge wrote:
Erik Olof Wahlstrom wrote:
/usr/bin/mysqldump -uroot -pHardAsMySql321 $DB | bzip2
$DB_`date +%Y-%m-%d_%k.%M`.sql.bz2
# Long line, probably broken by your mailer. For clarity, I'd
# write it on two lines explicitily:
mysqldump -uroot -pHardAsMySql321 $DB |
bzip2 ${DB}_$(date +%Y-%m-%d_%k.%M).sql.bz2
You might want to set umask restrictive so that the backup file
created by the redirection isn't world readable.
umask 077
I have never liked whitespace in filenames and %k may produce spaces
in filenames. Better IMNHO to use %H here and avoid the space. Why
use a dot instead of the more common colon in the time?
mysqldump -uroot -pHardAsMySql321 $DB |
bzip2 ${DB}_$(date +%Y-%m-%d_%H:%M).sql.bz2
You could also consider writing it this way:
cd /
rm -rf $CURRENT_DIR
mkdir -p $CURRENT_DIR
cd $CURRENT_DIR || exit 1
Then you don't even need to check whether it already exists.
Why bother changing directory there at all? :-)
mysqldump -uroot -pHardAsMySql321 $DB |
bzip2 $CURRENT_DIR/${DB}_$(date +%Y-%m-%d_%H:%M).sql.bz2
Bernd Eggink wrote:
You could replace the whole if-then-else clause by
mkdir -p $CURRENT_DIR
cd $CURRENT_DIR
rm -f *
Another failure to check the results of cd before doing rm *. This
can and will lead to disasters.
Doing 'rm *' just makes me extremely nervous even when care is taken
to ensure that it is going to work okay. I think it is safer to avoid
it. Let me suggest the following:
CURRENT_DIR=$BACKUP_DIR/`date +%d`
...
cd $CURRENT_DIR || exit 1
...
mysqldump -uroot -pHardAsMySql321 $DB |
bzip2 ${DB}_$(date +%Y-%m-%d_%k.%M).sql.bz2
In this case the file name is going to be SOMETHING.sql.bz2. Instead
of using 'rm *' it would make me much less nervous to qualify that
file glob with 'rm -f *.sql.bz2' at least so that if this were to escape
and be invoked elsewhere it would have limited damage potential.
cd $CURRENT_DIR || exit 1
rm -f *.sql.bz2
Is there a better way to clear out last months files before making the
current backups?
Personally I have the following line in my /etc/cron.d/local-mysql
crontab. The 'savelog' command with -c7 will save seven days of
datestamped backups (sufficient for my case) without further code.
That could easily be -c30 to save 30 days worth. The 'savelog'
command pretty much handles all of your issues with datestamping and
cycling files very easily.
30 3 * * * root umask 077 ; mysqldump
--defaults-file=/etc/mysql/debian.cnf --all-databases | gzip
/var/backups/mysql.dump ; savelog -q -d -l -C -c7 /var/backups/mysql.dump
Bob
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Re: Help with script - doesn't work properly from cron
Erik Olof Wahlstrom schrieb: Hello - I am having a problem with a backup script that I have put together - when I run it as root from the terminal, it works as expected (with one caveat); however, when cron runs it, the daily backup folder is created but no files are deposited into that folder... Here is the script: #!/bin/bash BACKUP_DIR=/media/disk/AUTOMATED_BACKUPS/DB_DAILY CURRENT_DIR=$BACKUP_DIR/`date +%d` DATABASES=$(/usr/bin/mysql -uUsername -pPassword -Bse 'show databases') echo 'Backing up databases: '$DATABASES if [ -e $CURRENT_DIR ] then cd $CURRENT_DIR /bin/rm * else /bin/mkdir $CURRENT_DIR cd $CURRENT_DIR fi for DB in $DATABASES do /usr/bin/mysqldump -uroot -pHardAsMySql321 $DB | bzip2 $DB_`date +%Y-%m-%d_%k.%M`.sql.bz2 done exit 0 Can any skilled eyes see why this doesn't work when it is run from the roots crontab? The reason may be that crontab commands are run with /bin/sh -c command (Bourne shell mode). Try changing the crontab entry to /bin/bash command. Additionally, when I run the script as root in the terminal, I get the following output: Backing up databases: information_schema db1 db2 db3 /bin/rm: cannot remove `*': No such file or directory Is there a better way to clear out last months files before making the current backups? You could replace the whole if-then-else clause by mkdir -p $CURRENT_DIR cd $CURRENT_DIR rm -f * provided the options are supported on your system. Regards, Bernd -- Bernd Eggink http://sudrala.de
