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MySQL MHA
2022-06-21 06:58:00 【Lost】
One 、 What is? MHA
1、MHA The concept of
- MHA（MasterHigh Availability） It's an excellent set of MySQL Software for failover and master-slave replication in high availability environment .
- MHA The emergence of is to solve MySQL Single point problem .
- MySQL During failover ,MHA Can do 0-30 Seconds Automate failover operations .
- MHA In the process of failover Ensure the consistency of data to the greatest extent , To achieve real high availability .
2、MHA The composition of
- MHA Node（ Data nodes ）
- MHA Node Running on the Each station MySQL Server .
- MHA Manager（ The management node ）
- MHA Manager It can be deployed separately on a separate machine , Manage multiple master-slave colony ; It can also be deployed in one slave Node .
- MHA Manager Meeting Regularly detect... In the cluster master node . When master Failure time , It can automatically send the latest data to slave Upgrade to a new master, And then put all the other slave Point back to the new master. The entire failover process is completely transparent to the application .
3、MHA Characteristics
- During automatic failover ,MHA Trying to save binary logs from the down primary server , Ensure that data is not lost to the greatest extent
- Use semi synchronous replication , Can greatly reduce the risk of data loss , If only one slave Has received the latest binary log ,MHA You can apply the latest binary logs to all other slave Server , Therefore, the data consistency of all nodes can be guaranteed
- at present MHA Support one master multi-slave architecture , At least three servers , That is, one master and two slaves
4、MySQL Database cluster architecture , How to ensure high availability
- One master two / Three from , For high availability solutions MHA,MMM.
- MHA The architecture will be in all MySQL Server installation mha node Components , It will also be on a separate server / Some one slave Install on node mha manager Components .
- manger The component will detect the in the cluster regularly master Is the node alive , If master fault ,manger It will automatically upgrade one with the latest data slave Become a new in the cluster master, And then the other slave The node points back to the new Master, Complete the new master-slave synchronization , So as to achieve MySQL In the cluster master High availability and data consistency .
Two 、 build MySQL+MHA
1、 Get ready
- MHAmanager：192.168.132.50 MHA node Components 、manager Components
- Slave1：192.168.132.51 mysql-boost-5.7.20.tar.gz、MHA node Components
- Slave2：192.168.132.52 mysql-boost-5.7.20.tar.gz、MHA node Components
- Master：192.168.132.53 mysql-boost-5.7.20.tar.gz、MHA node Components
Turn off firewalls and security
systemctl
stop
firewalld
systemctl
disable
firewalld
setenforce
0
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2、 modify mysql The hostname of the node
hostnamectl
set
-
hostname
mysql1
su
-
hostnamectl
set
-
hostname
mysql2
su
-
hostnamectl
set
-
hostname
mysql3
su
-
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3、 Modify three MySQL The main profile of the server /etc/my.cnf, And create a command soft link
mysql1：192.168.132.51
vim
/
etc
/
my.
cnf
[
mysqld]
server
-
id
=
1
log_bin
=
master
-
bin
log
-
slave
-
updates
=
true
systemctl
restart
mysqld
ln
-
s
/
usr
/
local
/
mysql
/
bin
/
mysql
/
usr
/
sbin
/
ln
-
s
/
usr
/
local
/
mysql
/
bin
/
mysqlbinlog
/
usr
/
sbin
/
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mysql2：192.168.132.52
mysql3：192.168.132.53
vim
/
etc
/
my.
cnf
server
-
id
=
2
#server
-
id
=
3
mysq3 Then for 3, Three servers
server
-
id
It can't be the same
log_bin
=
master
-
bin
relay
-
log
=
relay
-
log
-
bin
relay
-
log
-
index
=
slave
-
relay
-
bin.
index
systemctl
restart
mysqld
ln
-
s
/
usr
/
local
/
mysql
/
bin
/
mysql
/
usr
/
sbin
/
ln
-
s
/
usr
/
local
/
mysql
/
bin
/
mysqlbinlog
/
usr
/
sbin
/
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4、 To configure MySQL One master and two slaves
mysql1：192.168.132.51
mysql2：192.168.132.52
mysql3：192.168.132.53
1. all MySQL Server run MySQL to grant authorization
mysql
-
uroot
-
p123456
grant
replication
slave
on
*.
*
to
'myslave'
'192.168.132.%'
identified
by
'123456';
grant
all
privileges
on
*.
*
to
'mha'
'192.168.132.%'
identified
by
'manager';
grant
all
privileges
on
*.
*
to
'mha'
'mysql1'
identified
by
'manager';
grant
all
privileges
on
*.
*
to
'mha'
'mysql2'
identified
by
'manager';
grant
all
privileges
on
*.
*
to
'mha'
'mysql3'
identified
by
'manager';
flush
privileges;
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2. stay Master Node to view binaries and synchronization points
mysql1：192.168.132.51
show
master
status;
# Everyone's binary file name or offset may be different , Remember your
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3. stay Slave1、Slave2 The node performs a synchronization operation
mysql2：192.168.132.52
mysql3：192.168.132.53
change
master
to
master_host
=
'192.168.132.51',
master_user
=
'myslave',
master_password
=
'123456',
master_log_file
=
'master-bin.000001',
master_log_pos
=
1747;
start
slave;
show
slave
status
\G
Slave_IO_Running:
Yes
Slave_SQL_Running:
Yes
# commonly
Slave_IO_Running:
No
The possibility of ：
# The Internet is not working
#my.
cnf Configuration problem
# password 、file file name 、pos The offset is not right
# The firewall is not closed
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4.Slave1、Slave2 The node is set to read-only mode
mysql2：192.168.132.52
mysql3：192.168.132.53
set
global
read_only
=
1;
# Change back to read-write state set
global
read_only
=
0;
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5. Master slave replication verification
mysql1：192.168.132.51
create
database
test;
use
test;
create
table
test(
id
int);
insert
into
test
values(
1);
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mysql2：192.168.132.52
mysql3：192.168.132.53
5、 install MHA Software
1. All servers have MHA Dependent environment
MHAmanager：192.168.132.50
mysql1：192.168.132.51
mysql2：192.168.132.52
mysql3：192.168.132.53
- First installation epel Source , need Online source installation
- Then install... On all servers node Components
# Install online source
mv
/
etc
/
yum.
repos.
d
/
bak
/
CentOS
-*
/
etc
/
yum.
repos.
d
/
yum
list
yum
install
epel
-
release
--
nogpgcheck
-
y
yum
install
-
y
perl
-
DBD
-
MySQL
\
perl
-
Config
-
Tiny
\
perl
-
Log
-
Dispatch
\
perl
-
Parallel
-
ForkManager
\
perl
-
ExtUtils
-
CBuilder
\
perl
-
ExtUtils
-
MakeMaker
\
perl
-
CPAN
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2. install MHA node software package
- For each operating system, the version is different , here CentOS7.4 Must choose 0.57 edition .
- Must be on all servers Install first node Components , Last in MHA-manager Install on node manager Components , because manager rely on node Components .
# Put the package mha4mysql
-
node
-
0.57.
tar.
gz Put in
/
opt Under the table of contents
cd
/
opt
tar
zxvf
mha4mysql
-
node
-
0.57.
tar.
gz
cd
mha4mysql
-
node
-
0.57
perl
Makefile.
PL
make
&&
make
install
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3. stay MHA manager Install on node manager Components
MHAmanager：192.168.132.50
# Put the package mha4mysql
-
manager
-
0.57.
tar.
gz Put in
/
opt Under the table of contents
cd
/
opt
tar
zxvf
mha4mysql
-
manager
-
0.57.
tar.
gz
cd
mha4mysql
-
manager
-
0.57
perl
Makefile.
PL
make
&&
make
install
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manager After the components are installed, install them in /usr/local/bin The following tools will be generated
- masterha_check_ssh Check MHA Of SSH Configuration status
- masterha_check_repl Check MySQL Copy status
- masterha_manger start-up manager Script for
- masterha_check_status Detect current MHA Running state
- masterha_master_monitor testing master Is it down?
- masterha_master_switch Control failover （ Automatic or manual ）
- masterha_conf_host Add or remove configured server Information
- masterha_stop close manager
node Components will also be installed in /usr/local/bin Several scripts will be generated below （ These tools are usually made of MHAManager The script triggers , There is no need for human operation ）
- save_binary_logs Save and copy master Binary log
- apply_diff_relay_logs Identify differentiated relay log events and apply their differentiated events to other slave
- filter_mysqlbinlog Remove unnecessary ROLLBACK event （MHA This tool is no longer used ）
- purge_relay_logs Clear relay logs （ It won't block SQL Threads ）
6、 Configure password less authentication on all servers
1. stay manager Configure password less authentication to all database nodes on the node
MHAmanager：192.168.132.50
ssh
-
keygen
-
t
rsa
# Press enter all the way
ssh
-
copy
-
id
192.168
.132
.51
ssh
-
copy
-
id
192.168
.132
.52
ssh
-
copy
-
id
192.168
.132
.53
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2. stay mysql1 Configuration to the database node mysql2 and mysql3 No password authentication ssh-keygen -t rsa
mysql1：192.168.132.51
ssh
-
keygen
-
t
rsa
ssh
-
copy
-
id
192.168
.132
.52
ssh
-
copy
-
id
192.168
.132
.53
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3. stay mysql2 Configuration to the database node mysql1 and mysql3 No password authentication
mysql2：192.168.132.52
ssh
-
keygen
-
t
rsa
ssh
-
copy
-
id
192.168
.132
.51
ssh
-
copy
-
id
192.168
.132
.53
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4. stay mysql3 Configuration to the database node mysql1 and mysql2 No password authentication
mysql3：192.168.132.53
ssh
-
keygen
-
t
rsa
ssh
-
copy
-
id
192.168
.132
.51
ssh
-
copy
-
id
192.168
.132
.52
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7、 stay manager Configuration on node MHA
MHAmanager：192.168.132.50
1. stay manager Copy related scripts on node to /usr/local/bin Catalog
cp
-
rp
/
opt
/
mha4mysql
-
manager
-
0.57
/
samples
/
scripts
/
usr
/
local
/
bin
# After copying, there will be four execution files
ll
/
usr
/
local
/
bin
/
scripts
/
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- master_ip_failover When switching automatically VIP Managed scripts
- master_ip_online_change When switching online vip Management of
- power_manager Script to shut down the host after the failure
- send_report Because the script that sends the alarm after the failover
2. When copying the above automatic switching VIP Manage scripts to /usr/local/bin Catalog , Use here master_ip_failover Scripts to manage VIP And failover
cp
/
usr
/
local
/
bin
/
scripts
/
master_ip_failover
/
usr
/
local
/
bin
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# Empty the original content first
echo
''
>
/
usr
/
local
/
bin
/
master_ip_failover
# Directly copy and modify vip Related parameters
vim
/
usr
/
local
/
bin
/
master_ip_failover
#
!/
usr
/
bin
/
env
perl
use
strict;
use
warnings
FATAL
=>
'all';
use
Getopt::
Long;
my (
$command,
$ssh_user,
$orig_master_host,
$orig_master_ip,
$orig_master_port,
$new_master_host,
$new_master_ip,
$new_master_port
);
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
# Add content section
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
my
$vip
=
'192.168.132.200';
# Appoint vip The address of
my
$brdc
=
'192.168.132.255';
# Appoint vip The address of
my
$ifdev
=
'ens33';
# Appoint vip Bound network card
my
$key
=
'1';
# Appoint vip Serial number of the bound virtual network card
my
$ssh_start_vip
=
"/sbin/ifconfig ens33:$key $vip";
# Represents that the value of this variable is ifconfig
ens33:
1
192.168
.132
.200
my
$ssh_stop_vip
=
"/sbin/ifconfig ens33:$key down";
# Represents that the value of this variable is ifconfig
ens33:
1
down
my
$exit_code
=
0;
# Specify the exit status code as 0
#my
$ssh_start_vip
=
"/usr/sbin/ip addr add $vip/24 brd $brdc dev $ifdev label $ifdev:$key;/usr/sbin/arping -q -A -c 1 -I $ifdev $vip;iptables -F;";
#my
$ssh_stop_vip
=
"/usr/sbin/ip addr del $vip/24 dev $ifdev label $ifdev:$key";
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
#
GetOptions(
'command=s'
=>
\$command,
'ssh_user=s'
=>
\$ssh_user,
'orig_master_host=s'
=>
\$orig_master_host,
'orig_master_ip=s'
=>
\$orig_master_ip,
'orig_master_port=i'
=>
\$orig_master_port,
'new_master_host=s'
=>
\$new_master_host,
'new_master_ip=s'
=>
\$new_master_ip,
'new_master_port=i'
=>
\$new_master_port,
);
exit
&
main();
sub
main {
print
"\n\nIN SCRIPT TEST====$ssh_stop_vip==$ssh_start_vip===\n\n";
if (
$command
eq
"stop"
||
$command
eq
"stopssh" ) {
my
$exit_code
=
1;
eval {
print
"Disabling the VIP on old master: $orig_master_host \n";
&
stop_vip();
$exit_code
=
0;
};
if (
$
) {
warn
"Got Error: [email protected]\n";
exit
$exit_code;
}
exit
$exit_code;
}
elsif (
$command
eq
"start" ) {
my
$exit_code
=
10;
eval {
print
"Enabling the VIP - $vip on the new master - $new_master_host \n";
&
start_vip();
$exit_code
=
0;
};
if (
$
) {
warn
$
;
exit
$exit_code;
}
exit
$exit_code;
}
elsif (
$command
eq
"status" ) {
print
"Checking the Status of the script.. OK \n";
exit
0;
}
else {
&
usage();
exit
1;
}
}
sub
start_vip() {
`ssh
$ssh_user
\
\
" $ssh_start_vip \"`;
}
#
#
A
simple
system
call
that
disable
the
VIP
on
the
old_master
sub
stop_vip() {
`ssh
$ssh_user
\
\
" $ssh_stop_vip \"`;
}
sub
usage {
print
"Usage: master_ip_failover --command=start|stop|stopssh|status --orig_master_host=host --orig_master_ip=ip --orig_master_port=port --new_master_host=host --new_master_ip=ip --new_master_port=port\n";
}
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3. establish MHA Software directory and copy configuration files , Use here app1.cnf Configuration files to manage mysql Node server
mkdir
/
etc
/
masterha
cp
/
opt
/
mha4mysql
-
manager
-
0.57
/
samples
/
conf
/
app1.
cnf
/
etc
/
masterha
vim
/
etc
/
masterha
/
app1.
cnf
[
server
default]
manager_log
=/
var
/
log
/
masterha
/
app1
/
manager.
log
manager_workdir
=/
var
/
log
/
masterha
/
app1
master_binlog_dir
=/
usr
/
local
/
mysql
/
data
master_ip_failover_script
=/
usr
/
local
/
bin
/
master_ip_failover
master_ip_online_change_script
=/
usr
/
local
/
bin
/
master_ip_online_change
user
=
mha
password
=
manager
ping_interval
=
1
remote_workdir
=/
tmp
repl_user
=
myslave
repl_password
=
123456
secondary_check_script
=/
usr
/
local
/
bin
/
masterha_secondary_check
-
s
192.168
.132
.52
-
s
192.168
.132
.53
shutdown_script
=
""
ssh_user
=
root
[
server1]
hostname
=
192.168
.132
.51
port
=
3306
[
server2]
candidate_master
=
1
check_repl_delay
=
0
hostname
=
192.168
.132
.52
port
=
3306
[
server3]
hostname
=
192.168
.132
.53
port
=
3306
#
--------------------------
Profile explanation
--------------------------------------------------------------------------
[
server
default]
manager_log
=/
var
/
log
/
masterha
/
app1
/
manager.
log
#manager journal
manager_workdir
=/
var
/
log
/
masterha
/
app1.
log
#manager working directory
master_binlog_dir
=/
usr
/
local
/
mysql
/
data
/
#master preservation binlog The location of , The path here has to do with master Internally configured binlog The path is the same , In order to MHA Can find
master_ip_failover_script
=/
usr
/
local
/
bin
/
master_ip_failover
# Set auto failover When the switch script , That's the script above
master_ip_online_change_script
=/
usr
/
local
/
bin
/
master_ip_online_change
# Set the switch script for manual switching
user
=
mha
# Set up monitoring users root
password
=
manager
# Set up mysql in root User's password , This password is the one that created the monitoring user in the previous article
ping_interval
=
1
# Set up the main monitoring library , send out ping Time interval between packages 1 second , The default is 3 second , Try three times when there is no response failover
remote_workdir
=/
tmp
# Set the remote end mysql When a switch occurs binlog Where to save
repl_user
=
myslave
# Set the user of the copy user
repl_password
=
123456
# Set the password of the copy user
report_script
=/
usr
/
local
/
send_report
# Set the script of the alarm sent after switching
secondary_check_script
=/
usr
/
local
/
bin
/
masterha_secondary_check
-
s
192.168
.132
.52
-
s
192.168
.132
.53
# Specify the slave server to check IP Address
shutdown_script
=
""
# Set to close the failed host script after the failure occurs （ The main function of the script is to shut down the host and prevent brain crack ,
It's not used here ）
ssh_user
=
root
# Set up ssh Login user name of
[
server1]
hostname
=
192.168
.132
.51
port
=
3306
[
server2]
hostname
=
192.168
.132
.52
port
=
3306
candidate_master
=
1
# Set as candidate master, After setting this parameter , After the master-slave switch, the slave database will be promoted to the master database , Even if the main library is not the latest in the cluster slave
check_repl_delay
=
0
# By default, if one slave backward master
exceed 100M Of relay
logs Words ,MHA Will not choose the slave As a new master,
Because for this slave It takes a long time to recover ; By setting check_repl_delay
=
0
,MHA Trigger switch in selecting a new master The replication delay will be ignored , This parameter is set for candidate_master
=
1
Is very useful , Because the candidate must be new in the process of switching master
[
server3]
hostname
=
192.168
.132
.53
port
=
3306
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- 65.
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- 67.
8、 The first configuration needs to be in Master Manually turn on the virtual server on the node IP
mysql1：192.168.132.51
/
sbin
/
ifconfig
ens33:
1
192.168
.132
.200
/
24
- 1.
9、 stay manager Testing on nodes ssh No password authentication
MHAmanager：192.168.132.50
masterha_check_ssh
-
conf
=/
etc
/
masterha
/
app1.
cnf
# If it's normal, it will output
successfully;
# If it fails, you can go to the place where the server has no password authentication to see if there is a problem
- 1.
- 2.
- 3.
10、 stay manager Testing on nodes mysql Master-slave connection
MHAmanager：192.168.132.50
masterha_check_repl
-
conf
=/
etc
/
masterha
/
app1.
cnf
# Last appearance
MySQL
Replication
Health
is
OK
The words indicate normal ;
# appear MySQL
Replication
Health
is
NOT
OK
!
Of , You can have a look mysql Whether there are fewer soft links on the server
-->
Article location ：2、 Modify three MySQL The main profile of the server
/
etc
/
my.
cnf, And create a command soft link
- 1.
- 2.
- 3.
11、 stay manager Start on the node MHA
MHAmanager：192.168.132.50
nohup
masterha_manager
--
conf
=/
etc
/
masterha
/
app1.
cnf
--
remove_dead_master_conf
--
ignore_last_failover
<
/
dev
/
null
>
/
var
/
log
/
masterha
/
app1
/
manager.
log
2
>&
1
&
#
------------------------
Component interpretation
----------------------------------------------------------------------------------
--
remove_dead_master_conf： This parameter represents when a master-slave switch occurs , Old master library
ip
Will be removed from the configuration file .
--
manger_log： Log storage location .
--
ignore_last_failover： By default , If
MHA
Continuous downtime detected , And the interval between two downtime is not enough
8
In an hour , It won't go on
Failover,
The reason for this restriction is to avoid
ping
-
pong
effect . This parameter means to ignore the last
MHA
Trigger the file generated by switching , By default ,MHA
After switching, the directory will be recorded in the log , That is, the log set above app1.
failover.
complete file , The next time you switch again, if you find the file in the directory, you will not be allowed to trigger the switch , Unless you receive a delete file after the first switch , For convenience , I'm going to set it to
--
ignore_last_failover.
- 1.
- 2.
- 3.
- 4.
- 5.
- 6.
- 7.
12、 Check the status
MHAmanager：192.168.132.50
1. see MHA state , You can see the current master yes Mysql1 node .
masterha_check_status
--
conf
=/
etc
/
masterha
/
app1.
cnf
- 1.
2. see MHA journal , Also to see the current master yes 192.168.163.11
cat
/
var
/
log
/
masterha
/
app1
/
manager.
log
|
grep
"current master"
- 1.
3. see Mysql1 Of VIP Address , see Mysql1 Of VIP Address 192.168.163.200 Whether there is , This VIP The address is not because manager Nodes stop MHA Service and disappear .
mysql1：192.168.132.51
ifconfig
- 1.
Add ： To shut down manager service , You can use the following command .
masterha_stop
--
conf
=/
etc
/
masterha
/
app1.
cnf
Or you can directly use
kill
process
ID
The way to turn off .
- 1.
- 2.
3、 ... and 、 fault simulation
1、 fault simulation
1. stay manager Monitoring observation logging on the node
MHAmanager：192.168.132.50
tail
-
f
/
var
/
log
/
masterha
/
app1
/
manager.
log
- 1.
2. stay Master node Mysql1 Stop on mysql service
mysql1：192.168.132.51
systemctl
stop
mysqld
or
pkill
-
9
mysql
- 1.
- 2.
- 3.
After normal automatic switching once ,MHA The process will exit .HMA Will automatically modify app1.cnf The contents of the document , Will be down mysql1 The node to delete .
3. see mysql2 Take over VIP
mysql2：192.168.132.52
ifconfig
- 1.
4. go back to manager Monitoring observation logging on the node
MHAmanager：192.168.132.50
Algorithm of failover alternative master database ：
1
、 In general, the judgment from the database is from （position
/
GTID） Judge the pros and cons , The data are different , Closest to master Of slave, Become a candidate .
2
、 When the data is consistent , In the order of configuration files , Select an alternate master library .
3
、 Set weights （candidate_master
=
1
）, Mandatory assignment of alternate masters by weight .
（1） By default, if one slave backward master
100
M Of relay
logs Words , Even with weight , It's going to fail .
（2） If check_repl_delay
=
0
Words , Even behind a lot of logs , It is also mandatory to choose it as the alternative host .
- 1.
- 2.
- 3.
- 4.
- 5.
- 6.
2、 Troubleshooting steps
1. Repair mysql
mysql1：192.168.132.51
systemctl
restart
mysqld
netstat
-
natp
|
grep
3306
- 1.
- 2.
2. Fix the master-slave
1） In the current main database server Mysql2 View binaries and synchronization points
mysql2：192.168.132.52
mysql
-
uroot
-
p123456
-
e
'show master status;'
# Execute... In the database show
master
status;
- 1.
- 2.
```
2） In the original master database server mysql1 Perform synchronous operation
mysql1：192.168.132.51
change
master
to
master_host
=
'192.168.132.52',
master_user
=
'myslave',
master_password
=
'123456',
master_log_file
=
'master-bin.000001',
master_log_pos
=
1899;
start
slave;
show
slave
status
\G
- 1.
- 2.
- 3.
- 4.
3. stay manager Modify the configuration file on the node app1.cnf
MHAmanager：192.168.132.50
Add this record to it , Because it will automatically disappear when it fails to detect
vim
/
etc
/
masterha
/
app1.
cnf
……
secondary_check_script
=/
usr
/
local
/
bin
/
masterha_secondary_check
-
s
192.168
.132
.51
-
s
192.168
.132
.53
......
[
server1]
hostname
=
192.168
.132
.52
port
=
3306
[
server2]
candidate_master
=
1
check_repl_delay
=
0
hostname
=
192.168
.132
.51
port
=
3306
[
server3]
hostname
=
192.168
.132
.53
port
=
3306
- 1.
- 2.
- 3.
- 4.
- 5.
- 6.
- 7.
- 8.
- 9.
- 10.
- 11.
- 12.
- 13.
- 14.
- 15.
- 16.
- 17.
4. stay manager Start on the node MHA
masterha_stop
--
conf
=/
etc
/
masterha
/
app1.
cnf
nohup
masterha_manager
--
conf
=/
etc
/
masterha
/
app1.
cnf
--
remove_dead_master_conf
--
ignore_last_failover
<
/
dev
/
null
>
/
var
/
log
/
masterha
/
app1
/
manager.
log
2
>&
1
&
masterha_check_status
--
conf
=/
etc
/
masterha
/
app1.
cnf
- 1.
- 2.
- 3.
- 4.
- 5.
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