I've seen this post to re-synchronize a slave database when only one slave is connected to a master DB.
If I understood well, this solution is not the best when we need to resynchronize only 1 slave DB out of batch of slave DBs.
Is there a way to do this, without having to resynchronize all the slave DBs connected to the master ?
I guess the RESET MASTER would affect all the slave DBs state and would lead to resynchronize all of them.
Thank you for your help
Cheers
I found the solution using these mysqldump option to avoid using RESET MASTER way :
mysqldump -p --skip-lock-tables --single-transaction --flush-logs --hex-blob --master-data=2 <dbname> > /tmp/<dbname>.sql
This way, the master log bin and position are not changed, but just added on top of the file .sql.
If you set master-data=2 they will be commented in the file
If you set master-data=1 they will not be commented in the file
Once your dump is on your slave host you can reset the slave, import your dump and then run the mysql command change master to MASTER_LOG_FILE='mysqld-bin.xxxxxxx',MASTER_LOG_POS=xxxx; with the values indicated in the top of your dump file.
Cheers
What in that case with rest of your DBs? If you change binlog and position will they be up to date?
Regards
Robert
I have a root access to a mysql server, I need to dump ALL the database inside the server.
I tried with a simple mysqldump, but the server and pc seems blocked due to the large size of the databases and tables. Can I "optimize" this DUMP avoiding locking the server (and PC) ?
Thank you so much!
EDIT:
I want to EXPORT all the databases from a Mysql Server.
I need to understand what options to pass to mysqldump to avoid blocking:
The Mysql Server <---- it CAN'T go down
The PC that is goind to do this DUMP
You can disable locking:
mysqldump --skip-lock-tables
Of course you will not be able to create a consistent dump that way, so I would not recommend to use that option.
When only using MyISAM and ARCHIVE tables you might want to consider using mysqlhotcopy (included with a regular mysql package). There is similar software for other table engines like InnoDB available.
Another option is using a replication slave for backup.
Fire the dump command from commandline. :
mysqldump <other mysqldump options> --routines > outputfile.sql
If we want to backup ONLY the stored procedures and triggers and not the mysql tables and data then we should run something like:
mysqldump --routines --no-create-info --no-data --no-create-db --skip-opt <database> > outputfile.sql
If you need to import them to another db/server you will have to run something like:
mysql <database> < outputfile.sql
Trying to find out how people do a full backup/restore procedure: The user defined database schema and data can be easily backed up via mysqldump, but what about the master tables and data? i.e. if the server goes completely bananas, how can I rebuild the database, i.e. including all the settings in Mysql? is it just a matter of dumping/importing the information_schema and mysql databases + restore my.cnf ? (innodb or MyISAM, not ISAM)
--
edit: Thanks!
You don't back up information_schema, but otherwise, yes, keep a copy of your my.cnf and a dump of the mysql db tables and log settings. To do this do:
mysqldump -u$user -p$pass --all-databases > db_backup.sql
If you're going to restore to the 100% same version of MySQL, you could also backup by shutting down your server and doing a full copy of the contents of /var/lib/mysql (or wherever your data files are) along with your my.cnf file. Then just drop the copy back in place when you want to go live and turn on your server.
I need to backup the whole of a MySQL database with the information about all users and their permissions and passwords.
I see the options on http://www.igvita.com/2007/10/10/hands-on-mysql-backup-migration/,
but what should be the options to backup all of the MySQL database with all users and passwords and permissions and all database data?
Just a full backup of MySQL so I can import later on another machine.
At it's most basic, the mysqldump command you can use is:
mysqldump -u$user -p$pass -S $socket --all-databases > db_backup.sql
That will include the mysql database, which will have all the users/privs tables.
There are drawbacks to running this on a production system as it can cause locking. If your tables are small enough, it may not have a significant impact. You will want to test it first.
However, if you are running a pure InnoDB environment, you can use the --single-transaction flag which will create the dump in a single transaction (get it) thus preventing locking on the database. Note, there are corner cases where the initial FLUSH TABLES command run by the dump can lock the tables. If that is the case, kill the dump and restart it. I would also recommend that if you are using this for backup purposes, use the --master-data flag as well to get the binary log coordinates from where the dump was taken. That way, if you need to restore, you can import the dump file and then use the mysqlbinlog command to replay the binary log files from the position where this dump was taken.
If you'd like to transfer also stored procedures and triggers it's may be worth to use
mysqldump --all-databases --routines --triggers
if you have master/slave replication you may dump their settings
--dump-slave and/or --master-data
Oneliner suitable for daily backups of all your databases:
mysqldump -u root -pVeryStrongPassword --all-databases | gzip -9 > ./DBBackup.$(date +"%d.%m.%Y").sql.gz
If put in cron it will create files in format DBBackup.09.07.2022.sql.gz on a daily basis.
I want to copy a live production database into my local development database. Is there a way to do this without locking the production database?
I'm currently using:
mysqldump -u root --password=xxx -h xxx my_db1 | mysql -u root --password=xxx -h localhost my_db1
But it's locking each table as it runs.
Does the --lock-tables=false option work?
According to the man page, if you are dumping InnoDB tables you can use the --single-transaction option:
--lock-tables, -l
Lock all tables before dumping them. The tables are locked with READ
LOCAL to allow concurrent inserts in the case of MyISAM tables. For
transactional tables such as InnoDB and BDB, --single-transaction is
a much better option, because it does not need to lock the tables at
all.
For innodb DB:
mysqldump --single-transaction=TRUE -u username -p DB
This is ages too late, but good for anyone that is searching the topic. If you're not innoDB, and you're not worried about locking while you dump simply use the option:
--lock-tables=false
The answer varies depending on what storage engine you're using. The ideal scenario is if you're using InnoDB. In that case you can use the --single-transaction flag, which will give you a coherent snapshot of the database at the time that the dump begins.
--skip-add-locks helped for me
To dump large tables, you should combine the --single-transaction option with --quick.
http://dev.mysql.com/doc/refman/5.1/en/mysqldump.html#option_mysqldump_single-transaction
This is about as late compared to the guy who said he was late as he was to the original answer, but in my case (MySQL via WAMP on Windows 7), I had to use:
--skip-lock-tables
For InnoDB tables use flag --single-transaction
it dumps the consistent state of the database at the time when BEGIN
was issued without blocking any applications
MySQL DOCS
http://dev.mysql.com/doc/refman/5.1/en/mysqldump.html#option_mysqldump_single-transaction
Honestly, I would setup replication for this, as if you don't lock tables you will get inconsistent data out of the dump.
If the dump takes longer time, tables which were already dumped might have changed along with some table which is only about to be dumped.
So either lock the tables or use replication.
mysqldump -uuid -ppwd --skip-opt --single-transaction --max_allowed_packet=1G -q db | mysql -u root --password=xxx -h localhost db
When using MySQL Workbench, at Data Export, click in Advanced Options and uncheck the "lock-tables" options.
Due to https://dev.mysql.com/doc/refman/5.7/en/mysqldump.html#option_mysqldump_lock-tables :
Some options, such as --opt (which is enabled by default), automatically enable --lock-tables. If you want to override this, use --skip-lock-tables at the end of the option list.
If you use the Percona XtraDB Cluster -
I found that adding
--skip-add-locks
to the mysqldump command
Allows the Percona XtraDB Cluster to run the dump file
without an issue about LOCK TABLES commands in the dump file.
Another late answer:
If you are trying to make a hot copy of server database (in a linux environment) and the database engine of all tables is MyISAM you should use mysqlhotcopy.
Acordingly to documentation:
It uses FLUSH TABLES, LOCK TABLES, and cp or scp to make a database
backup. It is a fast way to make a backup of the database or single
tables, but it can be run only on the same machine where the database
directories are located. mysqlhotcopy works only for backing up
MyISAM and ARCHIVE tables.
The LOCK TABLES time depends of the time the server can copy MySQL files (it doesn't make a dump).
As none of these approaches worked for me, I simply did a:
mysqldump [...] | grep -v "LOCK TABLE" | mysql [...]
It will exclude both LOCK TABLE <x> and UNLOCK TABLES commands.
Note: Hopefully your data doesn't contain that string in it!