From: Robert P. J. D. <rp...@cr...> - 2008-03-04 22:15:17
|
as the next step in my UML recipe for fedora, i want to demonstrate how to set up simple networking. and to keep things simple, i'd prefer to use a pre-built kernel and root filesystem -- actually configuring and building those things will come later. so where can i find those two objects? as i understand it, for me to set up networking, either the kernel or the root filesystem has to have networking capability. for example, consider the recipe here: http://user-mode-linux.sourceforge.net/network.html note how the instructions for the UML guest involve doing a modprobe, which implies that the root filesystem has to have some modules, but the root filesystem that's available at that site doesn't have any modules. ergo, i can't use it for my example -- does that make sense? in short, can someone give me a pointer to a combo of kernel and root fs for which networking is ready to go? all of the examples i've tried so far don't work. rday -- ======================================================================== Robert P. J. Day Linux Consulting, Training and Annoying Kernel Pedantry: Have classroom, will lecture. http://crashcourse.ca Waterloo, Ontario, CANADA ======================================================================== |
From: Antoine M. <an...@na...> - 2008-03-04 23:11:15
|
-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA512 The kernels and filesystems here: http://uml.nagafix.co.uk/ Should all be set to use dhcp network configuration, just start a dhcp server and you should be up and running. Antoine Robert P. J. Day wrote: | as the next step in my UML recipe for fedora, i want to demonstrate | how to set up simple networking. and to keep things simple, i'd | prefer to use a pre-built kernel and root filesystem -- actually | configuring and building those things will come later. | | so where can i find those two objects? as i understand it, for me | to set up networking, either the kernel or the root filesystem has to | have networking capability. for example, consider the recipe here: | | http://user-mode-linux.sourceforge.net/network.html | | note how the instructions for the UML guest involve doing a modprobe, | which implies that the root filesystem has to have some modules, but | the root filesystem that's available at that site doesn't have any | modules. ergo, i can't use it for my example -- does that make sense? | | in short, can someone give me a pointer to a combo of kernel and | root fs for which networking is ready to go? all of the examples i've | tried so far don't work. | | rday | -- | | ======================================================================== | Robert P. J. Day | Linux Consulting, Training and Annoying Kernel Pedantry: | Have classroom, will lecture. | | http://crashcourse.ca Waterloo, Ontario, CANADA | ======================================================================== | | ------------------------------------------------------------------------- | This SF.net email is sponsored by: Microsoft | Defy all challenges. Microsoft(R) Visual Studio 2008. | http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/ | _______________________________________________ | User-mode-linux-user mailing list | Use...@li... | https://lists.sourceforge.net/lists/listinfo/user-mode-linux-user | -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.7 (GNU/Linux) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org iD8DBQFHzdcDGK2zHPGK1rsRCn9YAJ4rOVEbZI2GqxKlWVSM0phTXZXmlACeJPsn ql7JsAyBl2zgZe6wnlepvUo= =M/hl -----END PGP SIGNATURE----- |
From: Robert P. J. D. <rp...@cr...> - 2008-03-04 23:17:54
|
On Tue, 4 Mar 2008, Antoine Martin wrote: > -----BEGIN PGP SIGNED MESSAGE----- > Hash: SHA512 > > The kernels and filesystems here: > http://uml.nagafix.co.uk/ > Should all be set to use dhcp network configuration, just start a dhcp > server and you should be up and running. > > Antoine but for simplicity's sake, i would prefer not to set up a DHCP server just yet -- i would prefer to configure that first example of networking manually and, step by step, work my way up -- that's the whole point of the "recipe" approach. i've already downloaded, from the nagafix site, the following: * Fedora8-x86-root_fs.bz2 * kernel32-2.6.24.3.bz2 and, certainly, i can start basic UML with those. so now, the question is, what is the exact set of steps to do nothing more than network my host and my guest OS, as simply as possible? rday -- ======================================================================== Robert P. J. Day Linux Consulting, Training and Annoying Kernel Pedantry: Have classroom, will lecture. http://crashcourse.ca Waterloo, Ontario, CANADA ======================================================================== |
From: Antoine M. <an...@na...> - 2008-03-05 00:03:17
|
-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA512 Robert P. J. Day wrote: | On Tue, 4 Mar 2008, Antoine Martin wrote: | |> -----BEGIN PGP SIGNED MESSAGE----- |> Hash: SHA512 |> |> The kernels and filesystems here: |> http://uml.nagafix.co.uk/ |> Should all be set to use dhcp network configuration, just start a dhcp |> server and you should be up and running. |> |> Antoine | | but for simplicity's sake, i would prefer not to set up a DHCP server | just yet -- i would prefer to configure that first example of | networking manually and, step by step, work my way up -- that's the | whole point of the "recipe" approach. | | i've already downloaded, from the nagafix site, the following: | | * Fedora8-x86-root_fs.bz2 | * kernel32-2.6.24.3.bz2 | | and, certainly, i can start basic UML with those. so now, the | question is, what is the exact set of steps to do nothing more than | network my host and my guest OS, as simply as possible? Well, the problem is that if you don't want to use dhcp, you either have to edit some config files on the guest or you have to login and bring the network up by hand... IMO, that's more complicated (and less flexible) than just starting a dhcp server instance. Antoine -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.7 (GNU/Linux) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org iD8DBQFHzeM6GK2zHPGK1rsRCtDXAJ4x+Ge0ZCSHeO1KmgtsJgm3NHbe0QCcCArm AIlP5FSZEjNwqEA3ArrGFBQ= =Q9oy -----END PGP SIGNATURE----- |
From: Robert P. J. D. <rp...@cr...> - 2008-03-06 08:46:27
|
On Wed, 5 Mar 2008, Antoine Martin wrote: > Well, the problem is that if you don't want to use dhcp, you either have > to edit some config files on the guest or you have to login and bring > the network up by hand... > IMO, that's more complicated (and less flexible) than just starting a > dhcp server instance. > > Antoine i know what you're talking about here -- at least, let me make sure i do. at the moment, my host system is 192.168.1.2 on the local home network (router/gateway at 192.168.1.1). if i was setting up UML networking *properly*, i'd allocate a new network exclusively for all of my UML guests -- say 10.0.0.0. and i'd set up a DHCP server on my host that would hand out 10.x.x.x addresses to my UML sessions. i'd also have to have the host doing NAT to allow those UML sessions access to the internet, etc, etc. i believe that's what you're describing at the bottom of the page here, yes? http://uml.nagafix.co.uk/ however, if i have just the one UML session and i just want some quick networking, i can do something much faster and uglier, and steal IP addresses from my current physical network so that i'll have the following tuntap connection between my host and guest: host <----------> UML 192.168.1.254 192.168.1.253 then, in the UML session, i can make 192.168.1.254 my default gateway, and i can set up my host to forward IP packets. (all of that requires manually configuring the UML session, including hard-coding the DNS server, which would be 192.168.1.1, my router.) the above hack does work, but it's admittedly, you know, hacky. and it certainly doesn't scale well if i want to start supporting multiple guest UML sessions. so, just to make sure i understand, yes, DHCP would clearly be a cleaner approach, but it *would* involve allocating a new network to my UML sessions -- i wouldn't want to have my local network with an address of 192.168.1.0 and also be giving out DHCP addresses of the same form to my UML sessions, would i? (it's possible to do that, of course, but it would be ugly.) do i understand this even remotely? rday p.s. this *appears* to be what you're doing in your setup at the bottom of that web page again. i note that, when you start a UML session, you assign the host eth0 an address of 192.168.1.254, which suggests your local (physical) network is 192.168.1.0 (which is pretty standard). but your DHCP server is handing out addresses of the form 192.168.0.x, so that seems to agree with what i wrote above -- you've assigned an entirely separate class C net for your UML sessions; hence the need for NAT and MASQUERADE and so on on the host side. -- ======================================================================== Robert P. J. Day Linux Consulting, Training and Annoying Kernel Pedantry: Have classroom, will lecture. http://crashcourse.ca Waterloo, Ontario, CANADA ======================================================================== |
From: Antoine M. <an...@na...> - 2008-03-06 23:09:12
|
-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA512 Robert P. J. Day wrote: | On Wed, 5 Mar 2008, Antoine Martin wrote: | |> Well, the problem is that if you don't want to use dhcp, you either have |> to edit some config files on the guest or you have to login and bring |> the network up by hand... |> IMO, that's more complicated (and less flexible) than just starting a |> dhcp server instance. |> |> Antoine | | i know what you're talking about here -- at least, let me make sure | i do. | | at the moment, my host system is 192.168.1.2 on the local home | network (router/gateway at 192.168.1.1). if i was setting up UML | networking *properly*, i'd allocate a new network exclusively for all | of my UML guests -- say 10.0.0.0. and i'd set up a DHCP server on my | host that would hand out 10.x.x.x addresses to my UML sessions. i'd | also have to have the host doing NAT to allow those UML sessions | access to the internet, etc, etc. i believe that's what you're | describing at the bottom of the page here, yes? | | http://uml.nagafix.co.uk/ | | however, if i have just the one UML session and i just want some | quick networking, i can do something much faster and uglier, and steal | IP addresses from my current physical network so that i'll have the | following tuntap connection between my host and guest: | | host <----------> UML | | 192.168.1.254 192.168.1.253 | | then, in the UML session, i can make 192.168.1.254 my default gateway, | and i can set up my host to forward IP packets. (all of that requires | manually configuring the UML session, including hard-coding the DNS | server, which would be 192.168.1.1, my router.) | | the above hack does work, but it's admittedly, you know, hacky. and | it certainly doesn't scale well if i want to start supporting multiple | guest UML sessions. | | so, just to make sure i understand, yes, DHCP would clearly be a | cleaner approach, but it *would* involve allocating a new network to | my UML sessions No it does not. You can bind the dhcp server to a specific network interface and make it serve any IP address you like. Using dhcp, you can do all this *without* logging into the guest via the console - no interaction needed. So you can even have the guest start ssh and connect via the network. Cheers Antoine | -- i wouldn't want to have my local network with an | address of 192.168.1.0 and also be giving out DHCP addresses of the | same form to my UML sessions, would i? (it's possible to do that, of | course, but it would be ugly.) | | do i understand this even remotely? | | rday | | p.s. this *appears* to be what you're doing in your setup at the | bottom of that web page again. i note that, when you start a UML | session, you assign the host eth0 an address of 192.168.1.254, which | suggests your local (physical) network is 192.168.1.0 (which is pretty | standard). | | but your DHCP server is handing out addresses of the form 192.168.0.x, | so that seems to agree with what i wrote above -- you've assigned an | entirely separate class C net for your UML sessions; hence the need | for NAT and MASQUERADE and so on on the host side. | -- | | ======================================================================== | Robert P. J. Day | Linux Consulting, Training and Annoying Kernel Pedantry: | Have classroom, will lecture. | | http://crashcourse.ca Waterloo, Ontario, CANADA | ======================================================================== | -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.7 (GNU/Linux) Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org iD8DBQFH0HmLGK2zHPGK1rsRCp4lAJ95ql0JgLrL6DQ200RobNrl6RJstwCfR4el xl4nL0mf78jW3+EGutIKqo0= =w5r6 -----END PGP SIGNATURE----- |
From: Benedict V. <ben...@gm...> - 2008-03-13 09:53:58
|
Robert P. J. Day wrote: <snip> > p.s. this *appears* to be what you're doing in your setup at the > bottom of that web page again. i note that, when you start a UML > session, you assign the host eth0 an address of 192.168.1.254, which > suggests your local (physical) network is 192.168.1.0 (which is pretty > standard). My physical network is 192.168.0.x and i have 2 machines on it. However, i use addresses in the same range for my UML's as i use them mainly to group services (mailserver, webserver, dns and so on). If they were real servers, they would also have an ipaddress in the same range so i don't see why i would use a whole other range of ip's for the umls. Although not the easiest, bridging is also a very nice way to get networking. If you use tuntap, you actually use 2 ip's, one on the host side and one on the uml side. The main advantage of bridging is that you only need one ip address. I ran into problems with it a year or so ago, when a certain bug in the kernel made bridging unusable (at least on my server). The networking was very very slow. Because of that i switched to the tuntap way of networking. I haven't tried bridging since so there's a good chance it works. As for the fact that not much info is around, if think that's not exactely true, it's just very widespread :) A couple of years back i started doing what you are doing, gathering info. I now have a 48Kb textfile with lot's of info dealing with how to compile an uml kernel, a host kernel, networking (tuntap, bridging), startup scripts for the uml's and so on. I haven't put it on the net because it's a working paper, not really a tutorial on how the setup an UML. Regards, Benedict |
From: Jeff D. <jd...@ad...> - 2008-03-05 00:25:25
|
On Tue, Mar 04, 2008 at 05:15:09PM -0500, Robert P. J. Day wrote: > so where can i find those two objects? as i understand it, for me > to set up networking, either the kernel or the root filesystem has to > have networking capability. for example, consider the recipe here: > > http://user-mode-linux.sourceforge.net/network.html > > note how the instructions for the UML guest involve doing a modprobe, You're misreading the output. That's what the uml_net helper is doing on the host (i.e. why would anything be doing a modprobe tun in the UML?). The host output is captured for debuggability in case something goes wrong. A filesystem that automatically brings up a network with access to the outside world isn't doable. The setup is easier when you put the UML on the same network as the host, and that information can't be cooked into the filesystem. Also, there's the requirement that the UML IP address be unique, which requires some sort of knowledge from outside the filesystem. Jeff -- Work email - jdike at linux dot intel dot com |
From: Robert P. J. D. <rp...@cr...> - 2008-03-05 00:38:42
|
On Tue, 4 Mar 2008, Jeff Dike wrote: > On Tue, Mar 04, 2008 at 05:15:09PM -0500, Robert P. J. Day wrote: > > so where can i find those two objects? as i understand it, for me > > to set up networking, either the kernel or the root filesystem has to > > have networking capability. for example, consider the recipe here: > > > > http://user-mode-linux.sourceforge.net/network.html > > > > note how the instructions for the UML guest involve doing a modprobe, > > You're misreading the output. That's what the uml_net helper is doing > on the host (i.e. why would anything be doing a modprobe tun in the > UML?). The host output is captured for debuggability in case > something goes wrong. ah, ok, now it makes more sense. i'll try this again later, thanks. rday -- ======================================================================== Robert P. J. Day Linux Consulting, Training and Annoying Kernel Pedantry: Have classroom, will lecture. http://crashcourse.ca Waterloo, Ontario, CANADA ======================================================================== |
From: Robert P. J. D. <rp...@cr...> - 2008-03-05 01:14:18
|
On Wed, 5 Mar 2008, Antoine Martin wrote: > -----BEGIN PGP SIGNED MESSAGE----- > Hash: SHA512 > > Robert P. J. Day wrote: > | On Tue, 4 Mar 2008, Antoine Martin wrote: > | > |> -----BEGIN PGP SIGNED MESSAGE----- > |> Hash: SHA512 > |> > |> The kernels and filesystems here: > |> http://uml.nagafix.co.uk/ > |> Should all be set to use dhcp network configuration, just start a dhcp > |> server and you should be up and running. > |> > |> Antoine > | > | but for simplicity's sake, i would prefer not to set up a DHCP server > | just yet -- i would prefer to configure that first example of > | networking manually and, step by step, work my way up -- that's the > | whole point of the "recipe" approach. > | > | i've already downloaded, from the nagafix site, the following: > | > | * Fedora8-x86-root_fs.bz2 > | * kernel32-2.6.24.3.bz2 > | > | and, certainly, i can start basic UML with those. so now, the > | question is, what is the exact set of steps to do nothing more than > | network my host and my guest OS, as simply as possible? > Well, the problem is that if you don't want to use dhcp, you either > have to edit some config files on the guest or you have to login and > bring the network up by hand... IMO, that's more complicated (and > less flexible) than just starting a dhcp server instance. > > Antoine that may be true, but it's not the point. in writing out a recipe for how to do something, sometimes it's more informational to start with the more cumbersome and manual approach, only to show how it evolves into an easier and simpler strategy later on. consider the explanation for how to set up simple networking here: http://user-mode-linux.sourceforge.net/network.html the very first line on that web page seems quite clear about what is about to be explained: "The easiest way to get started with UML networking involves nothing special besides adding a switch to the UML command line." ok, fine, then let's get networking running by doing nothing more than "adding a switch to the UML command line." *that's* what i want to do. and yet, no matter what i try, the instructions on that page don't give me networking. consider, as a single example, the suggestion on that page that you can configure the eth0 device thusly if you have a running UML session: $ uml_mconsole umid eth0=tuntap,,,192.168.0.254 if i try that, i get: $ uml_mconsole MwxFu2 eth0=tuntap,,,192.168.1.254 ERR Unknown command $ in short, those instructions simply don't work so there's not much point reading the rest of that page since i now don't trust anything that's written there. what i'm after is fairly simple -- given a kernel and a root filesystem, i want to know how to *manually* configure simple networking between my guest OS and my host OS, as a number of web pages assure me is possible but none of them explain correctly. i don't want to know how to configure automatic networking, i don't want to set up DHCP. i want to start by doing this *manually* so, at the risk of sounding a bit brusque because it's been a long day, unless you are willing to supply the instructions for doing just that, please don't waste my time. i will *eventually* get around to doing the more sophisticated stuff, but that's not what i'm trying to do *now*. in a nutshell, the reason i'm investing my time in trying to write a "recipe" for getting UML running from scratch is because there's nothing on the net that explains how to do that. rday -- ======================================================================== Robert P. J. Day Linux Consulting, Training and Annoying Kernel Pedantry: Have classroom, will lecture. http://crashcourse.ca Waterloo, Ontario, CANADA ======================================================================== |
From: Jon R. <ra...@cs...> - 2008-03-05 01:34:05
|
You can try this blog post I wrote about UML and networking. I wrote it after the fact so it might be missing things but I did do things manually all the way through. http://www.rafkind.com/jon/showproject.php?id=34 Robert P. J. Day wrote: > On Wed, 5 Mar 2008, Antoine Martin wrote: > > >> -----BEGIN PGP SIGNED MESSAGE----- >> Hash: SHA512 >> >> Robert P. J. Day wrote: >> | On Tue, 4 Mar 2008, Antoine Martin wrote: >> | >> |> -----BEGIN PGP SIGNED MESSAGE----- >> |> Hash: SHA512 >> |> >> |> The kernels and filesystems here: >> |> http://uml.nagafix.co.uk/ >> |> Should all be set to use dhcp network configuration, just start a dhcp >> |> server and you should be up and running. >> |> >> |> Antoine >> | >> | but for simplicity's sake, i would prefer not to set up a DHCP server >> | just yet -- i would prefer to configure that first example of >> | networking manually and, step by step, work my way up -- that's the >> | whole point of the "recipe" approach. >> | >> | i've already downloaded, from the nagafix site, the following: >> | >> | * Fedora8-x86-root_fs.bz2 >> | * kernel32-2.6.24.3.bz2 >> | >> | and, certainly, i can start basic UML with those. so now, the >> | question is, what is the exact set of steps to do nothing more than >> | network my host and my guest OS, as simply as possible? >> > > >> Well, the problem is that if you don't want to use dhcp, you either >> have to edit some config files on the guest or you have to login and >> bring the network up by hand... IMO, that's more complicated (and >> less flexible) than just starting a dhcp server instance. >> >> Antoine >> > > that may be true, but it's not the point. in writing out a recipe > for how to do something, sometimes it's more informational to start > with the more cumbersome and manual approach, only to show how it > evolves into an easier and simpler strategy later on. > > consider the explanation for how to set up simple networking here: > > http://user-mode-linux.sourceforge.net/network.html > > the very first line on that web page seems quite clear about what is > about to be explained: > > "The easiest way to get started with UML networking involves nothing > special besides adding a switch to the UML command line." > > ok, fine, then let's get networking running by doing nothing more > than "adding a switch to the UML command line." *that's* what i want > to do. and yet, no matter what i try, the instructions on that page > don't give me networking. > > consider, as a single example, the suggestion on that page that you > can configure the eth0 device thusly if you have a running UML > session: > > $ uml_mconsole umid eth0=tuntap,,,192.168.0.254 > > if i try that, i get: > > $ uml_mconsole MwxFu2 eth0=tuntap,,,192.168.1.254 > ERR Unknown command > $ > > in short, those instructions simply don't work so there's not much > point reading the rest of that page since i now don't trust anything > that's written there. > > what i'm after is fairly simple -- given a kernel and a root > filesystem, i want to know how to *manually* configure simple > networking between my guest OS and my host OS, as a number of web > pages assure me is possible but none of them explain correctly. > > i don't want to know how to configure automatic networking, i don't > want to set up DHCP. i want to start by doing this *manually* so, at > the risk of sounding a bit brusque because it's been a long day, > unless you are willing to supply the instructions for doing just that, > please don't waste my time. i will *eventually* get around to doing > the more sophisticated stuff, but that's not what i'm trying to do > *now*. > > in a nutshell, the reason i'm investing my time in trying to write a > "recipe" for getting UML running from scratch is because there's > nothing on the net that explains how to do that. > > rday > -- > > > ======================================================================== > Robert P. J. Day > Linux Consulting, Training and Annoying Kernel Pedantry: > Have classroom, will lecture. > > http://crashcourse.ca Waterloo, Ontario, CANADA > ======================================================================== > > ------------------------------------------------------------------------- > This SF.net email is sponsored by: Microsoft > Defy all challenges. Microsoft(R) Visual Studio 2008. > http://clk.atdmt.com/MRT/go/vse0120000070mrt/direct/01/ > _______________________________________________ > User-mode-linux-user mailing list > Use...@li... > https://lists.sourceforge.net/lists/listinfo/user-mode-linux-user > |
From: Robert P. J. D. <rp...@cr...> - 2008-03-05 01:36:55
|
On Tue, 4 Mar 2008, Jon Rafkind wrote: > You can try this blog post I wrote about UML and networking. I wrote it > after the fact so it might be missing things but I did do things > manually all the way through. > > http://www.rafkind.com/jon/showproject.php?id=34 ok, i'll give it a shot, thanks. maybe not tonight but i'll get to it. rday -- ======================================================================== Robert P. J. Day Linux Consulting, Training and Annoying Kernel Pedantry: Have classroom, will lecture. http://crashcourse.ca Waterloo, Ontario, CANADA ======================================================================== |
From: Jeff D. <jd...@ad...> - 2008-03-05 02:35:22
|
On Tue, Mar 04, 2008 at 08:14:09PM -0500, Robert P. J. Day wrote: > consider, as a single example, the suggestion on that page that you > can configure the eth0 device thusly if you have a running UML > session: > > $ uml_mconsole umid eth0=tuntap,,,192.168.0.254 > > if i try that, i get: > > $ uml_mconsole MwxFu2 eth0=tuntap,,,192.168.1.254 > ERR Unknown command Oops, fixed. That should have been uml_mconsole umid config eth0=tuntap,,,192.168.0.254 of course. Jeff -- Work email - jdike at linux dot intel dot com |
From: Robert P. J. D. <rp...@cr...> - 2008-03-05 09:40:04
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On Tue, 4 Mar 2008, Jeff Dike wrote: > On Tue, Mar 04, 2008 at 08:14:09PM -0500, Robert P. J. Day wrote: > > consider, as a single example, the suggestion on that page that you > > can configure the eth0 device thusly if you have a running UML > > session: > > > > $ uml_mconsole umid eth0=tuntap,,,192.168.0.254 > > > > if i try that, i get: > > > > $ uml_mconsole MwxFu2 eth0=tuntap,,,192.168.1.254 > > ERR Unknown command > > Oops, fixed. That should have been > uml_mconsole umid config eth0=tuntap,,,192.168.0.254 > of course. ah, now we're making progress, thanks. i apologize for sounding a bit snippy last night but i'd just spent a few hours perusing the net for newbie-level intro stuff on UML and was getting increasingly frustrated by the inconsistent and self-contradictory content i was running across. and the above is just another example of what would be a bit maddening to someone just trying to get some simple networking. so, let me quickly sum up what i've got running. for the purposes of experimentation, since i'm on a fedora 8 system, i've grabbed from http://uml.nagafix.co.uk/ the following: * Fedora8-x86-root_fs.bz2 * kernel32-2.6.24.3.bz2 and verified quickly that, yes, i can run a UML session with those. so far, so good. and now, what it took to get networking running in a very simple way: 1) start UML session with no networking parameters 2) on host, run: $ uml_mconsole DywKnv config eth0=tuntap,,,192.168.1.254 OK $ 3) in the UML session, enable eth0 thusly: UML# ifconfig eth0 192.168.1.253 up UML# ifconfig eth0 eth0 Link encap:Ethernet HWaddr 9E:14:C3:96:2D:4A inet addr:192.168.1.253 Bcast:192.168.1.255 Mask:255.255.255.0 inet6 addr: fe80::9c14:c3ff:fe96:2d4a/64 Scope:Link UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets:25 errors:0 dropped:0 overruns:0 frame:0 TX packets:4 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:3846 (3.7 KiB) TX bytes:308 (308.0 b) Interrupt:5 UML# 4) from the host, can i ping the UML session? $ ping 192.168.1.253 PING 192.168.1.253 (192.168.1.253) 56(84) bytes of data. 64 bytes from 192.168.1.253: icmp_seq=1 ttl=64 time=0.957 ms 64 bytes from 192.168.1.253: icmp_seq=2 ttl=64 time=0.229 ms ... yee ha! and what about ... 5) from the UML session, can i ping the host? UML# ping 192.168.1.254 ping: error while loading shared libraries: libidn.so.11: \ cannot open shared object file: No such file or directory UML# hmmmm ... not so good, but ssh still seems to work: UML# ssh 192.168.1.254 ... success ... and that's all i was after for the time being. so we're making progress, and i'll document the above at my wiki. but first, a few questions about the above: a) once i run the "uml_mconsole" command on the host, is there a way to verify the result of that operation? running "ifconfig" doesn't show me any difference, so how could one verify that that operation finished correctly? "ifconfig" won't show a working "tap0" interface until networking is brought up in the UML session, so is there any indication at all on the host side until that happens? b) what must be true about both the host kernel and the guest kernel for simple networking to work? i can't think of anything more frustrating for a beginner than to fight with networking for a while, only to learn that either his host or guest kernel wasn't configured and built with the required functionality. so it would be nice to have a checklist for both kernels. more later. rday -- ======================================================================== Robert P. J. Day Linux Consulting, Training and Annoying Kernel Pedantry: Have classroom, will lecture. http://crashcourse.ca Waterloo, Ontario, CANADA ======================================================================== |
From: Jeff D. <jd...@ad...> - 2008-03-05 19:42:08
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On Wed, Mar 05, 2008 at 04:39:50AM -0500, Robert P. J. Day wrote: > a) once i run the "uml_mconsole" command on the host, is there a way > to verify the result of that operation? running "ifconfig" doesn't > show me any difference, so how could one verify that that operation > finished correctly? "ifconfig" won't show a working "tap0" interface > until networking is brought up in the UML session, so is there any > indication at all on the host side until that happens? The "OK" from uml_mconsole means the operation succeeded. And by "the operation", I mean the addition of a new interface to the UML. Since that is strictly internal to the UML (some types of interfaces, i.e. daemon and mcast, are invisible to the host as networking), there can't be any other indication on the host that anything happened. > b) what must be true about both the host kernel and the guest kernel > for simple networking to work? i can't think of anything more > frustrating for a beginner than to fight with networking for a while, > only to learn that either his host or guest kernel wasn't configured > and built with the required functionality. so it would be nice to > have a checklist for both kernels. Networking on both sides, TUN/TAP available on the host. The UML utilities installed on the host. Jeff -- Work email - jdike at linux dot intel dot com |
From: Robert P. J. D. <rp...@cr...> - 2008-03-06 08:14:59
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On Wed, 5 Mar 2008, Jeff Dike wrote: > On Wed, Mar 05, 2008 at 04:39:50AM -0500, Robert P. J. Day wrote: > > a) once i run the "uml_mconsole" command on the host, is there a > > way to verify the result of that operation? running "ifconfig" > > doesn't show me any difference, so how could one verify that that > > operation finished correctly? "ifconfig" won't show a working > > "tap0" interface until networking is brought up in the UML > > session, so is there any indication at all on the host side until > > that happens? > > The "OK" from uml_mconsole means the operation succeeded. And by > "the operation", I mean the addition of a new interface to the UML. > Since that is strictly internal to the UML (some types of > interfaces, i.e. daemon and mcast, are invisible to the host as > networking), there can't be any other indication on the host that > anything happened. ok, i suspected as much, i just wanted to make sure, thanks. i did warn you that some of these would be newbie-level questions. :-) rday -- ======================================================================== Robert P. J. Day Linux Consulting, Training and Annoying Kernel Pedantry: Have classroom, will lecture. http://crashcourse.ca Waterloo, Ontario, CANADA ======================================================================== |