MYSQL :: Procedures To Promote Slave To Master Server

MyISAM On Master And InnoDB On Slave Server
Is this possible to have a MyISAM table on master server and change its storage engine (to InnoDB) on slave server in a replication environment?

If this is possible, what should I consider before changing MyISAM to InnoDB on slave server?

Here is the table structure:

Master/Slave Restoration.
I have 2 servers (A and B) setup as Master and Slave respectively.
Upon A's failure, all client's request will be directed to B.

How can I set A to become master again after its been restored from
its failure? In chapter 4.10 of mysql docs, it mentioned (vaguely)
that A will become B's slave to sync all operations that had happened
after the failure. Finally, upon full sync switch A to become Master
again and B to slave.

How can I setup A to be a slave of B? The problem I faced is that I
can't find out what the bin log and position is from B since "show
master status" is always empty. I guess B still thinks its a slave.

MySQL Master/Slave
In the case of 2 3.23.X series mysql databases in a master/slave
replication setup (myiasm tables), if a FLUSH TABLES WITH READ LOCK is
put on the slave, does the master effectively lock too because it is
waiting for the binlog update(s) to be confirmed from the slave, or
does the master merrily carry on not caring in the least that the
slave tables are locked?

Master/slave Setup To Do Replication
using mysql 4.1.7, have a master/slave setup to do replication.

Is there anyway to prevent the slavedb from accepting inserts other than the replication inserts?

If rows do get inserted directly into the slave, there is an error because the two databases no longer match. Is there anyway to recover from this?

Forwarding Insert/Updates From Slave To Master
Is there a way within MySQL to forward all Inserts/Update requests from the
Slave to the Master, or much I rearchitect my application to carry two
connection; one connection to the Master for updates and the other
connection to the slave for Selects?

MySQL Replication (Multiple Master & 1 Slave)
Is it possible to replicate 2 or more master server & 1 slave server?

I have tried 1 master & multiple slave running but I want to try 4 master server & 1 slave server. Is this possible?

Restart Slave After Master Has Died In Replicated Environment
Our master database ran out of connections and we had to restart the
server (couldn't SSH into the box). Rebooting the server worked and
of our clients resumed activity.

The problem is that the slave didn't start automatically so I tried to
do a START SLAVE; on it.

This is the latest shown in the error log on the slave.

040110 20:06:13 Error reading packet from server: binlog truncated in
the middle of event (server_errno=1236)
040110 20:06:13 Got fatal error 1236: 'binlog truncated in the middle
of event' from master when reading data from binary log
040110 20:06:13 Slave I/O thread exiting, read up to log
'user1_master.002', position 802078191

(THIS IS AFTER I DID A SLAVE_START TODAY 1/20)

040120 8:56:39 Slave I/O thread: connected to master
'slave@db1.ezboard.com:5000', replication started in log
'db1_master.002' at position 802078191
040120 8:56:39 Slave: there is an unfinished transaction in the
relay log (could find neither COMMIT nor ROLLBACK in the relay log);
it could be that the master died while writing the transaction to its
binary log. Now the slave is rolling back the transaction. Error_code:
0
040120 8:56:39 Error running query, slave SQL thread aborted. Fix
the problem, and restart the slave SQL thread with "SLAVE START". We
stopped at log 'db1_master.002' position 802078147.

Mysql Master/Slave Read Write To Database Question
If I setup my database as master/slave and user enters data into the html form. This data is written to the master database. After html form submission user is directed to view.html to view the submitted data. The view.html page does the read from the slave. Would it be safe to assume that the data that user submitted would be written to master and immediately displayed in the view.html by reading slave data base?

Replication, Slave Thread: Error Connecting To Master: Access Denied For User:
I have MySQL 3.23.41 on a RH-7.2 Linux used as local server. I'm trying to replicate the databases from server (192.168.0.1) to another linux PC (192.168.0.3).

Following the manual, i grant to the master a user with file privileges, and
edit both my.cnf files. The master starts fine but the slave mysql.log shows up an error:

Slave thread: error connecting to master: Access denied for user:
replica@localhost' (Using password: YES) (0), retry in 60 sec

Muti Master Server Replication
I need some help in setting up multi master server replication
setup fpr my project. Till now I have set up single master replication, but had not been able to manage anythin on mulitimaster setup.

Master Master Replication, Truncate Table Fails, Version 5.0.22
I have set up a master master replication link between two databases, prototyping an idea. Anyhow, adding records and deleting works, both get updated, creating and dropping tables works, but truncating tables doesn't work.

My main questions are, why doesn't truncate work, and if it doesn't work, what else doesn't work across a master-master replication link?

Master/Master Replication Problems
I was wondering whether someone could help me.

I have inherited set of replicated servers from a guy I used to work with, basic set up is:

Master1/Slave2 - Server ID 1
Master2/Slave1 - Server ID 2

When I looked at the logs it looks as though Server ID 2 is well out of step. Having looked at the slave status it appears that that Slave_SQL_Running state is set to No and a particular piece of SQL is causing the problem. Having ran the SQL on the particular server it has now problem at all.

Now my understanding of this type of set up is that Server ID 1 writes directly to Server ID 2, then Server ID 1 is in turn replicated to.

But for the life in me, I cannot understand why this piece of SQL is causing the problem. Can anyone offer me any ideas on how I can best get to the bottom of this, I'm really struggling with this. There was me thinking replication just worked!

Is there an ability to get MySQL to log all queries it is running, so I can get to the bottom of all queries currently being executed?

Master / Master Asynchronous Replication
Currently we have a web based application that is mostly reads (4:1
r/w). It is using a single MySQL database server. Is there any way to
have two database servers in a master/master configuration such that
writes to either database server are replicated to eachother. Basically
even though we have a 4:1 ration of read/write the writes happen often
enought that when the database goes down the app stops working. I know
how to get this working in Oracle (insert big laugh here) but Oracle is
cost prohibitive. Any pointers?

NOW() At Replication Slave
We have 3 MySQL servers in replication, 1 master and 2 slaves. One slave server is 300 seconds behind the master due to heavy SELECT statements.

If I run INSERT query (containing NOW()) on master at 10:00 AM, what time will be saved in the slave server which is 300 seconds behind? The query is

MySQL Code:

INSERT INTO users (username, password, signup_date_time) VALUES ('user1', 'pass1', NOW())

Can't Set-up Slave In Replication
I'm trying to set-up replication following a book and on-line guide. This
is over SSH with a tunnel (not sure if the tunnel's required).

The master appears to be set-up OK (easy enough).
The slave however isn't behaving.

I've got a my.cnf with the following:

[mysqld]
master-host=127.0.0.1
master-port=APORT
master-user=AUSER
master-password=APASSWORD
server-id=2

When I start the slave up and do show slave status - I get 0's and
blank entries back.

I've tried setting it up using:

CHANGE MASTER TO
MASTER_HOST='localhost',
MASTER_USER='AUSER',
MASTER_PORT=APORT,
MASTER_PASSWORD='APASSWORD',
MASTER_LOG_FILE='AFILE-bin.001',
MASTER_CONNECT_RETRY=10;

This sets up the slave bits and show slave status looks much better,
however,

SLAVE START;

returns...

The server is not configured as slave, fix in config file or with CHANGE
MASTER TO

I can only seem to find this message in pages that have a list of all Mysql
errors.

MySQL Slave
We are having problems where at least once a day our MySQL slave server gets about 1700 seconds behind the master.Any ideas what is causing this? I looked in .err logs and it says nothing.A simple stop/start brings it back to to 0.

Slave Servers
i have do replication with 1 master server to 3 slave servers.
And i want to grant the 3 slave servers only select option for all user;

Reconnect Slave
Is it possible to re-connect the slave db to a master after it has been out of sync for 2 days?I can't seem to figure it out and it is a pain to have to redump all the data and re-import all the data as I have over 20 different databases.

Flushing Writes On Slave Db
i need to make a slave database "READ" only.ie, it must not not respond to data manipulation commands. i want only "select * from table_name" command to work on the tables in the replicated db on the slave. How must i go about it?

Replication - START SLAVE
When I try to start the slave for replication

I get a sytax error:

START SLAVE;

not much should be able to go wrong when you're typing in two words.

Replication: 2 Masters And 1 Slave
I need to replicate 2 databases (each one resides in a different
server) to a single slave server. Reading the documentation I have
running the master/slave replication, but i need to replicate the
other database too, the problem is: I need replicate the other
database and that database exists in the other server, so how I
configure the other master server/datatabase in the slave?

Replication Database On Slave Is Not Updated
We are using mysql v4.0.24 on Linux machines.

I'm trying to set up replication with a master and only one slave
database.

The syncronization seems to work well, the relay file on slave is wrote
correctly (Read_Master_Log_Pos and Relay_Log_Pos are updated) but the
information on slave database is not updated.

Master and slave are sincronyzed as shown below but for some reason I
don't understand. I have to say thay sometimes the replication worked but sometimes
setting up a new slave or changing a slave to master it does not. Code:

Masters Replicating To A Single Slave
I have two big databases in two different servers, each database
it's different too and I need to replicate each one to a single
mysql slave server.

I need this:

MasterA ---> SlaveC <-- MasterB

So, I need dbA and dbB replicated on the slave server C.

Slave-load-tmpdir Option
I have just installed mysql server 5.0. However, when I was trying to start the server by invoking mysqld, it complained that a directory/file is not found.

I then viewed the variable names and found that the slave-load-tmpdir variable was pointing to a non-existing path. I have tried

mysqld --slave-load-tmpdir=<my new path> --standalone

but whenever I restart the mysqld, the variable is still defaulted to that old path....what should I do to change the default setting for this variable?

Drive Failed Now Mounted As Slave How To Recover Db's??
I had a server lose a drive. This customer didnt back his database. I
mounted old failing drive as a slave and can see .frm .MYI & .MYD But if I
copy them to /var/lib/mysql/db_name it says .frm doesnt exist ???? How do I
fix this????

Command SHOW SLAVE STATUS G, Shows That SLAVE_IO_RUNNING
I am trying to set up a master/slave replication.. I followed the instructions in the mysql manual.. I am using mysql 4.0.12 installed in windows xp... I have found out that the replication is not working ...

when i make the command SHOW SLAVE STATUS G, it shows that SLAVE_IO_RUNNING : No.
How can I make this run? What could have I done wrong?

Relay-bin On Master?
I am getting relay-bin logs on my master server. They are all empty except
for one line that reads:

þbin

I have no slave settings in my my.cnf file. Any idea where these are coming
from and how to turn them off?

Replication From 2 Master
I am running MySQL V4.0.14 with replication. I want to replicate specified databases from 2 different masters into one slave. Is this possible?

Relay-bin On Master?
I am getting relay-bin logs on my master server. They are all empty except
for one line that reads: þbin

I have no slave settings in my my.cnf file. Any idea where these are coming
from and how to turn them off?

Replication From 2 Master
I am running MySQL V4.0.14 with replication.

I want to replicate specified databases from 2 different masters into one
slave. Is this possible?

Clustering And Master Down
I want to create replication databases with multiple servers, but i need more informations about consequences when the MASTER database crash : what happens ?

And, if one slave crash : what happens ?

Is it like RAID 5, mysql just work in degraded mode and continue to work, or is it fatal ?

Can we compare the replication system by MySQL with the Grid Computing of Oracle ?
I don't think MySQL offers a clustering mode for calculating and searching rows, am i wrong ?

Two Master Servers
I am using two master servers that are synchronized with each other so that if one of them gets disconnected, the other one could take over and no data is lost.
Now my problem is doing backup on the servers. Say I am doing backup on Master 1 and after backup, I will delete the data. So, since Master 2 is synchronized with Master 1, will the deleted data be written back to Master 1?
My batch file is something like this.
echo Executing MYSQL BACKUP
mysqldump -uroot -proot --result-file=%SAVPATH%%FILENAME%".sql" database1
echo Executing MYSQL DELETE
mysql -uroot -proot datalog < "C:Program FilesMySQLMySQL Server 5.0inscript.sql"
Script.sql will call the command "DELETE from table1" for me.

Dual Master Follow-up
I posted a much longer winded question in the replication forum a few days ago, but after much research I realized I just need one piece of information that I seem to be reading conflicting opinions regarding. Is a dual master configuration considered bad form for MySQL Network users? I'm only replicating ONE dynamic database, and there are NO auto-increment fields.

I will have a max of 40 concurrent users (20 average), so I don't think I'll have a big problem with anything becoming out of sync. Should I avoid writing on both machines or is the autoincrement issue the only reason why writing to both masters would cause a problem?

Master Servers Merge
I want to make query to merge table1 from master server A and table2 from master server B (ex: select * from table1, table2) because my site becomes heavy traffic and database gets bigger. It means I need to separate tables and create new database on other master server B. Do you know how to make "merge" from master server A and B?

Master-connect-retry
I installed MySQL 4.0.14 on a new Linux machine unde the form of two
servers: one master and one slave.

I met many unsynchronized events so it was appears conflicts from this late
of the changes from master to slave. I put the master-connect-retry to 2.
Now it seems to work clearly but I cannot see the master-connect-retry
variable with "show variables" command. Is this bad? Shall I have another
unsynchronized events in the future between master and slave?

I manually repaired each conflict or I did RESET MASTER/SLAVE to escape from
the errors' labirint.

Mast-Master Replication
I am unable to find any information about master-master replication. I
need to replicate 1 mysql server over to other as a standby master
server.

Mast-Master Replication
I am unable to find any information about master-master replication. I need to replicate 1 mysql server over to other as a standby master server.

Dual-master Replication
I would like to set up a dual-master replication setup for my MySQL
database
(running on RedHat 9). Could someone please point me to appropriate
website that details this setup process and management as well (i.e.
what should I do if one of the masters goes down?).

Also, are there any solutions that allow auto-increment fields in this
kind of setup?

Mast-Master Replication
I am unable to find any information about master-master replication. I
need to replicate 1 mysql server over to other as a standby master
server.

Show Master Logs
When would SHOW MASTER LOGS be used?
I've had mysql hang 4 times this week and we've done all we can to fix it - but it seems that what we have done has only reduced the backlog of queries that occur when it hangs - now it hung again this morning and the only thing of note in the mysqladmin process list was SHOW MASTER LOGS - I googled it and there seemed to be a few cases of crash related bugs with this particular command - now I know I didnt issue the command so what would have done

Replication With Master And Several Slaves/Masters
At the company I'm working (a road survey centre) where about to start a new project.

We're planning to create web-based application with php, javascript, maybe we're going to use AJAX but certainly combined with a MySQL database to store all of the data.

Since users/researchers have to be able to work off-line on a laptop. Our idea was to install, via XAMPP or something like that, the complete package (i.e. Apache, PHP, MySQL) on each laptop. On a main server we have the same but probably a Linux system.

Now, I know it is possible to replicate the DB on the laptops with the main DB. But is it also possible to update/replicate the main DB with results from the/a laptop after working a day off-line? So it becomes available on each laptop after they done a replication from the main DB?

Maybe a long post for a small question, but I wanted to draw the "context" in wich it is going to be used. A question you are about going to ask me probably is: "why they have to be able to work off-line?" Quite simple: Not everywhere in the world you have wireless internet access + the onsite laptops need to communicate on site with serial devices GPS, Gyroscope, and such like. Wich is for a webbased application running on a server thousand miles rather difficult...

Linking Master Db With Other 3rd Party Plugin Dbs
I imagine this is a somewhat n00bish question, bear with my while I learn the ins and outs :)

I'm constructing a master product DB (MySQL) and have some other 3rd party (PHP) contributions I'd like to use in the interest of not re-inventing the programming wheel.

Specifically PHP Point of Sale, and osCommerce down the road. How can I link certain columns together so I don't have to re-enter information. For example, if I have my own master product table, with a column called 'description.' how can I link that with PHP Point of Sale's 'description' column?

Cannot Create Mysql-test/var/run/master.pid
ERROR: /tmp/edearl/mysql-4.0.21/mysql-test/var/run/master.pid was not
created in 30 seconds; Aborting

This error occurred just after MySQL was installed by root on Linux
2.4.22 (Fedora).

PROBLEM WITH PURGE MASTER LOGS
I have a Server Linux with mysql 4.0.13 version with qmail server.

I run the command purge master logs but he return a message of error i/o.
The table "relay" on db vpopmail is corrupt and the command repair or restore not function.

Dual Master Replication In MySQL 4.1
I have been charged with the task of setting up dual master replication with our company's MySQL servers. I know that their are inherent auto_increment problems with this set up, and the mechanisms to fix this problem weren't introduced until version 5.0.

Can anyone give me some tips, pointers, or advice for safely setting up this replication topology in 4.1? Are there any steps I can take to make sure there are no auto_increment issues? Has anyone had experience setting this up?

Replication Master Crashed After 6 Hours
I recently setup replication, the master and slaves appears to work
fine initially. After about 6 hours, the master mysqld process will
start to consume 99% CPU and the load (avg. load per minute) will go
to 3, 4, 6, 15, 24, 56, 312... in a matter of seconds! The master then
stops responding and needs a reboot. This problem is reproducible, I
have tested a few times.

This is a screenshot of "top" command just before the master died:
http://choonkeng.hopto.org/temp/replication-hang.gif

There are plenty of memory and no disk swapping when the master goes
99%. Error and slow logs don't show any useful information.