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It seems Syslog has a 1KB message limit. Is this hardcoded into the Syslog protocol, or is this a parameter that can be set for each server?
I am hoping the article I read was out of date, so if you have any info please share.
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UDP syslog messages should not exceed 4096 bytes. TCP syslog messages can be increased to 16,384 bytes if users experience truncated events. If you still experience issues after updating the maximum payload size, you can increase the value to 32,000 bytes.
The syslog protocol has been in use for decades as a way to transport messages from network devices to a logging server, typically known as a syslog server. Due to its longevity and popularity, the syslog protocol has support on most major operating systems, including macOS, Linux, and Unix.
Syslog is a standard for sending and receiving notification messages–in a particular format–from various network devices. The messages include time stamps, event messages, severity, host IP addresses, diagnostics and more.
Syslog messages are sent via User Datagram Protocol (UDP), port 514. UDP is what is called a connectionless protocol, so messages aren't acknowledged or guaranteed to arrive. This can be a drawback but also leaves the system simple and easy to manage.
This is correct, as can be seen in the syslog protocol RFC. This, and other deficiencies in the syslog protocol, is the reason why modern syslog daemons such as rsyslog support enhanced protocols with features such as TCP transport, encryption etc. There was also some effort within the IETF to standardize an improved syslog protocol, which resulted in RFC5424, RFC5425, and RFC 5426. Here, the minimum maximum message size is relatively small (depending on the transport layer), however implementations are allowed to support larger messages as well.
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From my reading of the syslog protocol spec (well, draft standard), message packets can't be more than 1KiB, but (using a fragmentation feature) messages can be. RFC 5424, however, says message size depends on transport, but is at least 480 octets.
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