BSD-syslog or legacy-syslog messages
New to AxoSyslog? AxoSyslog is a binary compatible syslog-ng replacement, from the original creator, developed by the same team.
Same architecture, same config files, same paths. Cloud-native images, fast releases, modern observability (OTel, K8s, Windows), and powerful data processing: read more about the differences between AxoSyslog and syslog-ng.
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This section describes the format of a syslog message, according to the legacy-syslog or BSD-syslog protocol. A syslog message consists of the following parts:
The total message cannot be longer than 1024 bytes.
The following is a sample syslog message
<133>Feb 25 14:09:07 webserver syslogd: restart
The message corresponds to the following format:
<priority>timestamp hostname application: message
The different parts of the message are explained in the following sections.
Note
The AxoSyslog application supports longer messages as well. For details, see the
log-msg-size() option in Global options reference. However, it is not recommended to enable messages larger than the packet size when using UDP destinations.
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