.nh
.TH "desync" "1" "Sep 2026" "desync" ""

.SH NAME
desync-chunk-server - Server for chunks over HTTP(S)


.SH SYNOPSIS
\fBdesync chunk-server [flags]\fP


.SH DESCRIPTION
Starts an HTTP chunk server that can be used as remote store. It supports
reading from multiple local or remote stores as well as a local cache. If
--cert and --key are provided, the server will serve over HTTPS. The -w option
enables writing to this store, but this is only allowed when just one upstream
chunk store is provided. The option --skip-verify-write disables hash validation
of chunks written to this server, avoiding the decompression step needed to
calculate checksums, to improve performance. If -u is used, only uncompressed
chunks are served (and accepted). If the upstream store serves compressed chunks,
everything will have to be decompressed server-side so it's better to also read
from uncompressed upstream stores. With --encryption, chunks are served (and
accepted) encrypted, regardless of how they are stored in the upstream store.
The key is read from the DESYNC_ENCRYPTION_KEY environment variable unless
--encryption-key is used. The environment variable on its own does not enable
encryption, one of the encryption flags is required.

.PP
While --concurrency does not limit the number of clients that can be served
concurrently, it does influence connection pools to remote upstream stores and
needs to be chosen carefully if the server is under high load.

.PP
This command supports the --store-file option which can be used to define the stores
and caches in a JSON file. The config can then be reloaded by sending a SIGHUP without
needing to restart the server. This can be done under load as well.


.SH OPTIONS
\fB--authorization\fP=""
	expected value of the authorization header in requests

.PP
\fB--ca-cert\fP=""
	trust authorities in this file, instead of OS trust store

.PP
\fB-c\fP, \fB--cache\fP=""
	store to be used as cache

.PP
\fB-r\fP, \fB--cache-repair\fP[=true]
	replace invalid chunks in the cache from source

.PP
\fB--cert\fP=""
	cert file in PEM format, requires --key

.PP
\fB--client-ca\fP=""
	acceptable client certificate or CA

.PP
\fB--client-cert\fP=""
	path to client certificate for TLS authentication

.PP
\fB--client-key\fP=""
	path to client key for TLS authentication

.PP
\fB-n\fP, \fB--concurrency\fP=10
	number of concurrent goroutines

.PP
\fB--encryption\fP[=false]
	serve chunks encrypted, expects the key in $DESYNC_ENCRYPTION_KEY unless --encryption-key is given

.PP
\fB--encryption-algorithm\fP=""
	encryption algorithm, xchacha20-poly1305 (default) or aes-256-gcm, implies --encryption

.PP
\fB--encryption-key\fP=""
	serve chunks encrypted with this hex-encoded 256-bit key, implies --encryption

.PP
\fB-e\fP, \fB--error-retry\fP=3
	number of times to retry in case of network error

.PP
\fB-b\fP, \fB--error-retry-base-interval\fP=500ms
	initial retry delay, increases linearly with each subsequent attempt

.PP
\fB-h\fP, \fB--help\fP[=false]
	help for chunk-server

.PP
\fB--key\fP=""
	key file in PEM format, requires --cert

.PP
\fB-l\fP, \fB--listen\fP=[:http]
	listen address(es), can be repeated

.PP
\fB--log\fP=""
	request log file or - for STDOUT

.PP
\fB--mutual-tls\fP[=false]
	require valid client certificate

.PP
\fB--skip-verify-read\fP[=true]
	don't verify chunk data read from upstream stores (faster)

.PP
\fB--skip-verify-write\fP[=true]
	don't verify chunk data written to this server (faster)

.PP
\fB-s\fP, \fB--store\fP=[]
	upstream source store(s)

.PP
\fB--store-file\fP=""
	read store arguments from a file, supports reload on SIGHUP

.PP
\fB-t\fP, \fB--trust-insecure\fP[=false]
	trust invalid certificates

.PP
\fB-u\fP, \fB--uncompressed\fP[=false]
	serve uncompressed chunks

.PP
\fB-w\fP, \fB--writable\fP[=false]
	support writing


.SH OPTIONS INHERITED FROM PARENT COMMANDS
\fB--config\fP=""
	config file (default $HOME/.config/desync/config.json)

.PP
\fB--digest\fP="sha512-256"
	digest algorithm, sha512-256 or sha256

.PP
\fB--verbose\fP[=false]
	verbose mode


.SH EXAMPLE
.EX
  desync chunk-server -s sftp://192.168.1.1/store -c /path/to/cache -l :8080
  desync chunk-server -s /path/to/store -w -l :8080
  desync chunk-server -s /path/to/store --cert cert.pem --key key.pem -l :8443
.EE


.SH SEE ALSO
\fBdesync(1)\fP


.SH HISTORY
5-Sep-2026 Auto generated by spf13/cobra