On Windows or MacOS you can install the binary package directly from CRAN:
install.packages("ssh")Installation from source requires libssh (which is
not libssh2). On Debian
or Ubuntu use libssh-dev:
sudo apt-get install -y libssh-devOn Fedora we need libssh-devel:
sudo yum install libssh-develOn CentOS / RHEL we install libssh-devel via EPEL:
sudo yum install epel-release
sudo yum install libssh-develOn OS-X use libssh from Homebrew:
brew install libsshFirst create an ssh session by connecting to an SSH server.
session <- ssh_connect("jeroen@dev.opencpu.org")
print(session)<ssh session>
jeroen@dev.opencpu.org:22 (connected)
server: 90:eb:52:6b:ee:fc:de:f1:c0:66:6c:53:82:dd:ce:80:d3:85:1e:d8Once established, a session is closed automatically by the garbage
collector when the object goes out of scope or when R quits. You can
also manually close it using ssh_disconnect() but this is
not strictly needed.
The client attempts to use the following authentication methods (in this order) until one succeeds:
privkey argument in
ssh_connect() if specified~/.ssh/config or any of the
default locations: ~/.ssh/id_ed25519,
~/.ssh/id_ecdsa, ~/.ssh/id_rsa, or
.ssh/id_dsa.To debug authentication set verbosity to at least level 2 or 3:
session <- ssh_connect("jeroen@dev.opencpu.org", verbose = 2)ssh_socket_connect: Nonblocking connection socket: 7
ssh_connect: Socket connecting, now waiting for the callbacks to work
socket_callback_connected: Socket connection callback: 1 (0)
ssh_client_connection_callback: SSH server banner: SSH-2.0-OpenSSH_7.2p2 Ubuntu-4ubuntu2.4
ssh_analyze_banner: Analyzing banner: SSH-2.0-OpenSSH_7.2p2 Ubuntu-4ubuntu2.4
ssh_analyze_banner: We are talking to an OpenSSH client version: 7.2 (70200)
ssh_packet_dh_reply: Received SSH_KEXDH_REPLY
ssh_client_curve25519_reply: SSH_MSG_NEWKEYS sent
ssh_packet_newkeys: Received SSH_MSG_NEWKEYS
ssh_packet_newkeys: Signature verified and valid
ssh_packet_userauth_failure: Access denied. Authentication that can continue: publickey
ssh_packet_userauth_failure: Access denied. Authentication that can continue: publickey
ssh_agent_get_ident_count: Answer type: 12, expected answer: 12
ssh_userauth_publickey_auto: Successfully authenticated using /Users/jeroen/.ssh/id_rsaTools for setting up and debugging your ssh keys are provided via the
credentials
package.
ssh_key_info()$key
[1] "/Users/jeroen/.ssh/id_ed25519"
$pubkey
[1] "ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAILGN+5tybmwKhcxvnwPSKlrp39Ni1gMD0UhV4gCxHg/x"Run a command or script on the host and block while it runs. By default stdout and stderr are steamed directly back to the client. This function returns the exit status of the remote command (hence it does not automatically error for an unsuccessful exit status).
out <- ssh_exec_wait(session, command = 'whoami')jeroenprint(out)[1] 0You can also run a script that consists of multiple commands.
ssh_exec_wait(session, command = c(
'curl -O https://cran.r-project.org/src/contrib/Archive/jsonlite/jsonlite_1.4.tar.gz',
'R CMD check jsonlite_1.4.tar.gz',
'rm -f jsonlite_1.4.tar.gz'
)) % Total % Received % Xferd Average Speed Time Time Time Current
Dload Upload Total Spent Left Speed
100 1071k 100 1071k 0 0 654k 0 0:00:01 0:00:01 --:--:-- 654k
* using log directory '/home/jeroen/jsonlite.Rcheck'
* using R version 3.4.3 (2017-11-30)
* using platform: x86_64-pc-linux-gnu (64-bit)
* using session charset: ASCII
* checking for file 'jsonlite/DESCRIPTION' ... OK
* this is package 'jsonlite' version '1.4'
* checking package namespace information ... OK
* checking package dependencies ...
...The ssh_exec_internal() is a convenient wrapper for
ssh_exec_wait() which buffers the output steams and returns
them as a raw vector. Also it raises an error by default when the remote
command was not successful.
out <- ssh_exec_internal(session, "R -e 'rnorm(10)'")
print(out$status)[1] 0cat(rawToChar(out$stdout))
R version 4.1.2 (2021-11-01) -- "Bird Hippie"
Copyright (C) 2021 The R Foundation for Statistical Computing
Platform: x86_64-pc-linux-gnu (64-bit)
R is free software and comes with ABSOLUTELY NO WARRANTY.
You are welcome to redistribute it under certain conditions.
Type 'license()' or 'licence()' for distribution details.
Natural language support but running in an English locale
R is a collaborative project with many contributors.
Type 'contributors()' for more information and
'citation()' on how to cite R or R packages in publications.
Type 'demo()' for some demos, 'help()' for on-line help, or
'help.start()' for an HTML browser interface to help.
Type 'q()' to quit R.
> rnorm(10)
[1] -0.3837970 0.9754719 0.9999716 -0.2634097 0.1845797 -0.5664418
[7] 0.6975547 -0.2063897 -0.7263869 2.3826802
>
> This function is very useful if you are running a remote command and want to use it’s output as if you had executed it locally.
Note that the exec functions are non interactive so they cannot
prompt for a sudo password. A trick is to use -S which
reads the password from stdin:
command <- 'echo "mypassword!" | sudo -s -S apt-get update -y'
out <- ssh_exec_wait(session, command)Be very careful with hardcoding passwords!
Upload and download files via SCP. Directories are automatically
traversed as in scp -r.
# Upload a file to the server
file_path <- R.home("COPYING")
scp_upload(session, file_path)# Download the file back and verify it is the same
scp_download(session, "COPYING", to = tempdir())
tools::md5sum(file_path)
tools::md5sum(file.path(tempdir(), "COPYING"))Opens a port on your machine and tunnel all traffic to a custom target host via the SSH server.
ssh_tunnel(session, port = 5555, target = "ds043942.mongolab.com:43942")This function blocks while the tunnel is active. Use the tunnel by
connecting to localhost:5555 from a separate process. The
tunnel can only be used once and will automatically be closed when the
client disconnects.
When you are done with the session you should disconnect:
ssh_disconnect(session)If you forgot to disconnect, the garbage collector will do so for you (with a warning).