DHCP Relay

Have a try with this config:

ltm virtual dhcp-tcp_vs {
    destination 172.31.0.151:any
    ip-protocol tcp
    mask 255.255.255.255
    pool dhcp-all
    profiles {
        tcp { }
    }
    source 0.0.0.0/0
    source-address-translation {
        type automap
    }
    translate-address enabled
    translate-port disabled
}
ltm virtual dhcp-udp_vs {
    destination 172.31.0.151:any
    ip-protocol udp
    mask 255.255.255.255
    pool dhcp-all
    profiles {
        udp { }
    }
    source 0.0.0.0/0
    source-address-translation {
        type automap
    }
    translate-address enabled
    translate-port disabled
}
ltm virtual dhcp-relay {
    destination 255.255.255.255:bootps
    dhcp-relay
    ip-protocol udp
    mask 255.255.255.255
    pool dhcp-any
    profiles {
        dhcpv4 { }
    }
    source 0.0.0.0/0
    translate-address enabled
    translate-port disabled
}
ltm pool dhcp-any {
    load-balancing-mode least-connections-member
    members {
        DC-11:any {
            address 10.2.0.11
            session monitor-enabled
            state up
        }
        DC-33:any {
            address 10.2.0.33
            session monitor-enabled
            state up
        }
        DC-22:any {
            address 10.2.0.22
            session monitor-enabled
            state up
        }
    }
    monitor gateway_icmp
}

Remember if using tmsh you can use the following command to import the config:

load sys config merge from-terminal

Then just paste the above config in and see how you go.

Cheers,