Forum Discussion

_pre_'s avatar
_pre_
Icon for Nimbostratus rankNimbostratus
Jan 08, 2021

Relaying netboot/bootp/DHCP traffic for VPN user

Is there any way we could relay DHCP/bootp traffic for VPN users?   We have Mac installed with parallels to run windows 10. While the MAC is in the office we have the ability to re-image the VM...
application delivery
BIG-IP Access Policy Manager (APM)
LTM
vpn
Dave_W's avatar
Dave_W
Icon for Employee rankEmployee
Jan 15, 2021

So with the client connected via VPN (APM Network Access) I would think so. Typically for accessing remote VPN connected clients you want to go into the APM Network Access configuration and disable SNAT. This means the source of the traffic over the VPN would now be on of the IPs assigned to the client via the Network Access Lease Pool.

 

Keep mind if this is a unique Lease Pool Address/Subnet (i.e. does not exist on your network) you would need to add routes on your network to send the traffic back to APM or if Lease Pool Address/Subnet addresses already exist on your network you would need to enable Proxy ARP in the APM Network Access configuration.

_pre_'s avatar
_pre_
Icon for Nimbostratus rankNimbostratus
Feb 04, 2021

Hi Dave,

Thanks in advance!

SNAT is disabled and Proxy ARP is enabled and I can connect to the client IP assigned by APM ( see configuration below ).

The question is can we relay broadcast traffic from the client to specific IP outside the APM network?

Just to be more specific :

When the VirtualMachine it send DHCPDISCOVER message on the network using the destination address 255.255.255.255.

How do we capture this broadcast message so that we can relay it to the appropriate server that lives on the other side of the tunnel? 

apm resource network-access vpn_profile {
    address-space-exclude-dns-name { }
    address-space-exclude-subnet { }
    address-space-include-subnet { }
    address-space-local-subnets-excluded true
    application-launch-warning false
    client-interface-speed 2147483648
    customization-group vpn_profile_resource_network_access_customization
    dns-enforce-search-order false
    dns-primary x.x.x.x
    dns-register-connection true
    dns-secondary x.x.x.x
    dns-suffix example.com
    leasepool-name vpn-ict
    microsoft-network-server true
    optimized-app { }
    preserve-source-port-strict all
    provide-client-cert false
    proxy-arp true
    snat none
    split-tunneling true
    supported-ip-version ipv4
    sync-with-active-directory true
}