No DHCP through vmbr

dukynuky

Active Member
Jun 28, 2019
3
0
41
41
hi,

i have a problem with my proxmox home server.

Modem - seperate proxmox nic - vmbr1 - pfsense

i cant get pfsense to receive a IP with DHCP from the modem. In tcpdump i can see the request on pfsense, on the vmbr and on the physical interface.
The reply only on physical and vmbr. Yes i configured the same mac as on the physical networkcard on the virtual one on the vm.

When i activate dhcp on physical on the proxmox host, dhcp is working. Same on the vmbr1. Pfsense cant get the IP. I already used a plane debian connected to vmbr and it isnt working to.

Now i have no clue, where to look next.

On Vm tcpdump:
13:49:51.334664 IP 0.0.0.0.68 > 255.255.255.255.67: BOOTP/DHCP, Request from 00:23:55:7c:16:82, length 300
13:49:59.347717 IP 0.0.0.0.68 > 255.255.255.255.67: BOOTP/DHCP, Request from 00:23:55:7c:16:82, length 300

On proxmox host tcpdump vmbr1:
13:49:51.331465 IP 0.0.0.0.68 > 255.255.255.255.67: BOOTP/DHCP, Request from 00:23:55:7c:16:82, length 300
13:49:51.347901 IP 83.169.185.2.67 > 91.45.155.192.68: BOOTP/DHCP, Reply, length 308
13:49:59.344535 IP 0.0.0.0.68 > 255.255.255.255.67: BOOTP/DHCP, Request from 00:23:55:7c:16:82, length 300
13:49:59.368725 IP 83.169.185.2.67 > 91.45.155.192.68: BOOTP/DHCP, Reply, length 308

proxmox network config:

iface enp4s0 inet manual
auto vmbr1
iface vmbr1 inet manual
bridge-ports enp4s0
bridge-stp off
bridge-fd 0


Edit: i can see ARP requests from the cable network behind the modem on the vm interface. only the dhcp replys seems to be getting lost on the proxmox host

thanks

dukynuky
 
Last edited:
Detailed packet info from proxmox host vmbr1:

Code:
14:41:32.285841 IP (tos 0x10, ttl 128, id 0, offset 0, flags [none], proto UDP (17), length 328)
    0.0.0.0.68 > 255.255.255.255.67: BOOTP/DHCP, Request from 00:23:55:7c:16:82, length 300, xid 0x7112d58c, secs 17,                                                          Flags [none]
          Client-Ethernet-Address 00:23:55:7c:16:82
          Vendor-rfc1048 Extensions
            Magic Cookie 0x63825363
            DHCP-Message Option 53, length 1: Discover
            Client-ID Option 61, length 7: ether 00:23:55:7c:16:82
            Hostname Option 12, length 7: "pfSense"
            Parameter-Request Option 55, length 10:
              Subnet-Mask, BR, Time-Zone, Classless-Static-Route
              Default-Gateway, Domain-Name, Domain-Name-Server, Hostname
              Option 119, MTU
14:41:32.304787 IP (tos 0x0, ttl 64, id 0, offset 0, flags [none], proto UDP (17), length 336)
    83.169.185.2.67 > 91.45.155.192.68: BOOTP/DHCP, Reply, length 308, xid 0x7112d58c, Flags [none]
          Your-IP 91.45.155.192
          Gateway-IP 83.169.166.98
          Client-Ethernet-Address 00:23:55:7c:16:82
          Vendor-rfc1048 Extensions
            Magic Cookie 0x63825363
            DHCP-Message Option 53, length 1: Offer
            Server-ID Option 54, length 4: 83.169.185.2
            Lease-Time Option 51, length 4: 3958
            Subnet-Mask Option 1, length 4: 255.255.255.0
            BR Option 28, length 4: 91.45.155.255
            Default-Gateway Option 3, length 4: 91.45.155.254
            Domain-Name-Server Option 6, length 8: 83.169.185.33,83.169.185.97
            Hostname Option 12, length 22: "x1-6-00-23-55-7c-16-82"
 
Dont ask how and why.. it is working now.. just did the 1000 restart of the proxmox host...
 

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