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+.\" SPDX-License-Identifier: CDDL-1.0
+.\"
+.\" CDDL HEADER START
+.\"
+.\" The contents of this file are subject to the terms of the
+.\" Common Development and Distribution License (the "License").
+.\" You may not use this file except in compliance with the License.
+.\"
+.\" You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
+.\" or https://opensource.org/licenses/CDDL-1.0.
+.\" See the License for the specific language governing permissions
+.\" and limitations under the License.
+.\"
+.\" When distributing Covered Code, include this CDDL HEADER in each
+.\" file and include the License file at usr/src/OPENSOLARIS.LICENSE.
+.\" If applicable, add the following below this CDDL HEADER, with the
+.\" fields enclosed by brackets "[]" replaced with your own identifying
+.\" information: Portions Copyright [yyyy] [name of copyright owner]
+.\"
+.\" CDDL HEADER END
+.\"
+.\" Copyright (c) 2025 iXsystems, Inc.
+.\"
+.Dd July 23, 2025
+.Dt ZFS-REWRITE 8
+.Os
+.
+.Sh NAME
+.Nm zfs-rewrite
+.Nd rewrite specified files without modification
+.Sh SYNOPSIS
+.Nm zfs
+.Cm rewrite
+.Oo Fl Prvx Ns Oc
+.Op Fl l Ar length
+.Op Fl o Ar offset
+.Ar file Ns | Ns Ar directory Ns …
+.
+.Sh DESCRIPTION
+Rewrite blocks of specified
+.Ar file
+as is without modification at a new location and possibly with new
+properties, such as checksum, compression, dedup, copies, etc,
+as if they were atomically read and written back.
+.Bl -tag -width "-r"
+.It Fl P
+Perform physical rewrite, preserving logical birth time of blocks.
+By default, rewrite updates logical birth times, making blocks appear
+as modified in snapshots and incremental send streams.
+Physical rewrite preserves logical birth times, avoiding unnecessary
+inclusion in incremental streams.
+Physical rewrite requires the
+.Sy physical_rewrite
+feature to be enabled on the pool.
+.It Fl l Ar length
+Rewrite at most this number of bytes.
+.It Fl o Ar offset
+Start at this offset in bytes.
+.It Fl r
+Recurse into directories.
+.It Fl v
+Print names of all successfully rewritten files.
+.It Fl x
+Don't cross file system mount points when recursing.
+.El
+.Sh NOTES
+Rewrite of cloned blocks and blocks that are part of any snapshots,
+same as some property changes may increase pool space usage.
+Holes that were never written or were previously zero-compressed are
+not rewritten and will remain holes even if compression is disabled.
+.Pp
+If a
+.Fl l
+or
+.Fl o
+value request a rewrite to regions past the end of the file, then those
+regions are silently ignored, and no error is reported.
+.Pp
+By default, rewritten blocks update their logical birth time,
+meaning they will be included in incremental
+.Nm zfs Cm send
+streams as modified data.
+When the
+.Fl P
+flag is used, rewritten blocks preserve their logical birth time, since
+there are no user data changes.
+.
+.Sh SEE ALSO
+.Xr zfsprops 7 ,
+.Xr zpool-features 7