MySQL slave with LVM

UNFINISHED first few lines...

Create LVM snapshot

Get the data mount

# df -h $(mysql --batch --skip-column-names -e "show variables like 'datadir'" | awk '{print $NF;}')
Filesystem                         Size  Used Avail Use% Mounted on
/dev/mapper/vg--mysql-mysql--data  138G   78G   55G  59% /var/lib/mysql

Enough space for a snapshot?

# vgs vg-mysql
  VG       #PV #LV #SN Attr   VSize   VFree 
  vg-mysql   2   3   1 wz--n- 199,99g 20,00g

Create a concsistent snapshot

master # mysql -e "FLUSH TABLES WITH READ LOCK; SHOW MASTER STATUS;" > /var/lib/mysql/master_status.$(date "+%Y%m%d_%H%M%S")
master # lvcreate -l50%FREE -s -n mysql-data-snap /dev/vg-mysql/mysql-data
master # mysql -e "UNLOCK TABLES;"
master # mount /dev/vg-mysql/mysql-data-snap /mnt

master # cat /mnt/master_status.20151002_225659 
File	Position	Binlog_Do_DB	Binlog_Ignore_DB
mysql-bin.002366	263911913

master # mysql --batch --skip-column-names -e "show variables like 'innodb_data_file_path'"
innodb_data_file_path	ibdata1:5G;ibdata2:5G;ibdata3:5G;ibdata4:50M:autoextend

Set the innodb_data_file_path to the same value on the slave.

Copy the data to the slave

slave# ssh -c blowfish master "cd /mnt ; tar cSpzf - ." | ( cd /var/lib/mysql ; tar xlvSpzf - )