I put the percona toolkit onto my DB hosts so I could try and deal with a problem with mysql going silently out of sync. That is replication seems fine on all nodes. Slave IO running / Slave SQL running and 0 seconds behind master.
I have 4 dbs setup in master/master on the first two, and two slaves, I'm using MariaDB-server-10.0.21 for the MySQL database on each node.
Yet the content of the wiki I run on them seems to go out of sync even with those positive indicators. For instance, you'll create a page, save it, get the thumbs up from the wiki. Then reload the page and the content will be gone! Then you point the wiki config to look at each db one at a time, reload the page. Until you find the db that saved the changes you made.
Then dump that db, stop the slaves on each host one at time and then import that version of the database. It's a real pain!
So I installed the percona toolkit after reading an article on how to solve this problem.
And when I run the pt-table-checksum command I get this error, saying Replication filters are set on these hosts:
[root#db1:~] #pt-table-checksum --replicate=test.checksum --databases=sean --ignore-tables=semaphore localhost
10-17T00:31:11 Replication filters are set on these hosts:
db3
binlog_do_db = jfwiki,jokefire,bacula,mysql
db2
binlog_do_db = jfwiki,jokefire,bacula,mysql
db4
binlog_do_db = jfwiki,jokefire,bacula,mysql
Please read the --check-replication-filters documentation to learn how to solve this problem. at /bin/pt-table-checksum line 9644.
But that EC2 host it claims that it's having trouble contacting equates to my 4th database host. I found out by ssh'ing in as my user to that DNS address. And I have no trouble at all logging into that host on the command line using mysql:
Can someone please explain what does this error mean, and how can I fix the issue? Is there any general advice you can give for mysql replication falling silently out of sync?
Thanks
Some of the pt tools need to create their own database and have it replicated. Your binlog_do_db prevents the extra db from being replicated, hence preventing that tool from working.
While you have the binlog_do removed, see what db it being built. Then add it.
Related
I am having a difficult time in setting Master-Slave configuration.
Master Database runs on Ubuntu( Amazon AWS instance) and successfully set-up master replication.
I have localhost as a Slave Server. (Windows Machine).
Snapshot of Master Database
Master database has record
Binar Log Information
Process List on Master Replication
Status of Master Replication
I debug master replication which works okay I guess.
On the Salve Side:
Status on Slave Side
Even though MASTER_LOG and MASTER_POS are synced but data doesn't.
Currently, I have 0 table on Slave side and 34 tables on Master side.
Tables on Slave side
I am open to any suggestion or any reference do you have.
I spend an entire day and trying to find what I did wrong.
I want to Sync my Local database with a database hosted on remote-server.
Update: Thigs I did to debug the Master-Slave Replication
Checked Master Database is up and running.
Master Status and Connected Slaves. [Which includes unique id for
each server.]
Slave database is up and running [Including Slave IO Thread and
SQL thread is running.]
These three steps ensure that Master-Slave replication is up and running without any problem.
Handling Data Sync Problem
Created/update/delete data in the master database to check
whether data is sync on a server or not.
Checked Binary Log [Specifically I checked the file size. If I
entered data file size will continuously increasing.]
Thanks in advance.
we had similar problem - read more about gotchas in "binlog-do-db" and "replication-do-db" and related parameters. Here is a big problem with crossdatabase references. At the and we had to remove these settings limiting replication.
Why MySQL’s binlog-do-db option is dangerous
Gotchas in MySQL replication
As your show slave status output says you enabled Replicate_DO_DB for the DB "Arihantpos" at the same time you did Binglog_Do_Db for the same db
try to remove Binglog_Do_Db from config file and restart mysql and start replication again
I'm using mysql 5.22 version for master and slave replication. when I execute the show slave status command it's showing slave_io_state as connecting. how to solve this problem.
Please help me the same.
Regards,
Yasar
From here-
run a "show master status" on the master DB. It will give you the
correct values to update your slave with. From your slave status, it
looks like your slave has successfully connected to the master and is
awaiting log events. To me, this means your slave user has been
properly set up, and has the correct access. It really seems like you
just need to sync the correct log file position. Careful, because to
get a good sync, you should probably stop the master, dump the DB,
record the master log file positions, then start the master,import the
DB on the slave, and finally start the slave in slave mode using the
correct master log file pos. I've done this about 30 times, and if you
don't follow those steps almost exactly, you will get a bad sync.
Else go through this(How to set up replication) again, to see if there are some config problem.
If Slave I/O thread is showing Connecting to Master status check these things:
Verify the privileges for the user being used for replication on the
master.
Check that the host name of the master is correct and that you are using the correct port to connect to the master. The port used for replication is the same as used for client network communication (the default is 3306). For the host name, ensure that the name resolves to the correct IP address.
Check that networking has not been disabled on the master or slave. Look for the skip-networking option in the configuration file. If present, comment it out or remove it.
If the master has a firewall or IP filtering configuration, ensure that the network port being used for MySQL is not being filtered.
Check that you can reach the master by using ping or traceroute/tracert to reach the host.
I have been trying to start replication in a mysql database. I followed all the steps from the mysql manual to setup and configure the replication.
http://dev.mysql.com/doc/refman/5.1/en/replication-howto.html
I could start the replication without any trouble. Newly inserted data was replicated properly.
But after a while I observed that though INSERT are working, the UPDATEs are not replicating. So, my replicated database contains data just as it was inserted first time.
My master database is on an UNIX server with MYSQL-5.1.56. The slave is used in Windows using WAMP package with MYSQL 5.5.8. I have also tried a slave with lower version mysql with WAMP5, with same effect.
Please share your ideas and experience on this. Thanks.
I have similar problem. I know it's old thread but it can help others:
link: mysql replication works only if I choose database by USE database
I sorted it out a few months ago. The problem was, I tried to replicate only one single database, and set binlog_do_db and binlog-ignore-db options in master to select only that database. But that left out any statement which was executed without selecting database by USE database, as kayn said. Using replicate-ignore-db and replicate-do-db options in slave would do the same. So I finally fixed it by using the replicate-wild-do-table option in the slave, referenced here. Added the following line in the configuration of the slave server.
replicate-wild-do-table=mydb.%
How do I go about setting up replication on the same mysql server, i.e master and slave both will be the same server?
My requirement is this: I want to replicate few tables on db2 with db1 located on the same server but not all the tables.
I searched the whole the net there are few example like shown here http://www.ruturaj.net/tutorials/mysql/replication/same-server-rewrite-database
but doesn't work for me.
And many examples which explain about the replication setup on two different server
Can anybody please redirect me to the right link, if any available?
Thanks
Not a big deal; just set up two mysql servers on two different port number.
I've used to choose 3306 for master, and 3307 for slave.
Create a new my.cnf for slave server. ( name it my_slave.cnf )
Edit my_slave.cnf : make it using another port, and put slave settings in it.
Duplicate startup script : /etc/init.d/mysqld to /etc/init.d/mysqld_slave
( or add new commands slavestart, slavestop in it. )
And this is my - very - subjective opinion : separate to-be-replicated and not-to-be-replicated on [database] level not on table level. MySQL supports detailed configuration for replication level, but it'll be very complicated and make others confused after months, years later.
I want to create Database replication i try but some problem is there so give me full steps of How To Set Up Database Replication In MySQL
Never done it personally at work but we do use it.
Seems that you want to setup a master/slave setup, the slave beeing the replicated server.
http://dev.mysql.com/doc/refman/5.0/en/replication-howto.html (check the documentation is up to date with your mysql version.)
Here is a step by step instruction how to get MySQL master-slave replication automatically installed and later scaled http://blog.jelastic.com/2017/03/14/scalable-mysql-master-slave-replication/ (if you are ready to run this cluster in the specific cloud)