[pve-devel] internal dhcp server, where to put dhcp configuration ?

[Alexandre DERUMIER]

>>My thought is that we only implement dhcp for routed mode, and configuration 
>>can be obtained from VM config. 

only routed mode ? I would like also have dhcp on bridged and nat network.
I agreed to have nic ip configuration in vm, but when you launch dnsmasq, you need to specify the network range for the bridge.
(Or we need to compute the ranges from the vms configurations)


Currently libvirt define the dhcp range on each bridge

http://libvirt.org/formatnetwork.html

>>Running a full featured dhcp server on a bridge is 
>>something different for me. Please can you clarify what usage scenario 
>>do you think about exactly? 

What I have in mind is at least basic ip auto-configuration of network card in any case (bridge,routed,nat).
including gateway,dns-server (option domain-name-servers), domain (option domain-name ).


with for bridge+nat, dhcp leases across nodes to keep the ip configuration between live migration



How do you see things on your side ?


----- Mail original ----- 

De: "Dietmar Maurer" <dietmar at proxmox.com> 
À: "Alexandre DERUMIER" <aderumier at odiso.com>, "pve.proxmox.com" <pve-devel at pve.proxmox.com> 
Envoyé: Jeudi 22 Août 2013 17:21:33 
Objet: RE: [pve-devel] internal dhcp server, where to put dhcp configuration ? 

> I'll try to begin to look for dhcp implementation. 
> 
> I don't known where to put dhcp configuration. 
> 
> 
> 1) define it in /etc/network/interfaces in each bridge config 
> But that mean that we need to do it for each server 
> 
> 2) define it in a global /etc/pve/dhcp.cfg. 
> vmbrO = dhcp range X.X.X.X/24, gateway=... 
> vmbr1 = dhcp range X.X.X.X/24 gateway=... 
> .... 
> 
> 
> For bridge and nat mode, that make sense to share the same dhcp config for 
> the bridge, as when you live migrate you need to keep your ip lease. 
> 
> 
> For routed mode, the gateway should be different for each host. (gateway is 
> the host ip). 
> (So, I don't known if live migrate work good with routed mode, we need to 
> renew the dhcp, maybe unplug/plug the virtual nic cable) 

My thought is that we only implement dhcp for routed mode, and configuration 
can be obtained from VM config. 

> Also, I would like add ip,mask,gateway to netX vm param, for lease 
> reservation and override bridge dhcp params. 
> (don't known if we need to allow to specify all dhcp options here) 

Running a full featured dhcp server on a bridge is 
something different for me. Please can you clarify what usage scenario 
do you think about exactly?