v1.72

Archive

The Archive backend allows read only access to the content of archive files on cloud storage without downloading them completely.

The archive files are recognised by their extension.

Archive	Extension
Zip	.zip
Squashfs	.sqfs

The supported archive file types are cloud friendly - a single file can be found and downloaded without downloading the whole archive.

Configuration

This backend is best used without configuration.

Use it by putting the string :archive: in front of another remote, say remote:dir to make :archive:remote:dir.

Any archives in remote:dir will become directories and any files may be read out of them individually.

For example

$ rclone lsf s3:rclone/dir
100files.sqfs
100files.zip

Note that 100files.zip and 100files.sqfs are now directories:

$ rclone lsf :archive:s3:rclone/dir
100files.sqfs/
100files.zip/

Which we can look inside:

$ rclone lsf :archive:s3:rclone/dir/100files.zip/
cofofiy5jun
gigi
hevupaz5z
kacak/
kozemof/
lamapaq4
qejahen
quhenen2rey
soboves8
vibat/
wose
xade
zilupot

Files not in an archive can be read and written as normal. Files in an archive can only be read.

The archive backend can also be used in a configuration file. Use the remote variable to point to the destination of the archive.

[remote]
type = archive
remote = s3:rclone/dir/100files.zip

Gives

$ rclone lsf remote:
cofofiy5jun
gigi
hevupaz5z
kacak/
...

Modification times

Modification times are preserved with an accuracy depending on the archive type.

$ rclone lsl --max-depth 1 :archive:s3:rclone/dir/100files.zip
       12 2025-10-27 14:39:20.000000000 cofofiy5jun
       81 2025-10-27 14:39:20.000000000 gigi
       58 2025-10-27 14:39:20.000000000 hevupaz5z
        6 2025-10-27 14:39:20.000000000 lamapaq4
       43 2025-10-27 14:39:20.000000000 qejahen
       66 2025-10-27 14:39:20.000000000 quhenen2rey
       95 2025-10-27 14:39:20.000000000 soboves8
       71 2025-10-27 14:39:20.000000000 wose
       76 2025-10-27 14:39:20.000000000 xade
       15 2025-10-27 14:39:20.000000000 zilupot

For zip and squashfs files this is 1s.

Hashes

Which hash is supported depends on the archive type. Zip files use CRC32, Squashfs don't support any hashes. For example:

$ rclone hashsum crc32 :archive:s3:rclone/dir/100files.zip/
b2288554  cofofiy5jun
a87e62b6  wose
f90f630b  xade
c7d0ef29  gigi
f1c64740  soboves8
cb7b4a5d  quhenen2rey
5115242b  kozemof/fonaxo
afeabd9a  qejahen
71202402  kozemof/fijubey5di
bd99e512  kozemof/napux
...

Hashes will be checked when the file is read from the archive and used as part of syncing if possible.

$ rclone copy -vv :archive:s3:rclone/dir/100files.zip /tmp/100files
...
2025/10/27 14:56:44 DEBUG : kacak/turovat5c/yuyuquk: crc32 = abd05cc8 OK
2025/10/27 14:56:44 DEBUG : kacak/turovat5c/yuyuquk.aeb661dc.partial: renamed to: kacak/turovat5c/yuyuquk
2025/10/27 14:56:44 INFO  : kacak/turovat5c/yuyuquk: Copied (new)
...

Zip

The Zip file format is a widely used archive format that bundles one or more files and folders into a single file, primarily for easier storage or transmission. It typically uses compression (most commonly the DEFLATE algorithm) to reduce the overall size of the archived content. Zip files are supported natively by most modern operating systems.

Rclone does not support the following advanced features of Zip files:

• Splitting large archives into smaller parts
• Password protection
• Zstd compression

Squashfs

Squashfs is a compressed, read-only file system format primarily used in Linux-based systems. It's designed to compress entire file systems (including files, directories, and metadata) into a single archive file, which can then be mounted and read directly, appearing as a normal directory structure. Because it's read-only and highly compressed, Squashfs is ideal for live CDs/USBs, embedded devices with limited storage, and software package distribution, as it saves space and ensures the integrity of the original files.

Rclone supports the following squashfs compression formats:

• Gzip
• Lzma
• Xz
• Zstd

These are not yet working:

• Lzo - Not yet supported
• Lz4 - Broken with "error decompressing: lz4: bad magic number"

Rclone works fastest with large squashfs block sizes. For example:

mksquashfs 100files 100files.sqfs -comp zstd -b 1M

Limitations

Files in archive are read only. It isn't possible to create archives yet.

Only .zip and .sqfs archives are supported as these are the only common archiving formats which make it easy to read directory listings from the archive without downloading the whole archive.

Internally the archive backend uses the VFS to access files. It isn't possible to configure the internal VFS yet which might be useful.

Archive Formats

Here's a table rating common archive formats on their Cloud Optimization which is based on their ability to access a single file without reading the entire archive.

This capability depends on whether the format has a central index (or "table of contents") that a program can read first to find the exact location of a specific file.

Format	Extensions	Cloud Optimized	Explanation
ZIP	.zip	Excellent	Zip files have an index (the "central directory") stored at the end of the file. A program can seek to the end, read the index to find a file's location and size, and then seek directly to that file's data to extract it.
SquashFS	.squashfs, .sqfs, .sfs	Excellent	This is a compressed read-only filesystem image, not just an archive. It is specifically designed for random access. It uses metadata and index tables to allow the system to find and decompress individual files or data blocks on demand.
ISO Image	.iso	Excellent	Like SquashFS, this is a filesystem image (for optical media). It contains a filesystem (like ISO 9660 or UDF) with a table of contents at a known location, allowing for direct access to any file without reading the whole disk.
RAR	.rar	Good	RAR supports "non-solid" and "solid" modes. In the common non-solid mode, files are compressed separately, and an index allows for easy single-file extraction (like ZIP). In "solid" mode, this rating would be "Very Poor."
7z	.7z	Poor	By default, 7z uses "solid" archives to maximize compression. This compresses files as one continuous stream. To extract a file from the middle, all preceding files must be decompressed first. (If explicitly created as "non-solid," its rating would be "Excellent").
tar	.tar	Poor	"Tape Archive" is a streaming format with no central index. To find a file, you must read the archive from the beginning, checking each file header one by one until you find the one you want. This is slow but doesn't require decompressing data.
Gzipped Tar	.tar.gz, .tgz	Very Poor	This is a tar file (already "Poor") compressed with gzip as a single, non-seekable stream. You cannot seek. To get any file, you must decompress the entire archive from the beginning up to that file.
Bzipped/XZ Tar	.tar.bz2, .tar.xz	Very Poor	This is the same principle as tar.gz. The entire archive is one large compressed block, making random access impossible.

Ideas for improvements

It would be possible to add ISO support fairly easily as the library we use (go-diskfs) supports it. We could also add ext4 and fat32 the same way, however in my experience these are not very common as files so probably not worth it. Go-diskfs can also read partitions which we could potentially take advantage of.

It would be possible to add write support, but this would only be for creating new archives, not for updating existing archives.

Standard options

Here are the Standard options specific to archive (Read archives).

--archive-remote

Remote to wrap to read archives from.

Normally should contain a ':' and a path, e.g. "myremote:path/to/dir", "myremote:bucket" or "myremote:".

If this is left empty, then the archive backend will use the root as the remote.

This means that you can use :archive:remote:path and it will be equivalent to setting remote="remote:path".

Properties:

• Config: remote
• Env Var: RCLONE_ARCHIVE_REMOTE
• Type: string
• Required: false

Advanced options

Here are the Advanced options specific to archive (Read archives).

--archive-description

Description of the remote.

Properties:

• Config: description
• Env Var: RCLONE_ARCHIVE_DESCRIPTION
• Type: string
• Required: false

Metadata

Any metadata supported by the underlying remote is read and written.

See the metadata docs for more info.