# Redis plugin
Provides native Zabbix solution for monitoring Redis servers (in-memory data structure store). It can monitor several 
Redis instances simultaneously, remotes or locals to the Zabbix Agent. Both TCP and Unix-socket connections are 
supported. The plugin keeps connections in the opened state to reduce network congestion, latency, CPU and 
memory usage. Best for use in conjunction with the official 
[Redis template.](https://git.zabbix.com/projects/ZBX/repos/zabbix/browse/templates/db/redis)
You can extend it or create your template for your specific needs. 

## Requirements
* Zabbix Agent 2
* Go >= 1.13 (required only to build from source)

## Supported versions
* Redis, version 3.0+

## Installation
The plugin is supplied as a part of Zabbix Agent 2, and it does not require any special installation steps. Once 
Zabbix Agent 2 installed, the plugin is ready to work. The only thing you need to do is to make sure a Redis 
instance is available for connection.

## Configuration
The Zabbix Agent's configuration file is used to configure plugins.

**Plugins.Redis.KeepAlive** — Sets a time for waiting before unused connections will be closed.  
*Default value:* 300 sec.  
*Limits:* 60-900

**Plugins.Redis.Timeout** — The maximum time for waiting when a request has to be done.  
*Default value:* equals the global Timeout configuration parameter.  
*Limits:* 1-30

### Configuring connection
A connection can be configured using either keys' parameters or named sessions.     

*Notes*:  
* It is not possible to mix configuration using named sessions and keys' parameters simultaneously.
* You can leave any connection parameter empty, a default hard-coded value will be used in the such case.
* Embedded URI credentials (userinfo) are forbidden and will be ignored. So, you can't pass the credentials by this:   
  
      redis.ping[tcp://user:password@127.0.0.1] — WRONG  
  
  The correct way is:
    
      redis.ping[tcp://127.0.0.1,password]
      
* The only supported network schemas for a URI are "tcp" and "unix".  
Examples of valid URIs:
    - tcp://127.0.0.1:6379
    - tcp://localhost
    - localhost
    - unix:/var/run/redis.sock
    - /var/run/redis.sock
      
#### Using keys' parameters
The common parameters for all keys are: [ConnString][,Password]  
Where ConnString can be either a URI or a session name.   
ConnString will be treated as a URI if no session with the given name is found.  
If you use ConnString as a session name, just skip the rest of the connection parameters.  
 
#### Using named sessions
Named sessions allow you to define specific parameters for each Redis instance. Currently, there are only two supported 
parameters: Uri and Password. It's a bit more secure way to store credentials compared to item keys or macros.  

E.g: suppose you have two Redis instances: "Prod" and "Test". 
You should add the following options to the agent configuration file:   

    Plugins.Redis.Sessions.Prod.Uri=tcp://192.168.1.1:6379  
    Plugins.Redis.Sessions.Prod.Password=<PasswordForProd>  
      
    Plugins.Redis.Sessions.Test.Uri=tcp://192.168.0.1:6379   
    Plugins.Redis.Sessions.Test.Password=<PasswordForTest>  
        
Then you will be able to use these names as the 1st parameter (ConnString) in keys instead of URIs, e.g:

    redis.ping[Prod]
    redis.ping[Test]

*Note*: sessions names are case-sensitive.

## Supported keys
**redis.config[\<commonParams\>[,pattern]]** — Gets a configuration parameters of a Redis instance matching pattern.  
*Params:*  
pattern — Glob-style pattern. The default value is "*".  
*Returns:*
- JSON if a glob-style pattern is specified.
- Single value if a pattern did not contain any wildcard character.

**redis.info[\<commonParams\>[,section]]** — Returns an output of the INFO command serialized to JSON.  
*Params:*  
section — Section of information. The default section name is "default".

**redis.ping[\<commonParams\>]** — Tests if a connection is alive or not.  
*Returns:*
- "1" if a connection is alive.
- "0" if a connection is broken (if there is any error presented including AUTH and configuration issues).

**redis.slowlog.count[\<commonParams\>]** — Returns the number of slow log entries since Redis was started.

## Troubleshooting
The plugin uses Zabbix agent's logs. You can increase debugging level of Zabbix Agent if you need more details about 
what is happening.