FAQ
Does the collector need root?
No. It only reads the log files you point it at and writes to its spool directory. If your application logs are readable only by their own user, add the service account to that group instead of running as root.
What happens when the backend is unavailable?
Events stay in the spool and the sender retries with exponential backoff. Nothing is dropped until the spool reaches spool.max_size; at that point the oldest acknowledged segments are deleted first, and a warning is logged once per minute.
Can two instances read the same files?
They will both read them, and you will get duplicates. Use one instance per set of files, or split the globs. Offsets are stored in spool.dir/offsets.json, so instances with separate spools never share position.
How are rotated files handled?
The collector re-evaluates the glob every source.rescan and tracks files by inode, so a rename followed by a new file at the same path is picked up without restart. Compression on rotate is fine — the collector only reads the uncompressed part.
Is ordering guaranteed?
Within a single stream, yes: events are appended to the spool in read order and sent in that order. Across streams there is no ordering guarantee, and the backend should not assume one.
How do I upgrade?
Stop the service, replace the binary, start it. The spool format and configuration are stable within a minor version; major versions print a migration note on first start. A running collector never holds the spool exclusively, but batches in flight are retried after restart.
Why is memory growing slowly?
Batch buffers and the sender's in-flight window account for most of it. With the default settings, expect 80–120 MB under sustained load. Growth without bound usually means the backend accepts requests slowly and the spool queue is expanding — check meridian status.
Can I send straight to a file instead of a backend?
Not currently. The collector treats the backend as the only destination on purpose: writing to a local file would make it a log shipper with its own retention problems.