Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S964974AbWBHP5b (ORCPT ); Wed, 8 Feb 2006 10:57:31 -0500 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S964997AbWBHP5b (ORCPT ); Wed, 8 Feb 2006 10:57:31 -0500 Received: from e2.ny.us.ibm.com ([32.97.182.142]:19381 "EHLO e2.ny.us.ibm.com") by vger.kernel.org with ESMTP id S964974AbWBHP5b (ORCPT ); Wed, 8 Feb 2006 10:57:31 -0500 Message-ID: <43EA14E4.4030806@watson.ibm.com> Date: Wed, 08 Feb 2006 10:57:24 -0500 From: Hubertus Franke User-Agent: Mozilla Thunderbird 1.0.2 (Windows/20050317) X-Accept-Language: en-us, en MIME-Version: 1.0 To: Kirill Korotaev CC: "Serge E. Hallyn" , "Eric W. Biederman" , Sam Vilain , Rik van Riel , Kirill Korotaev , Linus Torvalds , Andrew Morton , linux-kernel@vger.kernel.org, clg@fr.ibm.com, haveblue@us.ibm.com, greg@kroah.com, alan@lxorguk.ukuu.org.uk, arjan@infradead.org, kuznet@ms2.inr.ac.ru, saw@sawoct.com, devel@openvz.org, Dmitry Mishin , Herbert Poetzl Subject: Re: The issues for agreeing on a virtualization/namespaces implementation. References: <43E83E8A.1040704@vilain.net> <43E8D160.4040803@watson.ibm.com> <20060207201908.GJ6931@sergelap.austin.ibm.com> <43E90716.4020208@watson.ibm.com> <43E92EDC.8040603@watson.ibm.com> <43EA02D6.30208@watson.ibm.com> <20060208151726.GA28602@sergelap.austin.ibm.com> <43EA0FDB.9050008@sw.ru> In-Reply-To: <43EA0FDB.9050008@sw.ru> Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2113 Lines: 56 Kirill Korotaev wrote: >>> Eric W. Biederman wrote: >>> So it seems the clone( flags ) is a reasonable approach to create new >>> namespaces. Question is what is the initial state of each namespace? >>> In pidspace we know we should be creating an empty pidmap ! >>> In network, someone suggested creating a loopback device >>> In uts, create "localhost" >>> Are there examples where we rather inherit ? Filesystem ? >> >> Of course filesystem is already implemented, and does inheret a full >> copy. > > > why do we want to use clone()? Just because of its name and flags? > I think it is really strange to fork() to create network context. What > has process creation has to do with it? > > After all these clone()'s are called, some management actions from host > system are still required, to add these IPs/routings/etc. > So? Why mess it up? Why not create a separate clean interface for > container management? > > Kirill > We need a "init" per container, which represents the context of the system represented by the container. If that is the case, then why not create the container such that we specify what namespaces need to be new for a container at the container creation time and initialize them to a well understood state that makes sense (e.g. copy namespace (FS, uts) , new fresh state (pid) ). Then use the standard syscall to modify state (now "virtualized" through the task->xxx_namespace access ). Do you see a need to change the namespace of a container after it has been created. I am not referring to the state of the namespace but truely moving to a completely different namespace after the container has been created. Obviously you seem to have some other usage in mind, beyond what my limited vision can see. Can you share some of those examples, because that would help this discussion along ... Thanks a 10^6. -- Hubertus - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/