diff --git a/confluent_server/confluent/discovery/protocols/pxe.py b/confluent_server/confluent/discovery/protocols/pxe.py
index a1c69b27..49e78d74 100644
--- a/confluent_server/confluent/discovery/protocols/pxe.py
+++ b/confluent_server/confluent/discovery/protocols/pxe.py
@@ -30,6 +30,7 @@ import ctypes.util
 import eventlet
 import eventlet.green.socket as socket
 import eventlet.green.select as select
+import netifaces
 import struct
 
 libc = ctypes.CDLL(ctypes.util.find_library('c'))
@@ -60,7 +61,7 @@ class sockaddr_ll(ctypes.Structure):
                 ('sll_hatype', ctypes.c_ushort),
                 ('sll_pkttype', ctypes.c_ubyte),
                 ('sll_halen', ctypes.c_ubyte),
-                ('sll_addr', ctypes.c_ubyte * 8)]
+                ('sll_addr', ctypes.c_ubyte * 20)]
 
 class iovec(ctypes.Structure):   # from uio.h
     _fields_ = [('iov_base', ctypes.c_void_p),
@@ -106,6 +107,22 @@ recvmsg.restype = ctypes.c_size_t
 
 pkttype = ctypes.c_char * 2048
 
+_idxtoname = libc.if_indextoname
+_idxtoname.argtypes = [ctypes.c_uint, ctypes.c_char_p]
+
+def idxtoname(idx):
+    name = (ctypes.c_char * 16)()
+    _idxtoname(idx, name)
+    return name.value.strip()
+
+_idxtobcast = {}
+def get_bcastaddr(idx):
+    if idx not in _idxtobcast:
+        bc = netifaces.ifaddresses(idxtoname(idx))[17][0]['broadcast']
+        bc = bytearray([int(x, 16) for x in bc.split(':')])
+        _idxtobcast[idx] = bc
+    return _idxtobcast[idx]
+
 
 IP_PKTINFO = 8
 
@@ -238,7 +255,8 @@ def proxydhcp():
             node = uuidmap[disco['uuid']]
         if not node:
             continue
-        myipn = myipbypeer.get(rqv[28:44].tobytes(), None)
+        hwlen = rq[2]
+        myipn = myipbypeer.get(rqv[28:28+hwlen].tobytes(), None)
         if not myipn:
             continue
         if opts.get(77, None) == b'iPXE':
@@ -435,7 +453,6 @@ def check_reply(node, info, packet, sock, cfg, reqview):
     repview[0:1] = b'\x02'
     repview[1:10] = reqview[1:10] # duplicate txid, hwlen, and others
     repview[10:11] = b'\x80'  # always set broadcast
-    hwaddr = reqview[28:44].tobytes()
     repview[28:44] = reqview[28:44]  # copy chaddr field
     if httpboot:
         proto = 'https' if insecuremode == 'never' else 'http'
@@ -480,7 +497,14 @@ def check_reply(node, info, packet, sock, cfg, reqview):
     else:
         repview[replen - 1:replen + 10] = b'\x3c\x09PXEClient'
         replen += 11
-    myipbypeer[repview[28:44].tobytes()] = myipn
+    hwlen = bytearray(reqview[2:3].tobytes())[0]
+    fulladdr = repview[28:28+hwlen].tobytes()
+    myipbypeer[fulladdr] = myipn
+    if hwlen == 8: # omnipath may present a mangled proxydhcp request later
+        shortaddr = bytearray(6)
+        shortaddr[0] = 2
+        shortaddr[1:] = fulladdr[3:]
+        myipbypeer[bytes(shortaddr)] = myipn
     if netmask:
         repview[replen - 1:replen + 1] = b'\x01\x04'
         repview[replen + 1:replen + 5] = netmask
@@ -501,26 +525,23 @@ def check_reply(node, info, packet, sock, cfg, reqview):
     datasum = ~datasum & 0xffff
     repview[26:28] = struct.pack('!H', datasum)
     if clipn:
-        staticassigns[hwaddr] = (clipn, repview[:replen + 28].tobytes())
-    elif hwaddr in staticassigns:
-        del staticassigns[hwaddr]
+        staticassigns[fulladdr] = (clipn, repview[:replen + 28].tobytes())
+    elif fulladdr in staticassigns:
+        del staticassigns[fulladdr]
     send_raw_packet(repview, replen + 28, reqview, info)
 
 def send_raw_packet(repview, replen, reqview, info):
+    ifidx = info['netinfo']['ifidx']
     tsock = socket.socket(socket.AF_PACKET, socket.SOCK_DGRAM,
                           socket.htons(0x800))
     targ = sockaddr_ll()
-    bcastaddr = bytearray(8)
-    hwlen = reqview[2]
-    if not isinstance(hwlen, int):
-        # python 2 is different than python 3...
-        hwlen = bytearray(hwlen)[0]
-    bcastaddr[:hwlen] = b'\xff' * hwlen
-    targ.sll_addr = (ctypes.c_ubyte * 8).from_buffer(bcastaddr)
+    bcastaddr = get_bcastaddr(ifidx)
+    hwlen = len(bcastaddr)
+    targ.sll_addr = (ctypes.c_ubyte * 20).from_buffer(bcastaddr)
     targ.sll_family = socket.AF_PACKET
     targ.sll_halen = hwlen
     targ.sll_protocol = socket.htons(0x800)
-    targ.sll_ifindex = info['netinfo']['ifidx']
+    targ.sll_ifindex = ifidx
     try:
         pkt = ctypes.byref((ctypes.c_char * (replen)).from_buffer(repview))
     except TypeError:
@@ -531,7 +552,8 @@ def send_raw_packet(repview, replen, reqview, info):
            ctypes.sizeof(targ))
 
 def ack_request(pkt, rq, info):
-    hwaddr = rq[28:44].tobytes()
+    hwlen = bytearray(rq[2:3].tobytes())[0]
+    hwaddr = rq[28:28+hwlen].tobytes()
     myipn = myipbypeer.get(hwaddr, None)
     if not myipn or pkt.get(54, None) != myipn:
         return
@@ -557,7 +579,7 @@ def consider_discover(info, packet, sock, cfg, reqview):
         check_reply(macmap[info['hwaddr']], info, packet, sock, cfg, reqview)
     elif info.get('uuid', None) in uuidmap:
         check_reply(uuidmap[info['uuid']], info, packet, sock, cfg, reqview)
-    elif packet[53] == b'\x03':
+    elif packet.get(53, None) == b'\x03':
         ack_request(packet, reqview, info)