Redis publish and subscribe, transactions, backup recovery, monitoring

Redis publish subscribe


##Open subscription channel redisChat on a client
[redis@zabbix Desktop]$  redis-cli -h localhost -p 6379 -a redis
#Subscribe to a given channel or channels for information
localhost:6379> SUBSCRIBE redisChat
Reading messages... (press Ctrl-C to quit)
1) "subscribe"
2) "redisChat"
3) (integer) 1

Publish a message to a channel on another client
[root@zabbix bin]# redis-cli -h localhost -p 6379 -a redis
#Send the message to the specified channel.
localhost:6379> PUBLISH redisChat "Redis is a great caching technique"
(integer) 1
localhost:6379>

At this time, when viewing the subscription client, you can see the following information
1) "message"
2) "redisChat"
3) "Redis is a great caching technique"


Redis transactions

#Mark the start of a transaction block.
localhost:6379> MULTI
OK
localhost:6379> set name donald
QUEUED
localhost:6379> get name
QUEUED
localhost:6379> sadd user rain jamel
QUEUED
localhost:6379> smembers user
QUEUED
#Execute commands in all transaction blocks
localhost:6379> exec
1) OK
2) "donald"
3) (integer) 2
4) 1) "rain"
   2) "jamel"
localhost:6379>


Redis connection

localhost:6379> auth redis
OK
localhost:6379> ping
PONG
localhost:6379> echo hello
"hello"
#Switch database, the default database is 0, the maximum is databases
# Set the number of databases. The default database is DB 0, you can select
# a different one on a per-connection basis using SELECT <dbid> where
# dbid is a number between 0 and 'databases'-1
databases 16

localhost:6379> select 0
OK
localhost:6379> get name
"donald"
localhost:6379> smembers user
1) "rain"
2) "jamel"
localhost:6379>



Redis server

##Number of server keys
localhost:6379> dbsize
(integer) 3
##Execute an AOF (AppendOnly File) file rewriting operation asynchronously
localhost:6379> BGREWRITEAOF
Background append only file rewriting started
#Asynchronously save the current database data to disk in the background
localhost:6379> BGSAVE
Background saving started
#Get server time
localhost:6379> time
1) "1482283953"
2) "871588"
##Server roles
localhost:6379> role
1) "master"
2) (integer) 0
3) (empty list or set)
##Get various information and statistical values ​​of the Redis server
localhost:6379> info

#server
# Server
redis_version:3.0.5
redis_git_sha1:00000000
redis_git_dirty:0
redis_build_id:2b4372a303619568
redis_mode:standalone
os: Linux 3.10.0-327.22.2.el7.x86_64 x86_64
arch_bits:64
multiplexing_api:epoll
gcc_version:4.8.5
process_id:4839
run_id:887dbc822c9f9d497c05fc11cc34a6a822357c18
tcp_port:6379
uptime_in_seconds:1314
uptime_in_days:0
hz:10
lru_clock:5888962
config_file:/usr/local/redis/conf/redis.conf

#client
# Clients
connected_clients:1
client_longest_output_list:0
client_biggest_input_buf:0
blocked_clients:0

#RAM
# Memory
used_memory:815592
used_memory_human:796.48K
used_memory_rss:8212480
used_memory_peak:835392
used_memory_peak_human:815.81K
used_memory_lua:36864
mem_fragmentation_ratio:10.07
mem_allocator:jemalloc-3.6.0

##Persistent state
# Persistence
loading:0
rdb_changes_since_last_save:0
rdb_bgsave_in_progress:0
rdb_last_save_time:1482283929
rdb_last_bgsave_status:ok
rdb_last_bgsave_time_sec:0
rdb_current_bgsave_time_sec:-1
aof_enabled:1
aof_rewrite_in_progress:0
aof_rewrite_scheduled:0
aof_last_rewrite_time_sec:0
aof_current_rewrite_time_sec:-1
aof_last_bgrewrite_status:ok
aof_last_write_status:ok
aof_current_size:172
aof_base_size:172
aof_pending_rewrite:0
aof_buffer_length:0
aof_rewrite_buffer_length:0
aof_pending_bio_fsync:0
aof_delayed_fsync:0
##
# Stats
total_connections_received:3
total_commands_processed:25
instantaneous_ops_per_sec:0
total_net_input_bytes:711
total_net_output_bytes:564
instantaneous_input_kbps:0.00
instantaneous_output_kbps:0.00
rejected_connections:0
sync_full:0
sync_partial_ok:0
sync_partial_err:0
expired_keys:0
evicted_keys:0
keyspace_hits:9
keyspace_misses:0
pubsub_channels:0
pubsub_patterns:0
latest_fork_usec:764
migrate_cached_sockets:0

##cluster
# Replication
role:master
connected_slaves:0
master_repl_offset:0
repl_backlog_active:0
repl_backlog_size:1048576
repl_backlog_first_byte_offset:0
repl_backlog_histlen:0
##CPU
# CPU
used_cpu_sys:2.25
used_cpu_user:0.12
used_cpu_sys_children:0.35
used_cpu_user_children:0.00

# Cluster
cluster_enabled:0

# Keyspace
db0:keys=3,expires=0,avg_ttl=0
localhost:6379>
#Print out the commands received by the Redis server in real time, for debugging
localhost:6379> MONITOR
OK
1482284030.614149 [0 127.0.0.1:46386] "AUTH" "redis"
1482284033.695838 [0 127.0.0.1:46386] "get" "name"
1482284045.407687 [0 127.0.0.1:46386] "set" "name" "rain"
#delete all keys in the current database
localhost:6379> FLUSHDB
OK
localhost:6379> dbsize
(integer) 0
localhost:6379>

Redis data backup and recovery

localhost:6379>
#Create a redis backup file can also use the command BGSAVE, which is executed in the background
localhost:6379> bgsave
Background saving started
Data recovery
If you need to restore data, just move the backup file (dump.rdb) to the redis installation directory and start the service
##Get data directory
localhost:6379> CONFIG GET dir
1) "you"
2) "/redis/data"


Redis Security

##Get the verification password
localhost:6379> CONFIG get requirepass
1) "requirepass"
2) "redis"
localhost:6379>
localhost:6379> auth redis
OK
localhost:6379>
#set password
CONFIG set requirepass "redis


Redis client connection

#Return the list of clients connected to the redis service
localhost:6379> client list
id=2 addr=127.0.0.1:46380 fd=7 name= age=2699 idle=140 flags=O db=0 sub=0 psub=0 multi=-1 qbuf=0 qbuf-free=0 obl=56 oll=0 omem=0 events=rw cmd=monitor
id=5 addr=127.0.0.1:46386 fd=6 name= age=1383 idle=0 flags=N db=0 sub=0 psub=0 multi=-1 qbuf=0 qbuf-free=32768 obl=0 oll=0 omem=0 events=r cmd=client
#Set the name of the current connection
localhost:6379> client setname rain
OK
#Get the service name set by the CLIENT SETNAME command
localhost:6379> client getname
"rain"