[rt-users] mysqldump refusing to finish

[Ole Craig]

On Wed, 2006-06-07 at 08:37 +0930, Luke Vanderfluit wrote:
> Hi.
> 
> I have a cron job that does a database backup for RT.
> That backup is currently failing with the following error:
> 
> mysqldump: Error 2020: Got packet bigger than 'max_allowed_packet' bytes when dumping table `Attachments` at row: 1784599
> 
> My mysqldump command looks like this:
> 
> /usr/local/mysql/bin/mysqldump --opt --skip-extended-insert 
> --skip-lock-tables --single-transaction --complete-insert 
> --max_allowed_packet=32M rt3 | bzip2 -9 > rt3.out-`date +\%Y\%m\%d-\%H`.bz2

recent mysqldump versions do some funky things with combining insert
statements. Your "--max_allowed_packet=32M" should match what you have
defined for that variable in /etc/my.cnf, and to be on the safe side I'd
check that your running mysql instance is using the value you think it
is:

mysql rt3 -e 'show variables;' | grep max_allowed_packet

...and I'd also add the following to your mysqldump command:

-O net_buffer_length=32M

	(presuming that your max_allowed_packet size is actually 32M. I thought
the ceiling was 16M, but I'm no mysql DBA.)

 
-- 
/Ole Craig
Security Engineer

303-381-3802 (main support hotline)
303-381-3824 (my direct line)
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