How do others install a specific previous version of a package using
their system configuration and the `guix system reconfigure config.scm`
command?
I have been able to get a previous version of a package installed in
this case the 2.4.9 version of openvpn.
The command I used was:
`guix package --install-from-file=openvpn-2-4-9.scm`
The contents of `openvpn-2-4-9.scm` is below. It is based on the
openvpn part of `guix/gnu/packages/vpn.scm` at the git commit that
defined version 2.4.9 of openvpn.
```
(use-modules ((guix licenses) #:prefix license:)
(guix packages)
(guix download)
(guix git-download)
(guix build-system cmake)
(guix build-system gnu)
(guix build-system linux-module)
(guix build-system python)
(gnu packages)
(gnu packages admin)
(gnu packages base)
(gnu packages bash)
(gnu packages check)
(gnu packages dns)
(gnu packages autotools)
(gnu packages compression)
(gnu packages gettext)
(gnu packages gnupg)
(gnu packages guile)
(gnu packages libevent)
(gnu packages linux)
(gnu packages nss)
(gnu packages perl)
(gnu packages pkg-config)
(gnu packages python)
(gnu packages python-xyz)
(gnu packages tls)
(gnu packages xml))
(package
(name "openvpn")
(version "2.4.9")
(source (origin
(method url-fetch)
(uri (string-append
"https://swupdate.openvpn.org/community/releases/openvpn-";
version ".tar.xz"))
(sha256
(base32
"1qpbllwlha7cffsd5dlddb8rl22g9rar5zflkz1wrcllhvfkl7v4"))))
(build-system gnu-build-system)
(arguments
'(#:configure-flags '("--enable-iproute2=yes")))
(native-inputs
`(("iproute2" ,iproute)))
(inputs
`(("lz4" ,lz4)
("lzo" ,lzo)
("openssl" ,openssl)
("linux-pam" ,linux-pam)))
(home-page "https://openvpn.net/";)
(synopsis "Virtual private network daemon")
(description
"OpenVPN implements virtual private network (@dfn{VPN}) techniques
for creating secure point-to-point or site-to-site connections in routed or
bridged configurations and remote access facilities. It uses a custom
security protocol that utilizes SSL/TLS for key exchange. It is capable of
traversing network address translators (@dfn{NAT}s) and firewalls.")
(license license:gpl2))
```
