system_error archive command failed with exit code N — 58000

Symptoms

The configured archive_command returned a non-zero exit code, so a WAL segment was not archived. PostgreSQL raises SQLSTATE 58000 (system_error) and retries.

• WAL archiving failed for a segment.
• PostgreSQL retries until it succeeds.
• Unarchived WAL accumulates, risking a full pg_wal.

What the server log shows

LOG:  archive command failed with exit code 1
DETAIL:  The failed archive command was: test ! -f /mnt/arch/000000010000000000000023 && cp pg_wal/000000010000000000000023 /mnt/arch/

Why PostgreSQL raises this — what the manual says

Section 25.3.1 Setting Up WAL Archiving:

“This will cause WAL files to accumulate in pg_wal/ until a working archive_command is re-established.”

Continuous archiving runs archive_command per WAL segment; a zero exit means success. A non-zero exit signals failure, so PostgreSQL keeps the segment and retries, reporting 58000. Persistent failures cause WAL to pile up.

Common causes

• Archive destination full, unreachable, or permission-denied.
• A bug in the archive command (overwrite/exit-code handling).
• Network/mount failure for remote archive storage.

How to fix it

1. Fix the archive destination (space, permissions, connectivity).
2. Test the command manually; ensure it returns 0 only on success and never overwrites.
3. Monitor pg_stat_archiver and pg_wal size to avoid running out of space.

Diagnostic query

SELECT archived_count, failed_count, last_failed_wal, last_failed_time FROM pg_stat_archiver;

Rising failed_count and a recent last_failed_time confirm ongoing archiving failures.

Related & next steps

• SQLSTATE 58000 — System Error (full reference)
• Message: No space left on device
• Glossary: WAL archiving

Reference: PostgreSQL 18 Section 26.3 “Continuous Archiving”.