# Telegraf Plugin: Redis

### Configuration:

```
# Read Redis's basic status information
[[inputs.redis]]
  ## specify servers via a url matching:
  ##  [protocol://][:password]@address[:port]
  ##  e.g.
  ##    tcp://localhost:6379
  ##    tcp://:password@192.168.99.100
  ##
  ## If no servers are specified, then localhost is used as the host.
  ## If no port is specified, 6379 is used
  servers = ["tcp://localhost:6379"]

  ## specify server password
  # password = "s#cr@t%"

  ## Optional TLS Config
  # tls_ca = "/etc/telegraf/ca.pem"
  # tls_cert = "/etc/telegraf/cert.pem"
  # tls_key = "/etc/telegraf/key.pem"
  ## Use TLS but skip chain & host verification
  # insecure_skip_verify = true
```

### Measurements & Fields:

The plugin gathers the results of the [INFO](https://redis.io/commands/info) redis command.
There are two separate measurements: _redis_ and _redis\_keyspace_, the latter is used for gathering database related statistics.

Additionally the plugin also calculates the hit/miss ratio (keyspace\_hitrate) and the elapsed time since the last rdb save (rdb\_last\_save\_time\_elapsed).

- redis
    - keyspace_hitrate(float, number)
    - rdb_last_save_time_elapsed(int, seconds)

    **Server**
    - uptime(int, seconds)
    - lru_clock(int, number)
    - redis_version(string)

    **Clients**
    - clients(int, number)
    - client_longest_output_list(int, number)
    - client_biggest_input_buf(int, number)
    - blocked_clients(int, number)

    **Memory**
    - used_memory(int, bytes)
    - used_memory_rss(int, bytes)
    - used_memory_peak(int, bytes)
    - total_system_memory(int, bytes)
    - used_memory_lua(int, bytes)
    - maxmemory(int, bytes)
    - maxmemory_policy(string)
    - mem_fragmentation_ratio(float, number)

    **Persistance**
    - loading(int,flag)
    - rdb_changes_since_last_save(int, number)
    - rdb_bgsave_in_progress(int, flag)
    - rdb_last_save_time(int, seconds)
    - rdb_last_bgsave_status(string)
    - rdb_last_bgsave_time_sec(int, seconds)
    - rdb_current_bgsave_time_sec(int, seconds)
    - aof_enabled(int, flag)
    - aof_rewrite_in_progress(int, flag)
    - aof_rewrite_scheduled(int, flag)
    - aof_last_rewrite_time_sec(int, seconds)
    - aof_current_rewrite_time_sec(int, seconds)
    - aof_last_bgrewrite_status(string)
    - aof_last_write_status(string)

    **Stats**
    - total_connections_received(int, number)
    - total_commands_processed(int, number)
    - instantaneous_ops_per_sec(int, number)
    - total_net_input_bytes(int, bytes)
    - total_net_output_bytes(int, bytes)
    - instantaneous_input_kbps(float, KB/sec)
    - instantaneous_output_kbps(float, KB/sec)
    - rejected_connections(int, number)
    - sync_full(int, number)
    - sync_partial_ok(int, number)
    - sync_partial_err(int, number)
    - expired_keys(int, number)
    - evicted_keys(int, number)
    - keyspace_hits(int, number)
    - keyspace_misses(int, number)
    - pubsub_channels(int, number)
    - pubsub_patterns(int, number)
    - latest_fork_usec(int, microseconds)
    - migrate_cached_sockets(int, number)

    **Replication**
    - connected_slaves(int, number)
    - master_link_down_since_seconds(int, number)
    - master_link_status(string)
    - master_repl_offset(int, number)
    - second_repl_offset(int, number)
    - repl_backlog_active(int, number)
    - repl_backlog_size(int, bytes)
    - repl_backlog_first_byte_offset(int, number)
    - repl_backlog_histlen(int, bytes)

    **CPU**
    - used_cpu_sys(float, number)
    - used_cpu_user(float, number)
    - used_cpu_sys_children(float, number)
    - used_cpu_user_children(float, number)

    **Cluster**
    - cluster_enabled(int, flag)

- redis_keyspace
    - keys(int, number)
    - expires(int, number)
    - avg_ttl(int, number)

- redis_cmdstat
    Every Redis used command will have 3 new fields:
    - calls(int, number)
    - usec(int, mircoseconds)
    - usec_per_call(float, microseconds)

- redis_replication
  - tags:
    - replication_role
    - replica_ip
    - replica_port
    - state (either "online", "wait_bgsave", or "send_bulk")

  - fields:
    - lag(int, number)
    - offset(int, number)

### Tags:

- All measurements have the following tags:
    - port
    - server
    - replication_role

- The redis_keyspace measurement has an additional database tag:
    - database

- The redis_cmdstat measurement has an additional tag:
    - command

### Example Output:

Using this configuration:
```
[[inputs.redis]]
  ## specify servers via a url matching:
  ##  [protocol://][:password]@address[:port]
  ##  e.g.
  ##    tcp://localhost:6379
  ##    tcp://:password@192.168.99.100
  ##
  ## If no servers are specified, then localhost is used as the host.
  ## If no port is specified, 6379 is used
  servers = ["tcp://localhost:6379"]
```

When run with:
```
./telegraf --config telegraf.conf --input-filter redis --test
```

It produces:
```
* Plugin: redis, Collection 1
> redis,server=localhost,port=6379,replication_role=master,host=host keyspace_hitrate=1,clients=2i,blocked_clients=0i,instantaneous_input_kbps=0,sync_full=0i,pubsub_channels=0i,pubsub_patterns=0i,total_net_output_bytes=6659253i,used_memory=842448i,total_system_memory=8351916032i,aof_current_rewrite_time_sec=-1i,rdb_changes_since_last_save=0i,sync_partial_err=0i,latest_fork_usec=508i,instantaneous_output_kbps=0,expired_keys=0i,used_memory_peak=843416i,aof_rewrite_in_progress=0i,aof_last_bgrewrite_status="ok",migrate_cached_sockets=0i,connected_slaves=0i,maxmemory_policy="noeviction",aof_rewrite_scheduled=0i,total_net_input_bytes=3125i,used_memory_rss=9564160i,repl_backlog_histlen=0i,rdb_last_bgsave_status="ok",aof_last_rewrite_time_sec=-1i,keyspace_misses=0i,client_biggest_input_buf=5i,used_cpu_user=1.33,maxmemory=0i,rdb_current_bgsave_time_sec=-1i,total_commands_processed=271i,repl_backlog_size=1048576i,used_cpu_sys=3,uptime=2822i,lru_clock=16706281i,used_memory_lua=37888i,rejected_connections=0i,sync_partial_ok=0i,evicted_keys=0i,rdb_last_save_time_elapsed=1922i,rdb_last_save_time=1493099368i,instantaneous_ops_per_sec=0i,used_cpu_user_children=0,client_longest_output_list=0i,master_repl_offset=0i,repl_backlog_active=0i,keyspace_hits=2i,used_cpu_sys_children=0,cluster_enabled=0i,rdb_last_bgsave_time_sec=0i,aof_last_write_status="ok",total_connections_received=263i,aof_enabled=0i,repl_backlog_first_byte_offset=0i,mem_fragmentation_ratio=11.35,loading=0i,rdb_bgsave_in_progress=0i 1493101290000000000
```

redis_keyspace:
```
> redis_keyspace,database=db1,host=host,server=localhost,port=6379,replication_role=master keys=1i,expires=0i,avg_ttl=0i 1493101350000000000
```

redis_command:
```
> redis_cmdstat,command=publish,host=host,port=6379,replication_role=master,server=localhost calls=68113i,usec=325146i,usec_per_call=4.77 1559227136000000000
```