hsgao_water
hsgao_water

Redis集群创建

经过半个月的学习，自己总结了下Redis集群创建，以及相关的节点操作

因为这里主要使用redis-cluster的命令，所以选择redis5.0以上版本（5.0以下版本有些redis-cluster命令不支持，需要redis-ruby工具的支持）。

准备工作

下载redis5.0以上版本

解压

tar –zxvf redis-5.0.5.tar.gz

编译redis

cd redis-5.0.5

make

创建必要目录

mkdir /usr/local/reids

cp redis-server /usr/local/bin

cp redis-benchmark /usr/local/bin

cp redis-check-rdb /usr/local/bin

cp redis-sentinel /usr/local/bin

cp redis-cli /usr/local/bin

cp redis.conf /usr/local/bin

mkdir /usr/local/cluster/7000

mkdir /usr/local/cluster/7000/data

cp redis-5.0.5/redis.conf  /usr/local/cluster/7000/

编辑redis.conf

port:7000

cluster-enabled yes

cluster-config-file /usr/local/cluster/7000/data/node.conf

pidfile /var/run/redis_7000.pid

dir /usr/local/bin

同理创建7001、7002、8000、8001、8002

cp /usr/local/cluster/7000/ redis.conf /usr/local/cluster/7001

port:7001

cluster-enabled yes

cluster-config-file /usr/local/cluster/7001/data/node.conf

pidfile /var/run/redis_7001.pid

dir /usr/local/bin

…

创建集群节点

创建6个节点

redis-server ./cluster/7000/redis.conf &

redis-server ./cluster/7001/redis.conf &

redis-server ./cluster/7002/redis.conf &

edis-server ./cluster/8000/redis.conf &

redis-server ./cluster/8001/redis.conf &

redis-server ./cluster/8002/redis.conf &

使用客户端redis-cli查看集群状态

[root@centos7 cluster]# redis-cli -c -h 127.0.0.1 -p 7000

127.0.0.1:7000> cluster info

cluster_state:fail

cluster_slots_assigned:0

cluster_slots_ok:0

cluster_slots_pfail:0

cluster_slots_fail:0

cluster_known_nodes:1

cluster_size:0

cluster_current_epoch:0

cluster_my_epoch:0

cluster_stats_messages_sent:0

cluster_stats_messages_received:0

 

使用客户端redis-cli查看集群节点

127.0.0.1:7000> cluster nodes

fa96dbb2ea63f16f1bc8f8315386b183d8f77abf :7000@17000 myself,master - 0 0 0 connected

关联各个节点

[root@centos7 cluster]# redis-cli --cluster create 127.0.0.1:7000 127.0.0.1:7001 127.0.0.1:7002 127.0.0.1:8000 127.0.0.1:8001 127.0.0.1:8002  --cluster-replicas 1

>>> Performing hash slots allocation on 6 nodes...

Master[0] -> Slots 0 - 5460

Master[1] -> Slots 5461 - 10922

Master[2] -> Slots 10923 - 16383

Adding replica 127.0.0.1:8001 to 127.0.0.1:7000

Adding replica 127.0.0.1:8002 to 127.0.0.1:7001

Adding replica 127.0.0.1:8000 to 127.0.0.1:7002

>>> Trying to optimize slaves allocation for anti-affinity

[WARNING] Some slaves are in the same host as their master

M: fa96dbb2ea63f16f1bc8f8315386b183d8f77abf 127.0.0.1:7000

   slots:[0-5460] (5461 slots) master

M: c6f8c708f7be74280c15eb6e744c18c3fa697776 127.0.0.1:7001

   slots:[5461-10922] (5462 slots) master

M: 2205895bf212f0e6f02ea5d119c9ff5ddb4344e3 127.0.0.1:7002

   slots:[10923-16383] (5461 slots) master

S: f111aa110aa32a6ead47858131f9836747a8e5a4 127.0.0.1:8000

   replicates 2205895bf212f0e6f02ea5d119c9ff5ddb4344e3

S: 41359b81cd266c9faadb243bad979bbae0307a17 127.0.0.1:8001

   replicates fa96dbb2ea63f16f1bc8f8315386b183d8f77abf

S: 10c3ab97d14e90f688adaa3eb36165176d2996c4 127.0.0.1:8002

   replicates c6f8c708f7be74280c15eb6e744c18c3fa697776

Can I set the above configuration? (type 'yes' to accept):

键入：yes

>>> Nodes configuration updated

>>> Assign a different config epoch to each node

51117:M 20 Jul 2019 23:34:32.773 # configEpoch set to 1 via CLUSTER SET-CONFIG-EPOCH

51125:M 20 Jul 2019 23:34:32.773 # configEpoch set to 2 via CLUSTER SET-CONFIG-EPOCH

51133:M 20 Jul 2019 23:34:32.773 # configEpoch set to 3 via CLUSTER SET-CONFIG-EPOCH

51154:M 20 Jul 2019 23:34:32.774 # configEpoch set to 4 via CLUSTER SET-CONFIG-EPOCH

51162:M 20 Jul 2019 23:34:32.774 # configEpoch set to 5 via CLUSTER SET-CONFIG-EPOCH

51171:M 20 Jul 2019 23:34:32.774 # configEpoch set to 6 via CLUSTER SET-CONFIG-EPOCH

>>> Sending CLUSTER MEET messages to join the cluster

51117:M 20 Jul 2019 23:34:32.843 # IP address for this node updated to 127.0.0.1

51154:M 20 Jul 2019 23:34:32.868 # IP address for this node updated to 127.0.0.1

51162:M 20 Jul 2019 23:34:32.870 # IP address for this node updated to 127.0.0.1

51171:M 20 Jul 2019 23:34:32.871 # IP address for this node updated to 127.0.0.1

51125:M 20 Jul 2019 23:34:32.873 # IP address for this node updated to 127.0.0.1

51133:M 20 Jul 2019 23:34:32.877 # IP address for this node updated to 127.0.0.1

Waiting for the cluster to join

....51133:M 20 Jul 2019 23:34:37.793 # Cluster state changed: ok

 

51154:S 20 Jul 2019 23:34:37.810 * Before turning into a replica, using my master parameters to synthesize a cached master: I may be able to synchronize with the new master with just a partial transfer.

51154:S 20 Jul 2019 23:34:37.810 # Cluster state changed: ok

51162:S 20 Jul 2019 23:34:37.812 * Before turning into a replica, using my master parameters to synthesize a cached master: I may be able to synchronize with the new master with just a partial transfer.

51162:S 20 Jul 2019 23:34:37.812 # Cluster state changed: ok

51117:M 20 Jul 2019 23:34:37.815 # Cluster state changed: ok

51171:S 20 Jul 2019 23:34:37.816 * Before turning into a replica, using my master parameters to synthesize a cached master: I may be able to synchronize with the new master with just a partial transfer.

51171:S 20 Jul 2019 23:34:37.816 # Cluster state changed: ok

>>> Performing Cluster Check (using node 127.0.0.1:7000)

M: fa96dbb2ea63f16f1bc8f8315386b183d8f77abf 127.0.0.1:7000

   slots:[0-5460] (5461 slots) master

   1 additional replica(s)

M: c6f8c708f7be74280c15eb6e744c18c3fa697776 127.0.0.1:7001

   slots:[5461-10922] (5462 slots) master

   1 additional replica(s)

M: 2205895bf212f0e6f02ea5d119c9ff5ddb4344e3 127.0.0.1:7002

   slots:[10923-16383] (5461 slots) master

   1 additional replica(s)

S: 10c3ab97d14e90f688adaa3eb36165176d2996c4 127.0.0.1:8002

   slots: (0 slots) slave

   replicates c6f8c708f7be74280c15eb6e744c18c3fa697776

S: f111aa110aa32a6ead47858131f9836747a8e5a4 127.0.0.1:8000

   slots: (0 slots) slave

   replicates 2205895bf212f0e6f02ea5d119c9ff5ddb4344e3

S: 41359b81cd266c9faadb243bad979bbae0307a17 127.0.0.1:8001

   slots: (0 slots) slave

   replicates fa96dbb2ea63f16f1bc8f8315386b183d8f77abf

51125:M 20 Jul 2019 23:34:37.836 # Cluster state changed: ok

[OK] All nodes agree about slots configuration.

>>> Check for open slots...

>>> Check slots coverage...

[OK] All 16384 slots covered.

[root@centos7 cluster]# 51162:S 20 Jul 2019 23:34:38.138 * Connecting to MASTER 127.0.0.1:7000

51162:S 20 Jul 2019 23:34:38.138 * MASTER <-> REPLICA sync started

51162:S 20 Jul 2019 23:34:38.139 * Non blocking connect for SYNC fired the event.

51162:S 20 Jul 2019 23:34:38.139 * Master replied to PING, replication can continue...

51162:S 20 Jul 2019 23:34:38.139 * Trying a partial resynchronization (request 6e5530f70a818ca64770e0fbbebba6b551975566:1).

51117:M 20 Jul 2019 23:34:38.139 * Replica 127.0.0.1:8001 asks for synchronization

51117:M 20 Jul 2019 23:34:38.139 * Partial resynchronization not accepted: Replication ID mismatch (Replica asked for '6e5530f70a818ca64770e0fbbebba6b551975566', my replication IDs are '512a0e3fc18ac6c82e17facdb2a87b53eff3428e' and '0000000000000000000000000000000000000000')

51117:M 20 Jul 2019 23:34:38.139 * Starting BGSAVE for SYNC with target: disk

51117:M 20 Jul 2019 23:34:38.140 * Background saving started by pid 51674

51162:S 20 Jul 2019 23:34:38.140 * Full resync from master: e0e7c98ac2f10cc90e941eeb072c9f6c214dc3db:0

51162:S 20 Jul 2019 23:34:38.140 * Discarding previously cached master state.

51674:C 20 Jul 2019 23:34:38.142 * DB saved on disk

51674:C 20 Jul 2019 23:34:38.142 * RDB: 2 MB of memory used by copy-on-write

51154:S 20 Jul 2019 23:34:38.194 * Connecting to MASTER 127.0.0.1:7002

51154:S 20 Jul 2019 23:34:38.194 * MASTER <-> REPLICA sync started

51154:S 20 Jul 2019 23:34:38.194 * Non blocking connect for SYNC fired the event.

51154:S 20 Jul 2019 23:34:38.194 * Master replied to PING, replication can continue...

51154:S 20 Jul 2019 23:34:38.194 * Trying a partial resynchronization (request 7b8d7e52220026011c44e8764a69da4356d5d9ee:1).

51133:M 20 Jul 2019 23:34:38.194 * Replica 127.0.0.1:8000 asks for synchronization

51133:M 20 Jul 2019 23:34:38.194 * Partial resynchronization not accepted: Replication ID mismatch (Replica asked for '7b8d7e52220026011c44e8764a69da4356d5d9ee', my replication IDs are 'caf5671ce79d2942ed5e58389fc4eb2277d0e075' and '0000000000000000000000000000000000000000')

51133:M 20 Jul 2019 23:34:38.194 * Starting BGSAVE for SYNC with target: disk

51133:M 20 Jul 2019 23:34:38.195 * Background saving started by pid 51675

51154:S 20 Jul 2019 23:34:38.196 * Full resync from master: be79475f78131e9c067b4d0c765925ad30f89819:0

51154:S 20 Jul 2019 23:34:38.196 * Discarding previously cached master state.

51675:C 20 Jul 2019 23:34:38.198 * DB saved on disk

51675:C 20 Jul 2019 23:34:38.199 * RDB: 4 MB of memory used by copy-on-write

51117:M 20 Jul 2019 23:34:38.219 * Background saving terminated with success

51117:M 20 Jul 2019 23:34:38.219 * Synchronization with replica 127.0.0.1:8001 succeeded

51162:S 20 Jul 2019 23:34:38.219 * MASTER <-> REPLICA sync: receiving 175 bytes from master

51162:S 20 Jul 2019 23:34:38.220 * MASTER <-> REPLICA sync: Flushing old data

51162:S 20 Jul 2019 23:34:38.220 * MASTER <-> REPLICA sync: Loading DB in memory

51162:S 20 Jul 2019 23:34:38.220 * MASTER <-> REPLICA sync: Finished with success

51162:S 20 Jul 2019 23:34:38.221 * Background append only file rewriting started by pid 51676

51162:S 20 Jul 2019 23:34:38.262 * AOF rewrite child asks to stop sending diffs.

51676:C 20 Jul 2019 23:34:38.263 * Parent agreed to stop sending diffs. Finalizing AOF...

51676:C 20 Jul 2019 23:34:38.263 * Concatenating 0.00 MB of AOF diff received from parent.

51676:C 20 Jul 2019 23:34:38.263 * SYNC append only file rewrite performed

51676:C 20 Jul 2019 23:34:38.265 * AOF rewrite: 4 MB of memory used by copy-on-write

51133:M 20 Jul 2019 23:34:38.296 * Background saving terminated with success

51133:M 20 Jul 2019 23:34:38.296 * Synchronization with replica 127.0.0.1:8000 succeeded

51154:S 20 Jul 2019 23:34:38.297 * MASTER <-> REPLICA sync: receiving 175 bytes from master

51154:S 20 Jul 2019 23:34:38.297 * MASTER <-> REPLICA sync: Flushing old data

51154:S 20 Jul 2019 23:34:38.297 * MASTER <-> REPLICA sync: Loading DB in memory

51154:S 20 Jul 2019 23:34:38.297 * MASTER <-> REPLICA sync: Finished with success

51154:S 20 Jul 2019 23:34:38.299 * Background append only file rewriting started by pid 51677

51162:S 20 Jul 2019 23:34:38.340 * Background AOF rewrite terminated with success

51162:S 20 Jul 2019 23:34:38.340 * Residual parent diff successfully flushed to the rewritten AOF (0.00 MB)

51162:S 20 Jul 2019 23:34:38.340 * Background AOF rewrite finished successfully

51154:S 20 Jul 2019 23:34:38.348 * AOF rewrite child asks to stop sending diffs.

51677:C 20 Jul 2019 23:34:38.348 * Parent agreed to stop sending diffs. Finalizing AOF...

51677:C 20 Jul 2019 23:34:38.348 * Concatenating 0.00 MB of AOF diff received from parent.

51677:C 20 Jul 2019 23:34:38.349 * SYNC append only file rewrite performed

51677:C 20 Jul 2019 23:34:38.350 * AOF rewrite: 4 MB of memory used by copy-on-write

51154:S 20 Jul 2019 23:34:38.397 * Background AOF rewrite terminated with success

51154:S 20 Jul 2019 23:34:38.397 * Residual parent diff successfully flushed to the rewritten AOF (0.00 MB)

51154:S 20 Jul 2019 23:34:38.397 * Background AOF rewrite finished successfully

51171:S 20 Jul 2019 23:34:38.499 * Connecting to MASTER 127.0.0.1:7001

51171:S 20 Jul 2019 23:34:38.501 * MASTER <-> REPLICA sync started

51171:S 20 Jul 2019 23:34:38.502 * Non blocking connect for SYNC fired the event.

51171:S 20 Jul 2019 23:34:38.505 * Master replied to PING, replication can continue...

51171:S 20 Jul 2019 23:34:38.506 * Trying a partial resynchronization (request 3338a75734915ae4ac66f8d92c397586269c580b:1).

51125:M 20 Jul 2019 23:34:38.507 * Replica 127.0.0.1:8002 asks for synchronization

51125:M 20 Jul 2019 23:34:38.507 * Partial resynchronization not accepted: Replication ID mismatch (Replica asked for '3338a75734915ae4ac66f8d92c397586269c580b', my replication IDs are '93d42b1d560f630f03fe372c1b6e7871b3ffb3a9' and '0000000000000000000000000000000000000000')

51125:M 20 Jul 2019 23:34:38.507 * Starting BGSAVE for SYNC with target: disk

51125:M 20 Jul 2019 23:34:38.509 * Background saving started by pid 51679

51171:S 20 Jul 2019 23:34:38.510 * Full resync from master: 0937b53a5c14f0a112afb9256cadd43540433963:0

51171:S 20 Jul 2019 23:34:38.510 * Discarding previously cached master state.

51679:C 20 Jul 2019 23:34:38.516 * DB saved on disk

51679:C 20 Jul 2019 23:34:38.519 * RDB: 2 MB of memory used by copy-on-write

51125:M 20 Jul 2019 23:34:38.544 * Background saving terminated with success

51125:M 20 Jul 2019 23:34:38.544 * Synchronization with replica 127.0.0.1:8002 succeeded

51171:S 20 Jul 2019 23:34:38.544 * MASTER <-> REPLICA sync: receiving 175 bytes from master

51171:S 20 Jul 2019 23:34:38.545 * MASTER <-> REPLICA sync: Flushing old data

51171:S 20 Jul 2019 23:34:38.545 * MASTER <-> REPLICA sync: Loading DB in memory

51171:S 20 Jul 2019 23:34:38.545 * MASTER <-> REPLICA sync: Finished with success

51171:S 20 Jul 2019 23:34:38.547 * Background append only file rewriting started by pid 51680

51171:S 20 Jul 2019 23:34:38.590 * AOF rewrite child asks to stop sending diffs.

51680:C 20 Jul 2019 23:34:38.590 * Parent agreed to stop sending diffs. Finalizing AOF...

51680:C 20 Jul 2019 23:34:38.591 * Concatenating 0.00 MB of AOF diff received from parent.

51680:C 20 Jul 2019 23:34:38.592 * SYNC append only file rewrite performed

51680:C 20 Jul 2019 23:34:38.594 * AOF rewrite: 4 MB of memory used by copy-on-write

51171:S 20 Jul 2019 23:34:38.602 * Background AOF rewrite terminated with success

51171:S 20 Jul 2019 23:34:38.602 * Residual parent diff successfully flushed to the rewritten AOF (0.00 MB)

51171:S 20 Jul 2019 23:34:38.603 * Background AOF rewrite finished successfully

 

集群创建成功，使用客户端redis-cli查看集群状态

[root@centos7 cluster]# redis-cli -c -h 127.0.0.1 -p 7000

127.0.0.1:7000> cluster info

cluster_state:ok

cluster_slots_assigned:16384

cluster_slots_ok:16384

cluster_slots_pfail:0

cluster_slots_fail:0

cluster_known_nodes:6

cluster_size:3

cluster_current_epoch:6

cluster_my_epoch:1

cluster_stats_messages_ping_sent:115

cluster_stats_messages_pong_sent:118

cluster_stats_messages_sent:233

cluster_stats_messages_ping_received:113

cluster_stats_messages_pong_received:115

cluster_stats_messages_meet_received:5

cluster_stats_messages_received:233

 

查看节点信息

127.0.0.1:7000> cluster nodes

c6f8c708f7be74280c15eb6e744c18c3fa697776 127.0.0.1:7001@17001 master - 0 1563680220000 2 connected 5461-10922

2205895bf212f0e6f02ea5d119c9ff5ddb4344e3 127.0.0.1:7002@17002 master - 0 1563680223000 3 connected 10923-16383

10c3ab97d14e90f688adaa3eb36165176d2996c4 127.0.0.1:8002@18002 slave c6f8c708f7be74280c15eb6e744c18c3fa697776 0 1563680221983 6 connected

f111aa110aa32a6ead47858131f9836747a8e5a4 127.0.0.1:8000@18000 slave 2205895bf212f0e6f02ea5d119c9ff5ddb4344e3 0 1563680220973 4 connected

41359b81cd266c9faadb243bad979bbae0307a17 127.0.0.1:8001@18001 slave fa96dbb2ea63f16f1bc8f8315386b183d8f77abf 0 1563680221000 5 connected

fa96dbb2ea63f16f1bc8f8315386b183d8f77abf 127.0.0.1:7000@17000 myself,master - 0 1563680222000 1 connected 0-5460

 

 

添加主节点

 

将节点7003加入到集群中

[root@centos7 cluster]# redis-cli --cluster add-node 127.0.0.1:7003 127.0.0.1:7000

>>> Adding node 127.0.0.1:7003 to cluster 127.0.0.1:7000

>>> Performing Cluster Check (using node 127.0.0.1:7000)

M: fa96dbb2ea63f16f1bc8f8315386b183d8f77abf 127.0.0.1:7000

   slots:[0-5460] (5461 slots) master

   1 additional replica(s)

S: c6f8c708f7be74280c15eb6e744c18c3fa697776 127.0.0.1:7001

   slots: (0 slots) slave

   replicates 10c3ab97d14e90f688adaa3eb36165176d2996c4

S: 2205895bf212f0e6f02ea5d119c9ff5ddb4344e3 127.0.0.1:7002

   slots: (0 slots) slave

   replicates f111aa110aa32a6ead47858131f9836747a8e5a4

M: 10c3ab97d14e90f688adaa3eb36165176d2996c4 127.0.0.1:8002

   slots:[5461-10922] (5462 slots) master

   1 additional replica(s)

M: f111aa110aa32a6ead47858131f9836747a8e5a4 127.0.0.1:8000

   slots:[10923-16383] (5461 slots) master

   1 additional replica(s)

S: 41359b81cd266c9faadb243bad979bbae0307a17 127.0.0.1:8001

   slots: (0 slots) slave

   replicates fa96dbb2ea63f16f1bc8f8315386b183d8f77abf

[OK] All nodes agree about slots configuration.

>>> Check for open slots...

>>> Check slots coverage...

[OK] All 16384 slots covered.

>>> Send CLUSTER MEET to node 127.0.0.1:7003 to make it join the cluster.

[OK] New node added correctly.

 

 

查看集群状态

[root@centos7 cluster]# redis-cli -p 7000

127.0.0.1:7000> cluster info

cluster_state:ok

cluster_slots_assigned:16384

cluster_slots_ok:16384

cluster_slots_pfail:0

cluster_slots_fail:0

cluster_known_nodes:7

cluster_size:3

cluster_current_epoch:8

cluster_my_epoch:1

cluster_stats_messages_ping_sent:8101

cluster_stats_messages_pong_sent:8420

cluster_stats_messages_auth-ack_sent:2

cluster_stats_messages_update_sent:1

cluster_stats_messages_sent:16524

cluster_stats_messages_ping_received:8414

cluster_stats_messages_pong_received:8098

cluster_stats_messages_meet_received:6

cluster_stats_messages_fail_received:2

cluster_stats_messages_auth-req_received:2

cluster_stats_messages_received:16522

 

查看节点信息，

新加入的7003为主节点，没有分配槽

127.0.0.1:7000> cluster nodes

c6f8c708f7be74280c15eb6e744c18c3fa697776 127.0.0.1:7001@17001 slave 10c3ab97d14e90f688adaa3eb36165176d2996c4 0 1563690713000 8 connected

2205895bf212f0e6f02ea5d119c9ff5ddb4344e3 127.0.0.1:7002@17002 slave f111aa110aa32a6ead47858131f9836747a8e5a4 0 1563690713617 7 connected

10c3ab97d14e90f688adaa3eb36165176d2996c4 127.0.0.1:8002@18002 master - 0 1563690715660 8 connected 5461-10922

f111aa110aa32a6ead47858131f9836747a8e5a4 127.0.0.1:8000@18000 master - 0 1563690714000 7 connected 10923-16383

41359b81cd266c9faadb243bad979bbae0307a17 127.0.0.1:8001@18001 slave fa96dbb2ea63f16f1bc8f8315386b183d8f77abf 0 1563690710000 5 connected

fa96dbb2ea63f16f1bc8f8315386b183d8f77abf 127.0.0.1:7000@17000 myself,master - 0 1563690715000 1 connected 0-5460

3dfb41469d6da4b3d215e4f85a7b0e7fba67cd57 127.0.0.1:7003@17003 master - 0 1563690714644 0 connected

 

为节点7003分配槽，这里我们分配1000个槽

 

[root@centos7 cluster]# redis-cli --cluster reshard 127.0.0.1:7003

>>> Performing Cluster Check (using node 127.0.0.1:7003)

M: 3dfb41469d6da4b3d215e4f85a7b0e7fba67cd57 127.0.0.1:7003

   slots: (0 slots) master

S: 2205895bf212f0e6f02ea5d119c9ff5ddb4344e3 127.0.0.1:7002

   slots: (0 slots) slave

   replicates f111aa110aa32a6ead47858131f9836747a8e5a4

M: 10c3ab97d14e90f688adaa3eb36165176d2996c4 127.0.0.1:8002

   slots:[5461-10922] (5462 slots) master

   1 additional replica(s)

S: c6f8c708f7be74280c15eb6e744c18c3fa697776 127.0.0.1:7001

   slots: (0 slots) slave

   replicates 10c3ab97d14e90f688adaa3eb36165176d2996c4

M: fa96dbb2ea63f16f1bc8f8315386b183d8f77abf 127.0.0.1:7000

   slots:[0-5460] (5461 slots) master

   1 additional replica(s)

M: f111aa110aa32a6ead47858131f9836747a8e5a4 127.0.0.1:8000

   slots:[10923-16383] (5461 slots) master

   1 additional replica(s)

S: 41359b81cd266c9faadb243bad979bbae0307a17 127.0.0.1:8001

   slots: (0 slots) slave

   replicates fa96dbb2ea63f16f1bc8f8315386b183d8f77abf

[OK] All nodes agree about slots configuration.

>>> Check for open slots...

>>> Check slots coverage...

[OK] All 16384 slots covered.

How many slots do you want to move (from 1 to 16384)?

 

要分配多少个槽，这里我们选择1000个槽

 

How many slots do you want to move (from 1 to 16384)? 1000

What is the receiving node ID?

接受槽的节点ID，也就是新增节点7003的ID：3dfb41469d6da4b3d215e4f85a7b0e7fba67cd57

 

What is the receiving node ID? 3dfb41469d6da4b3d215e4f85a7b0e7fba67cd57

Please enter all the source node IDs.

  Type 'all' to use all the nodes as source nodes for the hash slots.

  Type 'done' once you entered all the source nodes IDs.

Source node #1:

 

第一个源节点id，也就是我们要引入槽所在的节点id，这里我们先填入节点7000的id：fa96dbb2ea63f16f1bc8f8315386b183d8f77abf

 

Source node #1: fa96dbb2ea63f16f1bc8f8315386b183d8f77abf

Source node #2:

第二个源节点id，我们填入节点8000的id：f111aa110aa32a6ead47858131f9836747a8e5a4

 

Source node #2: f111aa110aa32a6ead47858131f9836747a8e5a4

Source node #3:

 

第三个源节点id，我们填入节点8002的id：10c3ab97d14e90f688adaa3eb36165176d2996c4

Source node #3: 10c3ab97d14e90f688adaa3eb36165176d2996c4

Source node #4:

这里提示第四个节点id，其实我们只有三个主节点，所以槽的来源最多也只能是3个节点了，所以我填入done，让服务器开始分配槽

 

Source node #4:done

Ready to move 1000 slots.

  Source nodes:

    M: fa96dbb2ea63f16f1bc8f8315386b183d8f77abf 127.0.0.1:7000

       slots:[0-5460] (5461 slots) master

       1 additional replica(s)

    M: f111aa110aa32a6ead47858131f9836747a8e5a4 127.0.0.1:8000

       slots:[10923-16383] (5461 slots) master

       1 additional replica(s)

    M: 10c3ab97d14e90f688adaa3eb36165176d2996c4 127.0.0.1:8002

       slots:[5461-10922] (5462 slots) master

       1 additional replica(s)

  Destination node:

    M: 3dfb41469d6da4b3d215e4f85a7b0e7fba67cd57 127.0.0.1:7003

       slots: (0 slots) master

  Resharding plan:

    Moving slot 5461 from 10c3ab97d14e90f688adaa3eb36165176d2996c4

    Moving slot 5462 from 10c3ab97d14e90f688adaa3eb36165176d2996c4

    Moving slot 5463 from 10c3ab97d14e90f688adaa3eb36165176d2996c4

    Moving slot 5464 from 10c3ab97d14e90f688adaa3eb36165176d2996c4

    Moving slot 5465 from 10c3ab97d14e90f688adaa3eb36165176d2996c4

    Moving slot 5466 from 10c3ab97d14e90f688adaa3eb36165176d2996c4

    Moving slot 5467 from 10c3ab97d14e90f688adaa3eb36165176d2996c4

Moving slot 5468 from 10c3ab97d14e90f688adaa3eb36165176d2996c4

….

   Moving slot 11255 from f111aa110aa32a6ead47858131f9836747a8e5a4

Do you want to proceed with the proposed reshard plan (yes/no)?

 

最后确认执行分配计划，yes

Moving slot 5461 from 127.0.0.1:8002 to 127.0.0.1:7003:

Moving slot 5462 from 127.0.0.1:8002 to 127.0.0.1:7003:

Moving slot 5463 from 127.0.0.1:8002 to 127.0.0.1:7003:

Moving slot 5464 from 127.0.0.1:8002 to 127.0.0.1:7003:

…

我们发现节点7000 ,节点8000 节点8002   不断的迁移槽到节点7003上

槽已经重新分配完了，我们执行cluster info查看节点状态

[root@centos7 cluster]# redis-cli -p 7000

127.0.0.1:7000> cluster info

cluster_state:ok

cluster_slots_assigned:16384

cluster_slots_ok:16384

cluster_slots_pfail:0

cluster_slots_fail:0

cluster_known_nodes:7

cluster_size:4

cluster_current_epoch:9

cluster_my_epoch:1

cluster_stats_messages_ping_sent:9511

cluster_stats_messages_pong_sent:9842

cluster_stats_messages_auth-ack_sent:2

cluster_stats_messages_update_sent:8

cluster_stats_messages_sent:19363

cluster_stats_messages_ping_received:9836

cluster_stats_messages_pong_received:9508

cluster_stats_messages_meet_received:6

cluster_stats_messages_fail_received:2

cluster_stats_messages_auth-req_received:2

cluster_stats_messages_received:19354

 

查看节点信息 cluster nodes

 

127.0.0.1:7000> cluster nodes

c6f8c708f7be74280c15eb6e744c18c3fa697776 127.0.0.1:7001@17001 slave 10c3ab97d14e90f688adaa3eb36165176d2996c4 0 1563692116650 8 connected

2205895bf212f0e6f02ea5d119c9ff5ddb4344e3 127.0.0.1:7002@17002 slave f111aa110aa32a6ead47858131f9836747a8e5a4 0 1563692113000 7 connected

10c3ab97d14e90f688adaa3eb36165176d2996c4 127.0.0.1:8002@18002 master - 0 1563692115000 8 connected 5795-10922

f111aa110aa32a6ead47858131f9836747a8e5a4 127.0.0.1:8000@18000 master - 0 1563692114000 7 connected 11256-16383

41359b81cd266c9faadb243bad979bbae0307a17 127.0.0.1:8001@18001 slave fa96dbb2ea63f16f1bc8f8315386b183d8f77abf 0 1563692112000 5 connected

fa96dbb2ea63f16f1bc8f8315386b183d8f77abf 127.0.0.1:7000@17000 myself,master - 0 1563692112000 1 connected 333-5460

3dfb41469d6da4b3d215e4f85a7b0e7fba67cd57 127.0.0.1:7003@17003 master - 0 1563692115643 9 connected 0-332 5461-5794 10923-11255

 

至此，我们发现槽0-332 5461-5794 10923-11255分配给了新节点7003

 

添加从节点

 

添加节点8003，作为7003的从节点

 

  1. 方案一：

 [root@centos7 cluster]# redis-cli --cluster add-node 127.0.0.1:8003 127.0.0.1:7003 --cluster-slave

>>> Adding node 127.0.0.1:8003 to cluster 127.0.0.1:7003

>>> Performing Cluster Check (using node 127.0.0.1:7003)

M: 3dfb41469d6da4b3d215e4f85a7b0e7fba67cd57 127.0.0.1:7003

   slots:[0-332],[5461-5794],[10923-11255] (1000 slots) master

S: 2205895bf212f0e6f02ea5d119c9ff5ddb4344e3 127.0.0.1:7002

   slots: (0 slots) slave

   replicates f111aa110aa32a6ead47858131f9836747a8e5a4

M: 10c3ab97d14e90f688adaa3eb36165176d2996c4 127.0.0.1:8002

   slots:[5795-10922] (5128 slots) master

   1 additional replica(s)

S: c6f8c708f7be74280c15eb6e744c18c3fa697776 127.0.0.1:7001

   slots: (0 slots) slave

   replicates 10c3ab97d14e90f688adaa3eb36165176d2996c4

M: fa96dbb2ea63f16f1bc8f8315386b183d8f77abf 127.0.0.1:7000

   slots:[333-5460] (5128 slots) master

   1 additional replica(s)

M: f111aa110aa32a6ead47858131f9836747a8e5a4 127.0.0.1:8000

   slots:[11256-16383] (5128 slots) master

   1 additional replica(s)

S: 41359b81cd266c9faadb243bad979bbae0307a17 127.0.0.1:8001

   slots: (0 slots) slave

   replicates fa96dbb2ea63f16f1bc8f8315386b183d8f77abf

[OK] All nodes agree about slots configuration.

>>> Check for open slots...

>>> Check slots coverage...

[OK] All 16384 slots covered.

Automatically selected master 127.0.0.1:7003

>>> Send CLUSTER MEET to node 127.0.0.1:8003 to make it join the cluster.

Waiting for the cluster to join

 

>>> Configure node as replica of 127.0.0.1:7003.

[OK] New node added correctly.

 

 

查看节点状态信息

 

[root@centos7 cluster]# redis-cli -p 7000

127.0.0.1:7000> cluster info

cluster_state:ok

cluster_slots_assigned:16384

cluster_slots_ok:16384

cluster_slots_pfail:0

cluster_slots_fail:0

cluster_known_nodes:8

cluster_size:4

cluster_current_epoch:9

cluster_my_epoch:1

cluster_stats_messages_ping_sent:9914

cluster_stats_messages_pong_sent:10246

cluster_stats_messages_meet_sent:1

cluster_stats_messages_auth-ack_sent:2

cluster_stats_messages_update_sent:8

cluster_stats_messages_sent:20171

cluster_stats_messages_ping_received:10239

cluster_stats_messages_pong_received:9912

cluster_stats_messages_meet_received:7

cluster_stats_messages_fail_received:2

cluster_stats_messages_auth-req_received:2

cluster_stats_messages_received:20162

 

查看节点信息

127.0.0.1:7000> cluster nodes

624565cbe3905c214b8607f6b64d469e100c8683 127.0.0.1:8003@18003 slave 3dfb41469d6da4b3d215e4f85a7b0e7fba67cd57 0 1563692540000 9 connected

2205895bf212f0e6f02ea5d119c9ff5ddb4344e3 127.0.0.1:7002@17002 slave f111aa110aa32a6ead47858131f9836747a8e5a4 0 1563692541000 7 connected

10c3ab97d14e90f688adaa3eb36165176d2996c4 127.0.0.1:8002@18002 master - 0 1563692537815 8 connected 5795-10922

fa96dbb2ea63f16f1bc8f8315386b183d8f77abf 127.0.0.1:7000@17000 myself,master - 0 1563692537000 1 connected 333-5460

3dfb41469d6da4b3d215e4f85a7b0e7fba67cd57 127.0.0.1:7003@17003 master - 0 1563692541868 9 connected 0-332 5461-5794 10923-11255

c6f8c708f7be74280c15eb6e744c18c3fa697776 127.0.0.1:7001@17001 slave 10c3ab97d14e90f688adaa3eb36165176d2996c4 0 1563692539851 8 connected

41359b81cd266c9faadb243bad979bbae0307a17 127.0.0.1:8001@18001 slave fa96dbb2ea63f16f1bc8f8315386b183d8f77abf 0 1563692538000 5 connected

f111aa110aa32a6ead47858131f9836747a8e5a4 127.0.0.1:8000@18000 master - 0 1563692540857 7 connected 11256-16383

 

至此，我们发现节点8003已经为7003的从节点

 

分析：

redis-cli –cluster add-node ip:port clusertip:clusterport –cluster-slave

这个命令会将节点ip:port随机添加到集群中的任何一个节点，而不是确定的节点，所以要确定成为某个节点的主节点，必须使用以下命令

 

  1. 方案二

redis-cli –cluster add-node addIp:addPort clustertIp:clusterPort –cluster-slave –cluster-master-id

例如上文将8003节点作为7003的从节点，可以使用命令

redis-cli –cluster add-node 127.0.0.1:8003 127.0.0.1:7000 –cluster-slave –cluster-master-id 3dfb41469d6da4b3d215e4f85a7b0e7fba67cd57

 

方案三

 

将新节点作为主节点加入到集群中

Redis-cli –cluster add-node addip:addport clusterip:clusertport

 

然后连接到节点

Redis-cli –c –h -p

 

指定新节点为某个节点的从节点

cluster replicate master-id

 

例如：我们添加节点8004，作为7000的从节点

redis-cli --cluster add-node 127.0.0.1:8004 127.0.0.1:7000

>>> Adding node 127.0.0.1:8004 to cluster 127.0.0.1:7000

>>> Performing Cluster Check (using node 127.0.0.1:7000)

M: fa96dbb2ea63f16f1bc8f8315386b183d8f77abf 127.0.0.1:7000

   slots:[333-5460] (5128 slots) master

   1 additional replica(s)

S: 624565cbe3905c214b8607f6b64d469e100c8683 127.0.0.1:8003

   slots: (0 slots) slave

   replicates 3dfb41469d6da4b3d215e4f85a7b0e7fba67cd57

S: 2205895bf212f0e6f02ea5d119c9ff5ddb4344e3 127.0.0.1:7002

   slots: (0 slots) slave

   replicates f111aa110aa32a6ead47858131f9836747a8e5a4

M: 10c3ab97d14e90f688adaa3eb36165176d2996c4 127.0.0.1:8002

   slots:[5795-10922] (5128 slots) master

   1 additional replica(s)

M: 3dfb41469d6da4b3d215e4f85a7b0e7fba67cd57 127.0.0.1:7003

   slots:[0-332],[5461-5794],[10923-11255] (1000 slots) master

   1 additional replica(s)

S: c6f8c708f7be74280c15eb6e744c18c3fa697776 127.0.0.1:7001

   slots: (0 slots) slave

   replicates 10c3ab97d14e90f688adaa3eb36165176d2996c4

S: 41359b81cd266c9faadb243bad979bbae0307a17 127.0.0.1:8001

   slots: (0 slots) slave

   replicates fa96dbb2ea63f16f1bc8f8315386b183d8f77abf

M: f111aa110aa32a6ead47858131f9836747a8e5a4 127.0.0.1:8000

   slots:[11256-16383] (5128 slots) master

   1 additional replica(s)

[OK] All nodes agree about slots configuration.

>>> Check for open slots...

>>> Check slots coverage...

[OK] All 16384 slots covered.

>>> Send CLUSTER MEET to node 127.0.0.1:8004 to make it join the cluster.

[OK] New node added correctly.

[root@centos7 cluster]# 61776:M 21 Jul 2019 03:25:24.548 # IP address for this node updated to 127.0.0.1

61776:M 21 Jul 2019 03:25:29.629 # Cluster state changed: ok

 

查看节点8004，此时节点8004为未分配槽的主节点

redis-cli -p 7000

127.0.0.1:7000> cluster-nodes

(error) ERR unknown command `cluster-nodes`, with args beginning with:

127.0.0.1:7000> cluster nodes

624565cbe3905c214b8607f6b64d469e100c8683 127.0.0.1:8003@18003 slave 3dfb41469d6da4b3d215e4f85a7b0e7fba67cd57 0 1563694000370 9 connected

2205895bf212f0e6f02ea5d119c9ff5ddb4344e3 127.0.0.1:7002@17002 slave f111aa110aa32a6ead47858131f9836747a8e5a4 0 1563693998339 7 connected

707d49c11fb1d7ccc7f8b8ea183a8e0261b4166a 127.0.0.1:8004@18004 master - 0 1563693997320 0 connected

10c3ab97d14e90f688adaa3eb36165176d2996c4 127.0.0.1:8002@18002 master - 0 1563693996000 8 connected 5795-10922

fa96dbb2ea63f16f1bc8f8315386b183d8f77abf 127.0.0.1:7000@17000 myself,master - 0 1563693993000 1 connected 333-5460

3dfb41469d6da4b3d215e4f85a7b0e7fba67cd57 127.0.0.1:7003@17003 master - 0 1563693999355 9 connected 0-332 5461-5794 10923-11255

c6f8c708f7be74280c15eb6e744c18c3fa697776 127.0.0.1:7001@17001 slave 10c3ab97d14e90f688adaa3eb36165176d2996c4 0 1563693996000 8 connected

41359b81cd266c9faadb243bad979bbae0307a17 127.0.0.1:8001@18001 slave fa96dbb2ea63f16f1bc8f8315386b183d8f77abf 0 1563693997000 5 connected

f111aa110aa32a6ead47858131f9836747a8e5a4 127.0.0.1:8000@18000 master - 0 1563693997000 7 connected 11256-16383

 

将主节点8004作为7000的从节点

[root@centos7 cluster]# redis-cli -p 8004

127.0.0.1:8004> cluster replicate fa96dbb2ea63f16f1bc8f8315386b183d8f77abf

61776:S 21 Jul 2019 03:28:51.738 * Before turning into a replica, using my master parameters to synthesize a cached master: I may be able to synchronize with the new master with just a partial transfer.

OK

127.0.0.1:8004> 61776:S 21 Jul 2019 03:28:52.199 * Connecting to MASTER 127.0.0.1:7000

                                                                                      61776:S 21 Jul 2019 03:28:52.199 * MASTER <-> REPLICA sync started

               61776:S 21 Jul 2019 03:28:52.199 * Non blocking connect for SYNC fired the event.

                                                                                                61776:S 21 Jul 2019 03:28:52.201 * Master replied to PING, replication can continue...

                                             61776:S 21 Jul 2019 03:28:52.202 * Trying a partial resynchronization (request 78bffb5248811bafcd4e4308a6e42a9cc8447587:1).

                               61776:S 21 Jul 2019 03:28:52.333 * Full resync from master: e0e7c98ac2f10cc90e941eeb072c9f6c214dc3db:16044

                                                                                                                                        61776:S 21 Jul 2019 03:28:52.333 * Discarding previously cached master state.

                                                                            61776:S 21 Jul 2019 03:28:52.333 * MASTER <-> REPLICA sync: receiving 176 bytes from master

                              61776:S 21 Jul 2019 03:28:52.333 * MASTER <-> REPLICA sync: Flushing old data

                                                                                                           61776:S 21 Jul 2019 03:28:52.333 * MASTER <-> REPLICA sync: Loading DB in memory

                                                  61776:S 21 Jul 2019 03:28:52.333 * MASTER <-> REPLICA sync: Finished with success

                                                                                                                                   61776:S 21 Jul 2019 03:28:52.334 * Background append only file rewriting started by pid 62404

                                                                                       61776:S 21 Jul 2019 03:28:52.388 * AOF rewrite child asks to stop sending diffs.

                              62404:C 21 Jul 2019 03:28:52.389 * Parent agreed to stop sending diffs. Finalizing AOF...

                                                                                                                       62404:C 21 Jul 2019 03:28:52.389 * Concatenating 0.00 MB of AOF diff received from parent.

                                                                        62404:C 21 Jul 2019 03:28:52.389 * SYNC append only file rewrite performed

         62404:C 21 Jul 2019 03:28:52.389 * AOF rewrite: 4 MB of memory used by copy-on-write

                                                                                             61776:S 21 Jul 2019 03:28:52.415 * Background AOF rewrite terminated with success

                                     61776:S 21 Jul 2019 03:28:52.415 * Residual parent diff successfully flushed to the rewritten AOF (0.00 MB)

       61776:S 21 Jul 2019 03:28:52.415 * Background AOF rewrite finished successfully

 

查看节点信息

[root@centos7 cluster]# redis-cli -p 7000

127.0.0.1:7000> cluster nodes

624565cbe3905c214b8607f6b64d469e100c8683 127.0.0.1:8003@18003 slave 3dfb41469d6da4b3d215e4f85a7b0e7fba67cd57 0 1563694180753 9 connected

2205895bf212f0e6f02ea5d119c9ff5ddb4344e3 127.0.0.1:7002@17002 slave f111aa110aa32a6ead47858131f9836747a8e5a4 0 1563694180000 7 connected

707d49c11fb1d7ccc7f8b8ea183a8e0261b4166a 127.0.0.1:8004@18004 slave fa96dbb2ea63f16f1bc8f8315386b183d8f77abf 0 1563694177713 1 connected

10c3ab97d14e90f688adaa3eb36165176d2996c4 127.0.0.1:8002@18002 master - 0 1563694178000 8 connected 5795-10922

fa96dbb2ea63f16f1bc8f8315386b183d8f77abf 127.0.0.1:7000@17000 myself,master - 0 1563694178000 1 connected 333-5460

3dfb41469d6da4b3d215e4f85a7b0e7fba67cd57 127.0.0.1:7003@17003 master - 0 1563694179742 9 connected 0-332 5461-5794 10923-11255

c6f8c708f7be74280c15eb6e744c18c3fa697776 127.0.0.1:7001@17001 slave 10c3ab97d14e90f688adaa3eb36165176d2996c4 0 1563694181762 8 connected

41359b81cd266c9faadb243bad979bbae0307a17 127.0.0.1:8001@18001 slave fa96dbb2ea63f16f1bc8f8315386b183d8f77abf 0 1563694177000 5 connected

f111aa110aa32a6ead47858131f9836747a8e5a4 127.0.0.1:8000@18000 master - 0 1563694179000 7 connected 11256-16383

 

至此，我们发现8004已经为7000的从节点

 

 

删除从节点

Redis-cli –cluster del-node clusterip:clusterport del-id

因为从节点上没有分配槽，所以可以直接删除

 

例如删除从节点8004

[root@centos7 cluster]# redis-cli --cluster del-node 127.0.0.1:8004 fa96dbb2ea63f16f1bc8f8315386b183d8f77abf

>>> Removing node fa96dbb2ea63f16f1bc8f8315386b183d8f77abf from cluster 127.0.0.1:8004

[ERR] Node 127.0.0.1:7000 is not empty! Reshard data away and try again.

[root@centos7 cluster]# redis-cli --cluster del-node 127.0.0.1:7000 707d49c11fb1d7ccc7f8b8ea183a8e0261b4166a

>>> Removing node 707d49c11fb1d7ccc7f8b8ea183a8e0261b4166a from cluster 127.0.0.1:7000

>>> Sending CLUSTER FORGET messages to the cluster...

>>> SHUTDOWN the node.

61776:S 21 Jul 2019 03:52:12.508 # User requested shutdown...

61776:S 21 Jul 2019 03:52:12.508 * Calling fsync() on the AOF file.

61776:S 21 Jul 2019 03:52:12.508 * Saving the final RDB snapshot before exiting.

61776:S 21 Jul 2019 03:52:12.509 * DB saved on disk

61776:S 21 Jul 2019 03:52:12.509 * Removing the pid file.

61776:S 21 Jul 2019 03:52:12.510 # Redis is now ready to exit, bye bye...

[1]+  Done                    redis-server ./8004/redis.conf

 

删除主节点

由于删除主节点上分配的槽不为空，所以要删除主节点，首先要通过reshard命令将待删除的节点分配到其他主节点之后才能执行节点的删除动作。

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