Problem with MySQL Master/Slave reboot when in replication

Question

There is a master and number of slaves connected to it.

Due to some patches, we have to Reboot the Master and Slave.

Afterwards, we have to make sure replication is running fine.

While doing this process, what precautions should I take so that I don't get stuck anywhere? After rebooting, I also have to validate that all the slaves are working fine.

Answer 1

• Step 01) STOP SLAVE; on all Slaves

• Step 02) service mysql stop on the Master

• Step 03) Reboot Master

• Step 04) For each Slave

  • Reboot each Slave
  • If /etc/my.cnf has skip-slave-start, then run START SLAVE;

• Step 05) Check that each Slave is fully running

Run the following on the command line

SLAVETHREADCOUNT=`mysql -u... -p... -AN -e"SHOW PROCESSLIST" | grep -c "system user"`
echo ${SLAVETHREADCOUNT}

If SLAVETHREADCOUNT is 2, replication is fully operational.

Give it a Try !!!