On Wed, Jun 21, 2006 at 02:27:39PM +0200, Wolfram Schlich wrote:
Ah, this is the syslog remote logging protocol format? Why is there only PRI inside <>? What about the facility? Is it <FAC.PRI>?
The facility/severity is derived from a single decimal number called the PRI. See http://www.faqs.org/rfcs/rfc3164.html 4.1.1 PRI Part The PRI part MUST have three, four, or five characters and will be bound with angle brackets as the first and last characters. The PRI part starts with a leading "<" ('less-than' character), followed by a number, which is followed by a ">" ('greater-than' character). The code set used in this part MUST be seven-bit ASCII in an eight-bit field as described in RFC 2234 [2]. These are the ASCII codes as defined in "USA Standard Code for Information Interchange" [3]. In this, the "<" character is defined as the Augmented Backus-Naur Form (ABNF) %d60, and the ">" character has ABNF value %d62. The number contained within these angle brackets is known as the Priority value and represents both the Facility and Severity as described below. The Priority value consists of one, two, or three decimal integers (ABNF DIGITS) using values of %d48 (for "0") through %d57 (for "9"). The Facilities and Severities of the messages are numerically coded with decimal values. Some of the operating system daemons and processes have been assigned Facility values. Processes and daemons that have not been explicitly assigned a Facility may use any of the "local use" facilities or they may use the "user-level" Facility. Those Facilities that have been designated are shown in the following table along with their numerical code values. Numerical Facility Code 0 kernel messages 1 user-level messages 2 mail system 3 system daemons 4 security/authorization messages (note 1) 5 messages generated internally by syslogd 6 line printer subsystem 7 network news subsystem 8 UUCP subsystem 9 clock daemon (note 2) 10 security/authorization messages (note 1) 11 FTP daemon 12 NTP subsystem 13 log audit (note 1) 14 log alert (note 1) 15 clock daemon (note 2) 16 local use 0 (local0) 17 local use 1 (local1) 18 local use 2 (local2) 19 local use 3 (local3) 20 local use 4 (local4) 21 local use 5 (local5) 22 local use 6 (local6) 23 local use 7 (local7) Table 1. syslog Message Facilities Note 1 - Various operating systems have been found to utilize Facilities 4, 10, 13 and 14 for security/authorization, audit, and alert messages which seem to be similar. Note 2 - Various operating systems have been found to utilize both Facilities 9 and 15 for clock (cron/at) messages. Each message Priority also has a decimal Severity level indicator. These are described in the following table along with their numerical values. Numerical Severity Code 0 Emergency: system is unusable 1 Alert: action must be taken immediately 2 Critical: critical conditions 3 Error: error conditions 4 Warning: warning conditions 5 Notice: normal but significant condition 6 Informational: informational messages 7 Debug: debug-level messages Table 2. syslog Message Severities The Priority value is calculated by first multiplying the Facility number by 8 and then adding the numerical value of the Severity. For example, a kernel message (Facility=0) with a Severity of Emergency (Severity=0) would have a Priority value of 0. Also, a "local use 4" message (Facility=20) with a Severity of Notice (Severity=5) would have a Priority value of 165. In the PRI part of a syslog message, these values would be placed between the angle brackets as <0> and <165> respectively. The only time a value of "0" will follow the "<" is for the Priority value of "0". Otherwise, leading "0"s MUST NOT be used. -- Nate "They spell it Vinci and pronounce it Vinchy; foreigners always spell better than they pronounce." - Innocents Abroad - Samuel Clemens