NAME¶

scp — OpenSSH secure file copy

SYNOPSIS¶

DESCRIPTION¶

scp copies files between hosts on a network.

scp uses the SFTP protocol over a ssh(1) connection for data transfer, and uses the same authentication and provides the same security as a login session.

scp will ask for passwords or passphrases if they are needed for authentication.

The source and target may be specified as a local pathname, a remote host with optional path in the form [user@]host:[path], or a URI in the form scp://[user@]host[:port][/path]. Local file names can be made explicit using absolute or relative pathnames to avoid scp treating file names containing ‘:’ as host specifiers.

When copying between two remote hosts, if the URI format is used, a port cannot be specified on the target if the -R option is used.

The options are as follows:

-3

Copies between two remote hosts are transferred through the local host. Without this option the data is copied directly between the two remote hosts. Note that, when using the legacy SCP protocol (via the -O flag), this option selects batch mode for the second host as scp cannot ask for passwords or passphrases for both hosts. This mode is the default.

-4

Forces scp to use IPv4 addresses only.

-6

Forces scp to use IPv6 addresses only.

-A

Allows forwarding of ssh-agent(1) to the remote system. The default is not to forward an authentication agent.

-B

Selects batch mode (prevents asking for passwords or passphrases).

-C

Compression enable. Passes the -C flag to ssh(1) to enable compression.

-c cipher

Selects the cipher to use for encrypting the data transfer. This option is directly passed to ssh(1).

-D sftp_server_path

Connect directly to a local SFTP server program rather than a remote one via ssh(1). This option may be useful in debugging the client and server.

-F ssh_config

Specifies an alternative per-user configuration file for ssh. This option is directly passed to ssh(1).

-i identity_file

Selects the file from which the identity (private key) for public key authentication is read. This option is directly passed to ssh(1).

-J destination

Connect to the target host by first making an scp connection to the jump host described by destination and then establishing a TCP forwarding to the ultimate destination from there. Multiple jump hops may be specified separated by comma characters. This is a shortcut to specify a ProxyJump configuration directive. This option is directly passed to ssh(1).

-l limit

Limits the used bandwidth, specified in Kbit/s.

-O

Use the legacy SCP protocol for file transfers instead of the SFTP protocol. Forcing the use of the SCP protocol may be necessary for servers that do not implement SFTP, for backwards-compatibility for particular filename wildcard patterns and for expanding paths with a ‘~’ prefix for older SFTP servers.

-o ssh_option

Can be used to pass options to ssh in the format used in ssh_config(5). This is useful for specifying options for which there is no separate scp command-line flag. For full details of the options listed below, and their possible values, see ssh_config(5).

AddressFamily

 

BatchMode

 

BindAddress

 

BindInterface

 

CanonicalDomains

 

CanonicalizeFallbackLocal

 

CanonicalizeHostname

 

CanonicalizeMaxDots

 

CanonicalizePermittedCNAMEs

 

CASignatureAlgorithms

 

CertificateFile

 

CheckHostIP

 

Ciphers

 

Compression

 

ConnectionAttempts

 

ConnectTimeout

 

ControlMaster

 

ControlPath

 

ControlPersist

 

GlobalKnownHostsFile

 

GSSAPIAuthentication

 

GSSAPIDelegateCredentials

 

HashKnownHosts

 

Host

 

HostbasedAcceptedAlgorithms

 

HostbasedAuthentication

 

HostKeyAlgorithms

 

HostKeyAlias

 

Hostname

 

IdentitiesOnly

 

IdentityAgent

 

IdentityFile

 

IPQoS

 

KbdInteractiveAuthentication

 

KbdInteractiveDevices

 

KexAlgorithms

 

KnownHostsCommand

 

LogLevel

 

MACs

 

NoHostAuthenticationForLocalhost

 

NumberOfPasswordPrompts

 

PasswordAuthentication

 

PKCS11Provider

 

Port

 

PreferredAuthentications

 

ProxyCommand

 

ProxyJump

 

PubkeyAcceptedAlgorithms

 

PubkeyAuthentication

 

RekeyLimit

 

RequiredRSASize

 

SendEnv

 

ServerAliveInterval

 

ServerAliveCountMax

 

SetEnv

 

StrictHostKeyChecking

 

TCPKeepAlive

 

UpdateHostKeys

 

User

 

UserKnownHostsFile

 

VerifyHostKeyDNS

 

-P port

Specifies the port to connect to on the remote host. Note that this option is written with a capital ‘P’, because -p is already reserved for preserving the times and mode bits of the file.

-p

Preserves modification times, access times, and file mode bits from the source file.

-q

Quiet mode: disables the progress meter as well as warning and diagnostic messages from ssh(1).

-R

Copies between two remote hosts are performed by connecting to the origin host and executing scp there. This requires that scp running on the origin host can authenticate to the destination host without requiring a password.

-r

Recursively copy entire directories. Note that scp follows symbolic links encountered in the tree traversal.

-S program

Name of program to use for the encrypted connection. The program must understand ssh(1) options.

-T

Disable strict filename checking. By default when copying files from a remote host to a local directory scp checks that the received filenames match those requested on the command-line to prevent the remote end from sending unexpected or unwanted files. Because of differences in how various operating systems and shells interpret filename wildcards, these checks may cause wanted files to be rejected. This option disables these checks at the expense of fully trusting that the server will not send unexpected filenames.

-v

Verbose mode. Causes scp and ssh(1) to print debugging messages about their progress. This is helpful in debugging connection, authentication, and configuration problems.

-X sftp_option

Specify an option that controls aspects of SFTP protocol behaviour. The valid options are:

nrequests=value

Controls how many concurrent SFTP read or write requests may be in progress at any point in time during a download or upload. By default 64 requests may be active concurrently.

buffer=value

Controls the maximum buffer size for a single SFTP read/write operation used during download or upload. By default a 32KB buffer is used.

EXIT STATUS¶

The scp utility exits 0 on success, and >0 if an error occurs.

SEE ALSO¶

sftp(1), ssh(1), ssh-add(1), ssh-agent(1), ssh-keygen(1), ssh_config(5), sftp-server(8), sshd(8)

HISTORY¶

scp is based on the rcp program in BSD source code from the Regents of the University of California.

Since OpenSSH 9.0, scp has used the SFTP protocol for transfers by default.

AUTHORS¶

Timo Rinne <tri@iki.fi>
Tatu Ylonen <ylo@cs.hut.fi>

CAVEATS¶

The legacy SCP protocol (selected by the -O flag) requires execution of the remote user's shell to perform glob(3) pattern matching. This requires careful quoting of any characters that have special meaning to the remote shell, such as quote characters.