Proxmox DHCP relay between network

bobdocland

New Member
Feb 3, 2015
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0
1
Hi all,

I've few differents subnets on my Proxmox server. The goal is to simulate a real infrastructure.
To sum up, I've:
- LAN server subnet with dhcp,ntp, ldap, mail, intranet web servers (vmbr1)
- DMZ subnet with DNS, VPN servers (vmbr2)
- LAN client subnet with client station (vmbr3)

Critical servers (dns,dhcp,ntp,ldap) are configured with static IP, others servers and clients stations should obtain IP by DHCP.
The server DHCP run well on LAN server subnet, but DHCP request from other subnet don't reach the DHCP server.

I think the problem is that there is no DHCP relay. I haven't found any information to do this directly with Proxmox.

Is anyone ever encountered this problem or have a solution for me ?

Thank you in advance.
Bye
 
Use and setup ip-forward, iptables and you need some brain to setup either NAT von the private site to the public site of yout network. Without NAT you need routes back to your private site of your network on all router.

A 'local' dhcpd is fast and easy setup for every network segment.
You can start with isc-dhcp-server, but is end of maintenance of end 2022.

# https://www.isc.org/dhcp/
# https://kb.isc.org/docs/kea-build-on-debian
 
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You can also create a VM with pfsense or opnsense. You can configure dhcp for every network or if you prefer a dhcp on a NET and a dhcp relay on the others NET.
 
we are currently working on official dhcp integration in sdn + ipam, maybe a beta will be available for pve 8.1.
I have a 3 host cluster in HA mode
each host has two nics.
1 - managment and bridge
2 - storage network no bridge
I have created a bridge with no physical nic association.
I have also create a VXLAN (vlan10) object that includes the 3 hosts in the "nodes" and the 3 host IP in the peers.
I have created a VNET (vnet10) associated with the VXLAN and taged as "10"
all vlan aware where applicable.
I have opnsense using the "vnet10" as it's LAN nic. I can migrate VMs, and they get to the internet and manage the opnsense.
I have an ISC "GLASS" DHCP server on "vnet10" as well.
I wan't to know what I need to do to set up "dhcp relay" , would this be a proxmox limitation or opnsense?
 
I have a 3 host cluster in HA mode
each host has two nics.
1 - managment and bridge
2 - storage network no bridge
I have created a bridge with no physical nic association.
I have also create a VXLAN (vlan10) object that includes the 3 hosts in the "nodes" and the 3 host IP in the peers.
I have created a VNET (vnet10) associated with the VXLAN and taged as "10"
all vlan aware where applicable.
I have opnsense using the "vnet10" as it's LAN nic. I can migrate VMs, and they get to the internet and manage the opnsense.
I have an ISC "GLASS" DHCP server on "vnet10" as well.
I wan't to know what I need to do to set up "dhcp relay" , would this be a proxmox limitation or opnsense?
so I think it might be the PVE host firewall as it worked after I disabled all PVE firewalls. This is sorta is confusing as a vxlan is a tunneling vlan object.....
 
dhcp is simply a service somewhere running on the same subnet than your vm (which is sending the dhcp request), then it's forwarding (relaying) the dhcp requet to your central dhcp server.


if you have " ISC "GLASS" DHCP server on "vnet10" as well." , so why do you need a relay ? as you already have the dhcp server on the same vnet/subnet.
 

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