Description
Split a validated syslog priority integer into facility and severity bit-field values.
Syslog PRI combines a facility code and severity code in one integer: priority = 8 × facility + severity. The integer is framed in angle brackets at the beginning of a syslog message; a PRI token is only one part of that message.1
Split a validated syslog priority integer into facility and severity bit-field values.
When to use this tool
Use this tool to split a validated syslog priority integer into facility and severity bit-field values.
How to use the tool and how it works
- Enter priority using the field definitions below.
- Run the operation. Correct input errors before interpreting an output.
- Read result.facility, result.severity. Use the ordering, boundary rules and absence conditions described below.
Divide priority by eight: floor of the quotient is facility and remainder is severity.2
| Input field | Meaning and units | Accepted input |
|---|---|---|
| priority | Syslog PRI integer 0–191. | A finite safe integer within the operation’s stated bounds. |
| Output field | Interpretation |
|---|---|
| result | Object containing the named fields below. |
| result.facility | Numeric facility code 0–23. |
| result.severity | Numeric severity code 0–7. |
{
"input": {
"priority": 165
},
"output": {
"result": {
"facility": 20,
"severity": 5
}
}
}Limitations and assumptions
- Priority must be 0–191; severity ordering is the syslog convention rather than a caller-defined log-level order.
- Structured log records have id, time, source, level, message and sequence fields. time is a finite caller-defined numeric scale; sequence is an integer from 0 through 1,000,000,000,000. Use the same time units for windows and gap edges.
- Every declared top-level input field is required and unexpected fields are rejected. Ordinary strings are limited to 8,192 UTF-16 code units and lists to 128 entries, with tighter operation-specific bounds where stated. JSON text has bounded nesting and node counts.
- Numeric outputs must be finite and no larger in absolute magnitude than the safe-integer limit; operations returning exact large integers use decimal text. Positions are zero-based and spans end exclusively unless the operation explicitly states a different convention.
Alternative or Complementary methods
Keep original record order and provenance alongside summaries. Sort, partition by source or normalize aliases explicitly before applying a rule that depends on those choices.
References
-
RFC 5424: The Syslog Protocol — RFC Editor
-
Tool behavior and example: Syslog Priority Component Split — tool.io
Similar or alternative tools
- Syslog Priority Component Join
Join validated RFC syslog facility 0–23 and severity 0–7 into the numeric priority, without message serialization.
- Syslog Priority Token Formatter
Parse or format one complete RFC 5424 syslog priority token in the 0–191 range; no full message parsing.