[pve-devel] [WIP v2 cluster/network/manager/qemu-server/container 00/10] Add support for DHCP servers to SDN

Stefan Hanreich s.hanreich at proxmox.com
Tue Oct 17 15:54:57 CEST 2023

This is a WIP patch series, since I will be gone for 3 weeks and wanted to
share my current progress with the DHCP support for SDN.

This patch series adds support for automatically deploying dnsmasq as a DHCP
server to a simple SDN Zone.

While certainly not 100% polished on some ends (looking at restarting systemd
services in particular), the general idea behind the mechanism shows. I wanted
to gather some feedback on how I approached designing the plugins and the
config regeneration process before comitting to this design by creating an API
and UI around it.

You need to install dnsmasq (and disable it afterwards):

  apt install dnsmasq && systemctl disable --now dnsmasq

You can use the following example configuration for deploying a DHCP server in
a SDN subnet:


  dnsmasq: nat


  simple: DHCPNAT
          ipam pve


  vnet: dhcpnat
          zone DHCPNAT


  subnet: DHCPNAT-
          vnet dhcpnat
          dhcp-range server=nat,start-address=,end-address=
          snat 1

Then apply the SDN configuration:

  pvesh set /cluster/sdn

You need to apply the SDN configuration once after adding the dhcp-range lines
to the configuration, since the running configuration is used for managing
DHCP. It will not work otherwise!

For testing it can be helpful to monitor the following files (e.g. with watch)
to find out what is happening
  * /etc/dnsmasq.d/<dhcp_id>/ethers (on each node)
  * /etc/pve/priv/ipam.db

Changes from v1 -> v2:
  * added hooks for handling DHCP when starting / stopping / .. VMs and CTs
  * Get an IP from IPAM and register that IP in the DHCP server
    (pve only for now)
  * remove lease-time, since it is now infinite and managed by the VM lifecycle
  * add hooks for setting & deleting DHCP mappings to DHCP plugins
  * modified interface of the abstract class to reflect new requirements
  * added helpers in existing SDN classes
  * simplified DHCP configuration settings


Stefan Hanreich (1):
  cluster files: add dhcp.cfg

 src/PVE/Cluster.pm  | 1 +
 src/pmxcfs/status.c | 1 +
 2 files changed, 2 insertions(+)


Stefan Hanreich (6):
  subnets: vnets: preparations for DHCP plugins
  dhcp: add abstract class for DHCP plugins
  dhcp: subnet: add DHCP options to subnet configuration
  dhcp: add DHCP plugin for dnsmasq
  ipam: Add helper methods for DHCP to PVE IPAM
  dhcp: regenerate config for DHCP servers on reload

 debian/control                         |   1 +
 src/PVE/Network/SDN.pm                 |  11 +-
 src/PVE/Network/SDN/Dhcp.pm            | 192 +++++++++++++++++++++++++
 src/PVE/Network/SDN/Dhcp/Dnsmasq.pm    | 186 ++++++++++++++++++++++++
 src/PVE/Network/SDN/Dhcp/Makefile      |   8 ++
 src/PVE/Network/SDN/Dhcp/Plugin.pm     |  83 +++++++++++
 src/PVE/Network/SDN/Ipams/PVEPlugin.pm |  64 +++++++++
 src/PVE/Network/SDN/Makefile           |   3 +-
 src/PVE/Network/SDN/SubnetPlugin.pm    |  32 +++++
 src/PVE/Network/SDN/Subnets.pm         |  43 ++++--
 src/PVE/Network/SDN/Vnets.pm           |  27 ++--
 11 files changed, 622 insertions(+), 28 deletions(-)
 create mode 100644 src/PVE/Network/SDN/Dhcp.pm
 create mode 100644 src/PVE/Network/SDN/Dhcp/Dnsmasq.pm
 create mode 100644 src/PVE/Network/SDN/Dhcp/Makefile
 create mode 100644 src/PVE/Network/SDN/Dhcp/Plugin.pm


Stefan Hanreich (1):
  sdn: regenerate DHCP config on reload

 PVE/API2/Network.pm | 1 +
 1 file changed, 1 insertion(+)


Stefan Hanreich (1):
  sdn: dhcp: add DHCP setup to vm-network-scripts

 PVE/QemuServer.pm                 | 14 ++++++++++++++
 vm-network-scripts/pve-bridge     |  3 +++
 vm-network-scripts/pve-bridgedown | 19 +++++++++++++++++++
 3 files changed, 36 insertions(+)


Stefan Hanreich (1):
  sdn: dhcp: setup DHCP mappings in LXC hooks

 src/PVE/LXC.pm            | 10 ++++++++++
 src/lxc-pve-poststop-hook |  1 +
 src/lxc-pve-prestart-hook |  9 +++++++++
 3 files changed, 20 insertions(+)

Summary over all repositories:
  20 files changed, 681 insertions(+), 28 deletions(-)

murpp v0.4.0

More information about the pve-devel mailing list