compression.maxExpansionRatio

Limits the cumulative decompressed-to-compressed byte ratio accepted for a stream.

This parameter applies to imptcp: Plain TCP Syslog.

Name:

compression.maxExpansionRatio

Scope:

input

Type:

integer

Default:

input=1024

Required?:

no

Introduced:

8.2612.0

Description

compression.maxExpansionRatio limits how much decompressed output imptcp accepts relative to the compressed bytes received on one session when compression.mode selects stream decompression (stream:always, or stream:auto for sessions detected as compressed). The default allows up to 1024 decompressed bytes per compressed byte.

If the ratio is exceeded, imptcp logs the compressed stream as invalid, discards the remaining stream data, and closes the session. This bounds decompression amplification from malformed or unexpectedly dense compressed streams. Set the value to 0 to disable this ratio limit for tightly controlled deployments.

The parameter behaves like the identically named imtcp parameter.

Input usage

input(
    type="imptcp"
    port="514"
    compression.mode="stream:always"
    compression.maxExpansionRatio="2048"
)

YAML usage

modules:
  - load: imptcp
inputs:
  - type: imptcp
    port: "514"
    compression.mode: "stream:always"
    compression.maxExpansionRatio: "2048"

See also

See also Compression.mode, compression.maxDecompressedBytesPerReceive, and imptcp: Plain TCP Syslog.

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