ESXi 8.0 设置的 syslog 消息格式符合 RFC 3164 或 RFC 5424 的要求。
RFC 3164 和 RFC 5424 的传输格式定义采用的是扩展的巴科斯范式 (ABNF)。
RFC 3164 传输消息格式
| 参数 | 值 |
| SYSLOG-MSG | HEADER SP MSG |
| HEADER | PRI TIMESTAMP SP HOSTNAME SP APP-NAME [PROC-IDENTIFIER] ":" |
| PRI | "<" PRIVAL ">" |
| PRIVAL | 1*3DIGIT；范围 0 ..191（MSG PRI；包含设施和严重性值，与 OR 一起使用） |
| APP-NAME | 1*32PRINTUSASCII |
| HOSTNAME | 1*255PRINTUSASCII |
| PROC-IDENTIFIER | "[ "*DIGITS "]"；与 APP-NAME 关联的 PID |
| TIMESTAMP | FULL-DATE "T" UTC-TIME（永不设置 TIME-OFFSET） |
| FULL-DATE | DATE-FULLYEAR "-" DATE-MONTH "-" DATE-MDAY |
| DATE-FULLYEAR | 4DIGIT |
| DATE-MONTH | 2DIGIT ; 01-12 |
| DATE-MDAY | 2DIGIT ; 01-28、01-29、01-30、01-31（基于月/年） |
| UTC-TIME | TIME-HOUR ":" TIME-MINUTE ":" TIME-SECOND [TIME-SECFRAC] "Z" |
| TIME-HOUR | 2DIGIT ; 00-23 |
| TIME-MINUTE | 2DIGIT ; 00-59 |
| TIME-SECOND | 2DIGIT ; 00-59 |
| TIME-SECFRAC | "."1*6DIGIT |
| STRUCTURED-DATA | 1*SD-ELEMENT |
| SD-ELEMENT | "[" SD-ID *(SP SD-PARAM) "]" |
| SD-PARAM | PARAM-NAME "%d34 PARAM-VALUE %d34 |
| SD-ID | SD-NAME |
| PARAM-NAME | SD-NAME |
| PARAM-VALUE | UTF-8-STRING；字符 '"'、'\' 和 ']' 必须转义。 |
| SD-NAME | 1*32PRINTUSASCII；''、SP、']'、%d34 (") 除外 |
| MSG | [STRUCTURED-DATA SP] UTF-8-STRING |
RFC 5424 传输消息格式
| 参数 | 值 |
| SYSLOG-MSG | HEADER SP STRUCTURED-DATA [SP MSG] |
| HEADER | PRI VERSION SP TIMESTAMP SP HOSTNAME SP APP-NAME SP PROCID SP MSGID |
| PRI | "<" PRIVAL ">" |
| PRIVAL | 1*3DIGIT；范围 0 ..191；包含设施和严重性数据 |
| VERSION | NONZERO-DIGIT 0*2DIGIT |
| HOSTNAME | 1*255PRINTUSASCII |
| APP-NAME | 1*48PRINTUSASCII |
| NILVALUE | '-' |
| PROCID | NILVALUE | *DIGITS；PID 与 APP-NAME 关联 |
| MSGID | NILVALUE |
| TIMESTAMP | FULL-DATE "T" UTC-TIME |
| FULL-DATE | DATE-FULLYEAR "-" DATE-MONTH "-" DATE-MDAY |
| DATE-FULLYEAR | 4DIGIT |
| DATE-MONTH | 2DIGIT ; 01-12 |
| DATE-MDAY | 2DIGIT ; 01-28、01-29、01-30、01-31（基于月/年） |
| UTC-TIME | TIME-HOUR ":" TIME-MINUTE ":" TIME-SECOND [TIME-SECFRAC] "Z" |
| TIME-HOUR | 2DIGIT ; 00-23 |
| TIME-MINUTE | 2DIGIT ; 00-59 |
| TIME-SECOND | 2DIGIT ; 00-59 |
| TIME-SECFRAC | "."1*6DIGIT |
| STRUCTURED-DATA | NILVALUE / 1*SD-ELEMENT |
| SD-ELEMENT | "[" SD-ID *(SP SD-PARAM) "]" |
| SD-PARAM | PARAM-NAME " %d34 PARAM-VALUE %d34 |
| SD-ID | SD-NAME |
| PARAM-NAME | SD-NAME |
| PARAM-VALUE | UTF-8-STRING；字符 '"'、'\' 和 ']' 必须转义。 |
| SD-NAME | 1*32PRINTUSASCII ; except '', SP, ']', %d34 (") |
| MSG | MSG-UTF8 |
| MSG-UTF8 | BOM UTF-8-STRING |
| BOM | %xEF.BB.BF |
