# The collectd Input

The _collectd_ input allows InfluxDB to accept data transmitted in collectd native format. This data is transmitted over UDP.

## Configuration

Each collectd input allows the binding address, target database, and target retention policy to be set. If the database does not exist, it will be created automatically when the input is initialized. If the retention policy is not configured, then the default retention policy for the database is used. However if the retention policy is set, the retention policy must be explicitly created. The input will not automatically create it.

Each collectd input also performs internal batching of the points it receives, as batched writes to the database are more efficient. The default batch size is 1000, pending batch factor is 5, with a batch timeout of 1 second. This means the input will write batches of maximum size 1000, but if a batch has not reached 1000 points within 1 second of the first point being added to a batch, it will emit that batch regardless of size. The pending batch factor controls how many batches can be in memory at once, allowing the input to transmit a batch, while still building other batches.

The path to the collectd types database file may also be set

## Large UDP packets

Please note that UDP packages larger than the standard size of 1452 are dropped at the time of ingestion, so be sure to set `MaxPacketSize` to 1452 in the collectd configuration.
