Imhiredis: Redis input plugin¶
|Author:||Jeremie Jourdin <email@example.com>|
Imhiredis is an input module reading arbitrary entries from Redis. It uses the hiredis library to query Redis instances using 2 modes:
The queue mode uses Redis LISTs to push/pop messages to/from lists. It allows simple and efficient uses of Redis as a queueing system, providing both LIFO and FIFO methods.
This mode should be preferred if the user wants to use Redis as a caching system, with one (or many) Rsyslog instances POP’ing out entries.
This mode was configured to provide optimal performances while not straining Redis, but as imhiredis has to poll the instance some trade-offs had to be made:
- imhiredis POPs entries by batches of 10 to improve performances (this is currently not configurable)
- when no entries are left in the list, the module sleeps for 1 second before checking the list again. This means messages might be delayed by as much as 1 second between a push to the list and a pop by imhiredis (entries will still be POP’ed out as fast as possible while the list is not empty)
The subscribe mode uses Redis PUB/SUB system to listen to messages published to Redis’ channels. It allows performant use of Redis as a message broker.
This mode should be preferred to use Redis as a message broker, with zero, one or many subscribers listening to new messages.
This mode shouldn’t be used if messages are to be reliably processed, as messages published when no Imhiredis is listening will result in the loss of the message.
This module is able to automatically connect to the master instance of a master/replica(s) cluster. Simply providing a valid connection entry point (being the current master or a valid replica), Imhiredis is able to redirect to the master node on startup and when states change between nodes.
Parameter names are case-insensitive
|word||no||if no server provided||none|
|ip||127.0.0.1||if no socketPath provided||none|
The Redis server’s IP to connect to.
The Redis server’s port to use when connecting via IP.
The password to use when connecting to a Redis node, if necessary.
|Assign messages from this input to a specific Rsyslog ruleset.|
Help with configuring/using