• Using the SCP command

    SCP aka secure copy or ssh copy is just about the easiest way to quickly transfer files and folders on X based systems without the need to setup FTP servers and accounts. The scp command we use most often just for single files is:

    scp -P port file1 user@server2:~/

    This will simply copy file1 to the home directory of the user on server2. Since we use a non standard port, the -P is very important.

    Sometimes we want to dump a whole folder with subfolders using scp. This command will scp the folder and subfolders to the home folder of user at server2:




    scp -r -P port folder1/ user@server2:~/

    If you use a ssh_key to identify yourself, you can use the -i switch to point to your key:

    scp -r -i ssh_key.file -P port folder/ server2:~/ 

    This will copy the folder and subfolders to the home directory of the user identified by the ssh_key.

    If you want to learn more about scp – just type: man scp

    The contents of this manual are pasted below to easily reference.
    NAME
    scp — secure copy (remote file copy program)

    SYNOPSIS
    scp [-1246BCEpqrv] [-c cipher] [-F ssh_config] [-i identity_file]
    [-l limit] [-o ssh_option] [-P port] [-S program]
    [[user@]host1:]file1 … [[user@]host2:]file2

    DESCRIPTION
    scp copies files between hosts on a network.  It uses ssh(1) for data transfer, and uses the same authentication and provides the same security as ssh(1).  Unlike rcp(1), scp will ask for passwords or passphrases if they are needed for authentication.

    File names may contain a user and host specification to indicate that the file is to be copied to/from that host.
    Local file names can be made explicit using absolute or relative pathnames to avoid scp treating file
    names containing `:’ as host specifiers.  Copies between two remote hosts are also permitted.

    The options are as follows:

    -1   Forces scp to use protocol 1.

    -2   Forces scp to use protocol 2.

    -4   Forces scp to use IPv4 addresses only.

    -6   Forces scp to use IPv6 addresses only.

    -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).

    -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).

    -l     limit
    Limits the used bandwidth, specified in Kbit/s.

    -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
    ChallengeResponseAuthentication
    CheckHostIP
    Cipher
    Ciphers
    Compression
    CompressionLevel
    ConnectionAttempts
    ConnectTimeout
    ControlMaster
    ControlPath
    GlobalKnownHostsFile
    GSSAPIAuthentication
    GSSAPIDelegateCredentials
    HashKnownHosts
    Host
    HostbasedAuthentication
    HostKeyAlgorithms
    HostKeyAlias
    HostName
    IdentityFile
    IdentitiesOnly
    KbdInteractiveDevices
    LogLevel
    MACs
    NoHostAuthenticationForLocalhost
    NumberOfPasswordPrompts
    PasswordAuthentication
    Port
    PreferredAuthentications
    Protocol
    ProxyCommand
    PubkeyAuthentication
    RekeyLimit
    RhostsRSAAuthentication
    RSAAuthentication
    SendEnv
    ServerAliveInterval
    ServerAliveCountMax
    SmartcardDevice
    StrictHostKeyChecking
    TCPKeepAlive
    UsePrivilegedPort
    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 modes of the file in rcp(1).

    -p    Preserves modification times, access times, and modes from the original file.

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

    -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.

    -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.

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

    SCP on Mac has an extra option:

    -E    Preserves extended attributes, resource forks, and ACLs.
    Requires both ends to be running Mac OS X 10.4 or later.



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