From 21531add3205e400707c8fbfd841845f9a71863a Mon Sep 17 00:00:00 2001 From: Ludovic Courtès Date: Sun, 2 Mar 2014 22:39:48 +0100 Subject: offload: Use Guile-SSH instead of GNU lsh. * guix/scripts/offload.scm ()[ssh-options]: Remove. [host-key, host-key-type]: New fields. (%lsh-command, %lshg-command, user-lsh-private-key): Remove. (user-openssh-private-key, private-key-from-file*): New procedures. (host-key->type+key, open-ssh-session): New procedures. (remote-pipe): Remove 'mode' parameter. Rewrite in terms of 'open-ssh-session' etc. Update users. (send-files)[missing-files]: Rewrite using the bidirectional channel port. Remove call to 'call-with-compressed-output-port'. (retrieve-files): Remove call to 'call-with-decompressed-port'. (machine-load): Remove exit status logic. * doc/guix.texi (Requirements): Mention Guile-SSH. (Daemon Offload Setup): Document 'host-key' and 'private-key'. Show the default value on each @item line. * m4/guix.m4 (GUIX_CHECK_GUILE_SSH): New macro. * config-daemon.ac: Use 'GUIX_CHECK_GUILE_SSH'. Set 'HAVE_DAEMON_OFFLOAD_HOOK' as a function of that. --- doc/guix.texi | 69 ++++++++++++++++++++++++++++++++++++++++++----------------- 1 file changed, 49 insertions(+), 20 deletions(-) (limited to 'doc') diff --git a/doc/guix.texi b/doc/guix.texi index ebb138e15d..f1cb007aa9 100644 --- a/doc/guix.texi +++ b/doc/guix.texi @@ -566,6 +566,12 @@ allow you to use the @command{guix import pypi} command (@pxref{Invoking guix import}). It is of interest primarily for developers and not for casual users. +@item +@c Note: We need at least 0.10.2 for 'channel-send-eof'. +Support for build offloading (@pxref{Daemon Offload Setup}) depends on +@uref{https://github.com/artyom-poptsov/guile-ssh, Guile-SSH}, +version 0.10.2 or later. + @item When @url{http://zlib.net, zlib} is available, @command{guix publish} can compress build byproducts (@pxref{Invoking guix publish}). @@ -814,9 +820,11 @@ available on the system---making it much harder to view them as @cindex offloading @cindex build hook -When desired, the build daemon can @dfn{offload} -derivation builds to other machines -running Guix, using the @code{offload} @dfn{build hook}. When that +When desired, the build daemon can @dfn{offload} derivation builds to +other machines running Guix, using the @code{offload} @dfn{build +hook}@footnote{This feature is available only when +@uref{https://github.com/artyom-poptsov/guile-ssh, Guile-SSH} is +present.}. When that feature is enabled, a list of user-specified build machines is read from @file{/etc/guix/machines.scm}; every time a build is requested, for instance via @code{guix build}, the daemon attempts to offload it to one @@ -832,16 +840,18 @@ The @file{/etc/guix/machines.scm} file typically looks like this: (list (build-machine (name "eightysix.example.org") (system "x86_64-linux") + (host-key "ssh-ed25519 AAAAC3Nza@dots{}") (user "bob") - (speed 2.)) ; incredibly fast! + (speed 2.)) ;incredibly fast! (build-machine (name "meeps.example.org") (system "mips64el-linux") + (host-key "ssh-rsa AAAAB3Nza@dots{}") (user "alice") (private-key (string-append (getenv "HOME") - "/.lsh/identity-for-guix")))) + "/.ssh/identity-for-guix")))) @end example @noindent @@ -875,31 +885,50 @@ The user account to use when connecting to the remote machine over SSH. Note that the SSH key pair must @emph{not} be passphrase-protected, to allow non-interactive logins. +@item host-key +This must be the machine's SSH @dfn{public host key} in OpenSSH format. +This is used to authenticate the machine when we connect to it. It is a +long string that looks like this: + +@example +ssh-ed25519 AAAAC3NzaC@dots{}mde+UhL hint@@example.org +@end example + +If the machine is running the OpenSSH daemon, @command{sshd}, the host +key can be found in a file such as +@file{/etc/ssh/ssh_host_ed25519_key.pub}. + +If the machine is running the SSH daemon of GNU@tie{}lsh, +@command{lshd}, the host key is in @file{/etc/lsh/host-key.pub} or a +similar file. It can be converted to the OpenSSH format using +@command{lsh-export-key} (@pxref{Converting keys,,, lsh, LSH Manual}): + +@example +$ lsh-export-key --openssh < /etc/lsh/host-key.pub +ssh-rsa AAAAB3NzaC1yc2EAAAAEOp8FoQAAAQEAs1eB46LV@dots{} +@end example + @end table A number of optional fields may be specified: -@table @code - -@item port -Port number of SSH server on the machine (default: 22). +@table @asis -@item private-key -The SSH private key file to use when connecting to the machine. +@item @code{port} (default: @code{22}) +Port number of SSH server on the machine. -Currently offloading uses GNU@tie{}lsh as its SSH client -(@pxref{Invoking lsh,,, GNU lsh Manual}). Thus, the key file here must -be an lsh key file. This may change in the future, though. +@item @code{private-key} (default: @file{~/.ssh/id_rsa}) +The SSH private key file to use when connecting to the machine, in +OpenSSH format. -@item parallel-builds -The number of builds that may run in parallel on the machine (1 by -default.) +@item @code{parallel-builds} (default: @code{1}) +The number of builds that may run in parallel on the machine. -@item speed +@item @code{speed} (default: @code{1.0}) A ``relative speed factor''. The offload scheduler will tend to prefer machines with a higher speed factor. -@item features +@item @code{features} (default: @code{'()}) A list of strings denoting specific features supported by the machine. An example is @code{"kvm"} for machines that have the KVM Linux modules and corresponding hardware support. Derivations can request features by @@ -915,7 +944,7 @@ machines, since offloading works by invoking the @code{guix archive} and this is the case by running: @example -lsh build-machine guile -c "'(use-modules (guix config))'" +ssh build-machine guile -c "'(use-modules (guix config))'" @end example There is one last thing to do once @file{machines.scm} is in place. As -- cgit v1.2.3