Spider's HA structure includes data nodes, spider nodes, and monitoring nodes. Data nodes store data, spider nodes provide load balancing and failover, and monitoring nodes monitor data nodes. To add a new data node without stopping service: 1) Create a new table on the node, 2) Alter tables on monitoring nodes to include new node, 3) Alter clustered table connection to include new node, 4) Copy data to new node. This maintains redundancy when a node fails without service interruption.

1. HA feature of Spider
Kentoku SHIBA
kentokushiba at gmail dot com

2. Basic structure

3. Basic structure
tbl_a tbl_a tbl_a
DB11 DB12 DB13
Data nodes
tbl_a
DB7 tbl_a
DB7
DB6 DB6
DB1 DB21
Spider nodes Monitoring nodes
Spider's HA structure is composed of
data nodes, spider nodes and monitoring nodes.

4. The part of structure
- Data nodes
Data nodes store real data.
Each data node that linked same Spider table store same data.
(like RAID 1)
- Spider nodes
The entrance of user access.
Spider nodes offer load balance, fail over and transparently access to
data node.
- Monitoring nodes
Monitoring nodes monitor data nodes.

5. Monitoring parameters
- monitoring_bg_interval(mbi)
Interval of background monitoring.(microsecond)
The default value is 10000000
- monitoring_bg_kind(mbk)
The kind of background monitoring.
0 : It doesn't monitor.
1 : It monitors state of connection.
2 : It monitors state of a table without where clause.
The default value is 0

6. Monitoring parameters
- monitoring_kind(mkd)
The kind of monitoring.
0 : It doesn't monitor.
1 : It monitors state of connection.
2 : It monitors state of a table without where clause.
The default value is 0
- monitoring_limit(mlt)
The limititation of records at monitoring table.
(Only when monitoring_kind is bigger than 1, it is effective.)
0 or more : Number of limitation.
The default value is 1
- monitoring_server_id(msi)
The server_id of monitoring MySQL server.
The default value is self server_id

7. How to set up HA
without stopping the service

8. How to set up HA
Spider can set up HA by each table.
Here, I will explain how to set up HA,
without stopping service.

9. Initial Structure
tbl_a Create table tbl_a (
col_a int,
DB2 col_b int,
primary key(col_a)
Create table tbl_a ( ) engine = InnoDB;
col_a int,
col_b int,
primary key(col_a)
) engine = Spider
Connection ‘ tbl_a
table “tbl_a”,
user “user”,
password “pass”,
DB1
host “DB2”
‘;
There are 1 MySQL server with Spider and 1 remote
MySQL server without Spider.

10. Step 1
tbl_a tbl_a tbl_a
DB2 DB3 DB4
tbl_a Create table tbl_a (
col_a int,
DB1 col_b int,
primary key(col_a)
) engine = InnoDB;
Add new data nodes(DB3 and DB4) and tables.

11. Step 2
tbl_a tbl_a tbl_a
DB2 DB3 DB4
Create table tbl_a (
col_a int,
col_b int,
primary key(col_a)
) engine = Spider
tbl_a Connection ‘
table “tbl_a”,
DB1 tbl_a
DB7 user “user”,
password “pass”,
DB6 host “DB2 DB3 DB4”
DB5 ‘;
Add new monitoring nodes
(DB5, DB6, DB7) and tables.

12. Step 3
insert into mysql.spider_link_mon_servers
(db_name, table_name, link_id, sid, server, scheme, host, port, socket, username, password)
values
tbl_a tbl_a tbl_a
('db_name', 'tbl_a', 0, DB5_sid, null, 'mysql', 'DB5', 3306, null, 'user', 'pass‘),
('db_name', 'tbl_a', 0, DB6_sid, null, 'mysql', 'DB6', 3306, null, 'user', 'pass‘),
DB2 DB3 DB4
('db_name', 'tbl_a', 0, DB7_sid, null, 'mysql', 'DB7', 3306, null, 'user', 'pass‘);
Alter table tbl_a
Connection ‘
table “tbl_a”,
user “user”,
password “pass”,
host “DB2 DB3 DB4”, tbl_a
mbk “2”, mkd “2”,
msi “DB5_sid”, DB1 tbl_a
DB7
link_status “0 2 2” DB6
‘; DB5
Register monitornig node information to
MySQL servers with Spider.
Then alter table on DB1.

13. Step 4
tbl_a tbl_a tbl_a
DB2 DB3 DB4
tbl_a Select spider_copy_tables(‘tbl_a’, ‘’, ‘’);
DB1 tbl_a
DB7
DB6
DB5
Copy data from DB2 to DB3 and DB4.

14. Finish
tbl_a tbl_a tbl_a
DB2 DB3 DB4
Alter table tbl_a
Connection ‘
table “tbl_a”,
user “user”,
password “pass”,
host “DB2 DB3 DB4”, tbl_a
mbk “2”, mkd “2”,
msi “DB5_sid”,
link_status “0 1 1”
DB1 tbl_a
DB7
‘;
DB6
DB5
Alter table on DB1.

15. How to add new node
after failover
and preparing new server
without stopping the service

16. Create a table of a new node to the clustered table
You need to create a new node, in order to
maintain redundancy, when there is a trouble
at the node that composes the cluster.
Here, I will explain how to add a table of a
new node, without stopping the service.

17. Initial Structure
tbl_a tbl_a tbl_a
DB2 DB3 DB4
tbl_a
DB1 tbl_a
DB7
DB6
DB5
There are 4 MySQL servers with Spider
(include 3 monitoring nodes) and
3 MySQL servers without Spider (including 1 broken node).

18. Step 1
tbl_a tbl_a tbl_a tbl_a
DB8 DB2 DB3 DB4
Create table tbl_a ( tbl_a
col_a int,
col_b int,
DB1 tbl_a
DB7
primary key(col_a)
DB6
) engine = InnoDB;
DB5
Add new data node(DB8) and table.

19. Step 2
tbl_a tbl_a tbl_a tbl_a
DB8 DB2 DB3 DB4
Alter table tbl_a
tbl_a Connection ‘
table “tbl_a”,
user “user”,
DB1 tbl_a
DB7 password “pass”,
DB6 host “DB2 DB4 DB8”
DB5 ‘;
Alter table on monitoring nodes
(DB5, DB6 and DB7).

20. Step 3
tbl_a tbl_a tbl_a tbl_a
DB8 DB2 DB3 DB4
Alter table tbl_a
Connection ‘
table “tbl_a”,
user “user”,
password “pass”,
host “DB2 DB4 DB8”, tbl_a
mbk “2”, mkd “2”,
msi “DB5_sid”, DB1 tbl_a
DB7
link_status “0 0 2” DB6
‘; DB5
Alter table on DB1.

21. Step 4
tbl_a tbl_a tbl_a tbl_a
DB8 DB2 DB3 DB4
tbl_a Select spider_copy_tables(‘tbl_a’, ‘’, ‘’);
DB1 tbl_a
DB7
DB6
DB5
Copy data from DB2 to DB8.

22. Finish
tbl_a tbl_a tbl_a tbl_a
DB8 DB2 DB3 DB4
Alter table tbl_a
Connection ‘
table “tbl_a”,
user “user”,
password “pass”,
host “DB2 DB4 DB8”, tbl_a
mbk “2”, mkd “2”,
msi “DB5_sid”, DB1 tbl_a
DB7
link_status “0 0 1” DB6
‘; DB5
Alter table on DB1.

23. Any Questions?
Thank you for taking
your time!!
Kentoku SHIBA (kentokushiba at gmail dot com)
http://wild-growth.blogspot.com/
http://spiderformysql.com