Note

This document guides how to use 'flashbase' script for scale-out. If you use LTCLI, you can operate Lightning DB more easily and powerfully. Therefore, if possible, we recommend LTCLI rather than 'flashbase' script.

1. Check the distribution of slots¶

You can use 'redis-trib.rb check {master's IP}:{master's Port} | grep slots | grep master' command to check slots assigned to each master. Any master can be used for '{master's IP}:{master's Port}'.

$ redis-trib.rb check 192.168.111.201:18800 | grep slots | grep master

   slots:0-818 (819 slots) master

   slots:3277-4095 (819 slots) master

   slots:5734-6553 (820 slots) master

   slots:7373-8191 (819 slots) master

   slots:13926-14745 (820 slots) master

   slots:4096-4914 (819 slots) master

   slots:8192-9010 (819 slots) master

   slots:2458-3276 (819 slots) master

   slots:9011-9829 (819 slots) master

   slots:10650-11468 (819 slots) master

   slots:11469-12287 (819 slots) master

   slots:1638-2457 (820 slots) master

   slots:12288-13106 (819 slots) master

   slots:15565-16383 (819 slots) master

   slots:9830-10649 (820 slots) master

   slots:819-1637 (819 slots) master

   slots:6554-7372 (819 slots) master

   slots:4915-5733 (819 slots) master

   slots:13107-13925 (819 slots) master

   slots:14746-15564 (819 slots) master

2. Check the distribution of redis-servers¶

$ flashbase check-distribution

check distribution of masters/slaves...

SERVER NAME     | M | S

--------------------------------

192.168.111.201 | 10 | 10

192.168.111.202 | 10 | 10

--------------------------------

Total nodes     | 20 | 20

3. Scale out¶

Open 'redis.properties' with 'flashbase edit' command.

$ flashbase edit

Add a new node("192.168.111.203").

As-is

#!/bin/bash

## Master hosts and ports
export SR2_REDIS_MASTER_HOSTS=( "192.168.111.201" "192.168.111.202" )
export SR2_REDIS_MASTER_PORTS=( $(seq 18800 18809) )

## Slave hosts and ports (optional)
export SR2_REDIS_SLAVE_HOSTS=( "192.168.111.201" "192.168.111.202" )
export SR2_REDIS_SLAVE_PORTS=( $(seq 18850 18859) )

To-be

#!/bin/bash

## Master hosts and ports

export SR2_REDIS_MASTER_HOSTS=( "192.168.111.201" "192.168.111.202" "192.168.111.203" )
export SR2_REDIS_MASTER_PORTS=( $(seq 18800 18809) )

## Slave hosts and ports (optional)
export SR2_REDIS_SLAVE_HOSTS=( "192.168.111.201" "192.168.111.202" "192.168.111.203" )
export SR2_REDIS_SLAVE_PORTS=( $(seq 18850 18859) )

Scale out the cluster with a 'flashbase scale-out {new node's IP}' command. If you add more than one node, you can use like 'flashbase scale-out 192.168.111.203 192.168.111.204 192.168.111.205'.

$ flashbase scale-out 192.168.111.203

4. Check the new distribution of slots¶

$ redis-trib.rb check 192.168.111.201:18800 | grep master | grep slot
   slots:273-818 (546 slots) master
   slots:11742-12287 (546 slots) master
   slots:0-272,10650-10921,14198-14199 (547 slots) master
   slots:10922,11469-11741,14746-15018 (547 slots) master
   slots:6827-7372 (546 slots) master
   slots:1912-2457 (546 slots) master
   slots:6008-6553 (546 slots) master
   slots:7646-8191 (546 slots) master
   slots:1911,5734-6007,13926-14197 (547 slots) master
   slots:5188-5733 (546 slots) master
   slots:13380-13925 (546 slots) master
   slots:1092-1637 (546 slots) master
   slots:1638-1910,9830-10103 (547 slots) master
   slots:3550-4095 (546 slots) master
   slots:7373-7645,8192-8464 (546 slots) master
   slots:14200-14745 (546 slots) master
   slots:2458-2730,4096-4368 (546 slots) master
   slots:4369-4914 (546 slots) master
   slots:9284-9829 (546 slots) master
   slots:12561-13106 (546 slots) master
   slots:6554-6826,15565-15837 (546 slots) master
   slots:9011-9283,12288-12560 (546 slots) master
   slots:4915-5187,13107-13379 (546 slots) master
   slots:15019-15564 (546 slots) master
   slots:10923-11468 (546 slots) master
   slots:819-1091,3277-3549 (546 slots) master
   slots:8465-9010 (546 slots) master
   slots:2731-3276 (546 slots) master
   slots:15838-16383 (546 slots) master
   slots:10104-10649 (546 slots) master

5. Check the new distribution of redis-servers¶

$ fb check-distribution
check distribution of masters/slaves...
SERVER NAME     |   M   |   S
--------------------------------
192.168.111.201 |   10  |   10
192.168.111.202 |   10  |   10
192.168.111.203 |   10  |   10
--------------------------------
Total nodes     |   30  |   30