From mboxrd@z Thu Jan 1 00:00:00 1970 From: Alex Kost Subject: Re: How to roll back a "guix system reconfigure"? Date: Sat, 02 Apr 2016 23:20:10 +0300 Message-ID: <87r3envk3p.fsf@gmail.com> References: <87inzz7r7m.fsf@gmail.com> Mime-Version: 1.0 Content-Type: text/plain Return-path: Received: from eggs.gnu.org ([2001:4830:134:3::10]:58110) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1amS1m-0003bY-QX for help-guix@gnu.org; Sat, 02 Apr 2016 16:20:15 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1amS1j-0001HK-Kz for help-guix@gnu.org; Sat, 02 Apr 2016 16:20:14 -0400 Received: from mail-lb0-x232.google.com ([2a00:1450:4010:c04::232]:35916) by eggs.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1amS1j-0001Gu-Di for help-guix@gnu.org; Sat, 02 Apr 2016 16:20:11 -0400 Received: by mail-lb0-x232.google.com with SMTP id qe11so106425560lbc.3 for ; Sat, 02 Apr 2016 13:20:11 -0700 (PDT) In-Reply-To: <87inzz7r7m.fsf@gmail.com> (Chris Marusich's message of "Sat, 02 Apr 2016 12:20:29 -0700") List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: help-guix-bounces+gcggh-help-guix=m.gmane.org@gnu.org Sender: help-guix-bounces+gcggh-help-guix=m.gmane.org@gnu.org To: Chris Marusich Cc: help-guix@gnu.org Chris Marusich (2016-04-02 22:20 +0300) wrote: > Hi, > > After running a "guix system reconfigure", it is possible to boot to a > previous version of the system by manually selecting it from the GRUB > menu. However, if you want to permanently roll back to a previous > version (e.g., because something broke), it's a nuisance to do this > every time you boot. Of course, assuming guix is still working after > the reconfigure, you could simply do another "guix system reconfigure" > using the previous version of your operating system configuration file, > but it seems like that shouldn't be necessary. > > What is the recommended way to roll back after a "guix system > reconfigure"? Is it sufficient to manually edit the grub.cfg file to > remove all mention of the generations after the one to which you want to > roll back? If you do that, will the gc root(s) associated with the bad > configuration stay around forever? Would it make sense to add a command > like "guix system roll-back" or "guix system switch-generation", similar > to "guix package --roll-back" and "guix package --switch-generation"? Yes, I think these things will be added eventually. It's just that no one has not been interested enough in these features yet to add them. Currently there are 2 ways to perform a system roll-back: 1. Manually: system generations are just symlinks in "/var/guix/profiles" directory, so you can change "/var/guix/profiles/system" link to point to any previous generation. 2. Using Emacs interface (you have to run emacs as root): - M-x guix-system-generations; - Press "c" on a generation you want to make current. -- Alex