> For the complete documentation index, see [llms.txt](https://docs.postgresql.tw/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.postgresql.tw/internals/backup-manifest-format/backup-manifest-wal-ranges.md).

# 70.3. Backup Manifest WAL Range Object \#

The object which describes a WAL range always has three keys:

`Timeline` : The timeline for this range of WAL records, as an integer.

`Start-LSN` : The LSN at which replay must begin on the indicated timeline in order to make use of this backup. The LSN is stored in the format normally used by PostgreSQL; that is, it is a string consisting of two strings of hexadecimal characters, each with a length of between 1 and 8, separated by a slash.

`End-LSN` : The earliest LSN at which replay on the indicated timeline may end when making use of this backup. This is stored in the same format as `Start-LSN`.

Ordinarily, there will be only a single WAL range. However, if a backup is taken from a standby which switches timelines during the backup due to an upstream promotion, it is possible for multiple ranges to be present, each with a different timeline. There will never be multiple WAL ranges present for the same timeline.

***

原文：[PostgreSQL 18.6 Documentation](https://www.postgresql.org/docs/18/backup-manifest-wal-ranges.html)（英文原文，待翻譯）


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