Re: [libvirt] [RFC, PATCH] network: add 'netboot' option to dhcp config
On 09/15/2009 01:01 AM, Jeremy Kerr wrote: Hi Paolo, Since there is only one TFTP server running in the network IIRC, it's possible to have more than one: the Server-Name (id 66) of the DHCP response specifies which. However, we probably only ever want to start one server, so the tag should work fine. Yes, what I meant is that in general the TFTP server started by libvirt will run on the address provided by /network/i...@address. So libvirt can only start one TFTP server even though in the future it might support multiple DHCP ranges. In this case, some ranges may not support BOOTP and some may, and they can give different boot files, but all must share a single dnsmasq-provided TFTP server (using a server attribute would be fine; but that TFTP server will not be started by libvirt). This can be seen from the fact that BOOTP is nothing more than a few options within a DHCP packet (i.e. ), but TFTP binds on a completely different port and could be a separate process (hence is a sibling of ). dnsmasq is special. , it is not possible to specify different roots for different dhcp ranges. I think the schema should be If you want it to be specific to the range, shouldn't it be within the tag? Currently the code will only parse one tag. No, I want it to be specific to the _network_, since it will bind to /network/i...@address. One thing that I've tried to keep in mind is that the tftp service may be provided by a separate machine in the network, so we may need some way in the future to represent that - maybe no tag That's already implemented by my patch, and can be used with an external TFTP server, for example started via (x)inetd. and use server="w.x.y.z" in the bootp tag. Also, would be cool to have separate files for different hosts, but that may be thinking too far ahead at this stage :) Yes. That's something you'd get for free if libvirt supported multiple DHCP ranges. Paolo -- Libvir-list mailing list Libvir-list@redhat.com https://www.redhat.com/mailman/listinfo/libvir-list
Re: [libvirt] [RFC, PATCH] network: add 'netboot' option to dhcp config
Hi Paolo, > Since there is only one TFTP server running in the network IIRC, it's possible to have more than one: the Server-Name (id 66) of the DHCP response specifies which. However, we probably only ever want to start one server, so the tag should work fine. > , it is not > possible to specify different roots for different dhcp ranges. I think > the schema should be > > > > > > > > If you want it to be specific to the range, shouldn't it be within the tag? Currently the code will only parse one tag. Otherwise, looks fine - I'm happy with either method. One thing that I've tried to keep in mind is that the tftp service may be provided by a separate machine in the network, so we may need some way in the future to represent that - maybe no tag, and use server="w.x.y.z" in the bootp tag. Also, would be cool to have separate files for different hosts, but that may be thinking too far ahead at this stage :) Cheers, Jeremy -- Libvir-list mailing list Libvir-list@redhat.com https://www.redhat.com/mailman/listinfo/libvir-list
Re: [libvirt] [RFC, PATCH] network: add 'netboot' option to dhcp config
On 09/11/2009 06:47 AM, Jeremy Kerr wrote: Currently, libvirtd will start a dnsmasq process for the virtual network, but (aside from killing the dnsmasq process and replacing it), there's no way to define tftp boot options. This change introduces a 'netboot' tag to the dhcp configuration: default When root= and file= attributes are present, these are passed to the arguments to dnsmasq: dnsmasq [...] --enable-tftp --tftp-root /srv/tftp --dhcp-boot pxeboot.img At present, only local tftp servers are supported (ie, dnsmasq runs as the tftp server), but we could improve this in future by adding a server= attribute. Since there is only one TFTP server running in the network, it is not possible to specify different roots for different dhcp ranges. I think the schema should be where in the future the bootp argument could grow a server attribute as mentioned by Jeremy. Paolo -- Libvir-list mailing list Libvir-list@redhat.com https://www.redhat.com/mailman/listinfo/libvir-list
Re: gPXE (was Re: [libvirt] [RFC,PATCH] network: add 'netboot' option to dhcp config)
On Fri, 2009-09-11 at 09:44 +0100, Tom Hughes wrote: > > I very much like this idea - e.g. I'd really like to have this to give > > people simple instructions for testing gPXE in next week's Fedora Test > > Day. > > On the subject of gPXE has anybody else found that it doesn't seem to be > working at all? > > I'm using the virt-preview packages on F11 and ever since qemu switched > to use gPXE network booting has been completely broken. I get the gPXE > banner message appear and then nothing happens. Monitoring the network > shows no signs of any DHCP requests being sent at all. It's probably this: https://bugzilla.redhat.com/512358 It's fixed in the F-12 kernel, but we need that fix backported to F-11. Cheers, Mark. -- Libvir-list mailing list Libvir-list@redhat.com https://www.redhat.com/mailman/listinfo/libvir-list
gPXE (was Re: [libvirt] [RFC,PATCH] network: add 'netboot' option to dhcp config)
I very much like this idea - e.g. I'd really like to have this to give people simple instructions for testing gPXE in next week's Fedora Test Day. On the subject of gPXE has anybody else found that it doesn't seem to be working at all? I'm using the virt-preview packages on F11 and ever since qemu switched to use gPXE network booting has been completely broken. I get the gPXE banner message appear and then nothing happens. Monitoring the network shows no signs of any DHCP requests being sent at all. Tom -- Tom Hughes (t...@compton.nu) http://www.compton.nu/ -- Libvir-list mailing list Libvir-list@redhat.com https://www.redhat.com/mailman/listinfo/libvir-list
Re: [libvirt] [RFC,PATCH] network: add 'netboot' option to dhcp config
On Fri, Sep 11, 2009 at 09:22:09AM +0100, Mark McLoughlin wrote: > On Fri, 2009-09-11 at 14:47 +1000, Jeremy Kerr wrote: > > Currently, libvirtd will start a dnsmasq process for the virtual > > network, but (aside from killing the dnsmasq process and replacing it), > > there's no way to define tftp boot options. > > > > This change introduces a 'netboot' tag to the dhcp configuration: > > > > > >default > > > > > > > > > > > > > > > > > > > > > > When root= and file= attributes are present, these are passed to the > > arguments to dnsmasq: > > > > dnsmasq [...] --enable-tftp --tftp-root /srv/tftp --dhcp-boot pxeboot.img > > > > At present, only local tftp servers are supported (ie, dnsmasq runs as > > the tftp server), but we could improve this in future by adding a > > server= attribute. > > I very much like this idea - e.g. I'd really like to have this to give > people simple instructions for testing gPXE in next week's Fedora Test > Day. > > The argument was made before that it's pointless to use PXE like this > when you can just explicitly configure a kernel/initrd, but that misses > the point that sometimes you do explicitly want to use PXE, even just > for testing purposes. > > Patch looks good to me too, ACK I like the idea too. But this opens the door to outside access or just limits it to the guest ? In any case make sure you have an up to date dnsmasq https://cert.belnet.be/belnetadvisories/rhsa-20091238-01-important-dnsmasq-security-update Daniel -- Daniel Veillard | libxml Gnome XML XSLT toolkit http://xmlsoft.org/ dan...@veillard.com | Rpmfind RPM search engine http://rpmfind.net/ http://veillard.com/ | virtualization library http://libvirt.org/ -- Libvir-list mailing list Libvir-list@redhat.com https://www.redhat.com/mailman/listinfo/libvir-list
Re: [libvirt] [RFC,PATCH] network: add 'netboot' option to dhcp config
On Fri, 2009-09-11 at 09:22 +0100, Mark McLoughlin wrote: > On Fri, 2009-09-11 at 14:47 +1000, Jeremy Kerr wrote: > > Currently, libvirtd will start a dnsmasq process for the virtual > > network, but (aside from killing the dnsmasq process and replacing it), > > there's no way to define tftp boot options. > > > > This change introduces a 'netboot' tag to the dhcp configuration: > > > > > >default > > > > > > > > > > > > > > > > > > > > > > When root= and file= attributes are present, these are passed to the > > arguments to dnsmasq: > > > > dnsmasq [...] --enable-tftp --tftp-root /srv/tftp --dhcp-boot pxeboot.img > > > > At present, only local tftp servers are supported (ie, dnsmasq runs as > > the tftp server), but we could improve this in future by adding a > > server= attribute. > > I very much like this idea - e.g. I'd really like to have this to give > people simple instructions for testing gPXE in next week's Fedora Test > Day. > > The argument was made before that it's pointless to use PXE like this > when you can just explicitly configure a kernel/initrd, but that misses > the point that sometimes you do explicitly want to use PXE, even just > for testing purposes. > > Patch looks good to me too, ACK Previous discussion was here: http://www.redhat.com/archives/fedora-virt/2009-June/msg00154.html Cheers, Mark. -- Libvir-list mailing list Libvir-list@redhat.com https://www.redhat.com/mailman/listinfo/libvir-list
Re: [libvirt] [RFC,PATCH] network: add 'netboot' option to dhcp config
On Fri, 2009-09-11 at 14:47 +1000, Jeremy Kerr wrote: > Currently, libvirtd will start a dnsmasq process for the virtual > network, but (aside from killing the dnsmasq process and replacing it), > there's no way to define tftp boot options. > > This change introduces a 'netboot' tag to the dhcp configuration: > > >default > > > > > > > > > > > When root= and file= attributes are present, these are passed to the > arguments to dnsmasq: > > dnsmasq [...] --enable-tftp --tftp-root /srv/tftp --dhcp-boot pxeboot.img > > At present, only local tftp servers are supported (ie, dnsmasq runs as > the tftp server), but we could improve this in future by adding a > server= attribute. I very much like this idea - e.g. I'd really like to have this to give people simple instructions for testing gPXE in next week's Fedora Test Day. The argument was made before that it's pointless to use PXE like this when you can just explicitly configure a kernel/initrd, but that misses the point that sometimes you do explicitly want to use PXE, even just for testing purposes. Patch looks good to me too, ACK Cheers, Mark. -- Libvir-list mailing list Libvir-list@redhat.com https://www.redhat.com/mailman/listinfo/libvir-list
