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What are MongoDB logs?
As part of normal operation, MongoDB maintains a running log of events, including entries such as incoming connections, commands run, and issues encountered. Generally, log messages are useful for diagnosing issues, monitoring your deployment, and tuning performance.
Where are MongoDB logs stored?
/var/log/mongodb/
MongoDB logs can be found in the MongoDB log files at /var/log/mongodb/mongodb. log. If you can’t find the log files from this location, you can check the mongodb.
Can MongoDB handle transactions?
For situations that require atomicity of reads and writes to multiple documents (in a single or multiple collections), MongoDB supports multi-document transactions. With distributed transactions, transactions can be used across multiple operations, collections, databases, documents, and shards.
How are log messages written in MongoDB 4.4?
Starting in MongoDB 4.4, mongod / mongos instances output all log messages in structured JSON format. Log entries are written as a series of key-value pairs, where each key indicates a log message field type, such as “severity”, and each corresponding value records the associated logging information for that field type, such as “informational”.
What does the severity field mean in MongoDB?
If logging to syslog, the syslog daemon generates timestamps when it logs a message, not when MongoDB issues the message. This can lead to misleading timestamps for log entries, especially when the system is under heavy load. The severity field type indicates the severity level associated with the logged event.
Why is ctime not supported in MongoDB 4.4?
Starting in MongoDB 4.4, the ctime timestamp format is no longer supported. If logging to syslog, the syslog daemon generates timestamps when it logs a message, not when MongoDB issues the message. This can lead to misleading timestamps for log entries, especially when the system is under heavy load.
How are attributes referenced in a MongoDB message?
Attribute values may be referenced by their key name in the message body, depending on the message. Like message, attributes are escaped as needed according to the JSON specification. Tags – (optional) Array of strings representing any tags applicable to the log statement, for example: [“startupWarnings\\.