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

[DERUMIER, Alexandre]

Hi Stefan,

Thanks for sharing !

I'll try to deeply test it this week or next week.

Maybe try to see if we can use pve ipam as cache in front of external
ipam.



-------- Message initial --------
De: Stefan Hanreich <s.hanreich at proxmox.com>
Répondre à: Proxmox VE development discussion <pve-
devel at lists.proxmox.com>
À: pve-devel at lists.proxmox.com
Objet: [pve-devel] [WIP v2 cluster/network/manager/qemu-
server/container 00/10] Add support for DHCP servers to SDN
Date: 17/10/2023 15:54:57

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:

/etc/pve/sdn/dhcp.cfg:

  dnsmasq: nat


/etc/pve/sdn/zones.cfg:

  simple: DHCPNAT
          ipam pve


/etc/pve/sdn/vnets.cfg:

  vnet: dhcpnat
          zone DHCPNAT


/etc/pve/sdn/subnets.cfg:

  subnet: DHCPNAT-10.1.0.0-16
          vnet dhcpnat
          dhcp-dns-server 10.1.0.1
          dhcp-range server=nat,start-address=10.1.0.100,end-
address=10.1.0.200
          gateway 10.1.0.1
          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



pve-cluster:

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

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


pve-network:

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


pve-manager:

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

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


qemu-server:

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(+)


pve-container:

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(-)