Re: VRRP related

Re: VRRP related

[Matti Aarnio]

	More to the topic list for future questions of this type is
	linux-net@vger.kernel.org  (or  netdev@oss.sgi.com -- real
	DEVELOPMENT talk goes there), but do read on.

On Mon, Apr 16, 2001 at 03:06:44PM +0100, umam@delhi.tcs.co.in wrote:
> Hi,
> I am trying to put virtual mac address at the place of physical mac
> address , for that I have overwrite source hardware address with virtual
> address.Now when I try to ping to this machine with some other
> machine.It says request time out.While checking arp -a , gives me
> virtual mac address in ARP-Table instead of physical mac address.I want
> it should give response to ping  also.what I can do????

	You will, probably, need to run the VRRPed interface port
	in PROMISCUOUS mode, or use multicast address for the MAC-
	address, and process reception of that correctly.

	There probably are more problems at using the multicast
	MAC address, than turning the interface into promiscuous.
	(At least the Linux packet reception path treats MC MAC
	 destined packets specially.)

	ARP request gets in because it is MAC-level broadcast.
 
> thanks

/Matti Aarnio

Re: VRRP related

[Ion Badulescu]

On Mon, 16 Apr 2001 15:06:44 +0100, umam@delhi.tcs.co.in wrote:
> 
> Hi,
> I am trying to put virtual mac address at the place of physical mac
> address , for that I have overwrite source hardware address with virtual
> address.Now when I try to ping to this machine with some other
> machine.It says request time out.While checking arp -a , gives me
> virtual mac address in ARP-Table instead of physical mac address.I want
> it should give response to ping  also.what I can do????

1. Get a card that accepts non-multicast MAC addresses in its hardware
filter. eepro100, tulip, starfire will do. 3c59x won't (well newer cards
have the capability, but the driver doesn't support it).

2. Apply the attached patch and enable "Ethernet Virtual MAC support".

3. Tell the card about your VMAC using ipmaddr.

The patch slows down the fast receive patch, I know, but I don't see
a way around it. It's against 2.4.recent, I haven't looked at 2.2.

Ion

-- 
  It is better to keep your mouth shut and be thought a fool,
            than to open it and remove all doubt.
-----------------------
--- linux-2.4/net/ethernet/eth.c.old	Tue Nov 14 20:18:52 2000
+++ linux-2.4/net/ethernet/eth.c	Tue Nov 14 20:30:45 2000
@@ -203,8 +203,21 @@
 	 
 	else if(1 /*dev->flags&IFF_PROMISC*/)
 	{
-		if(memcmp(eth->h_dest,dev->dev_addr, ETH_ALEN))
+#ifdef CONFIG_NET_VMAC
+		if (memcmp(eth->h_dest,dev->dev_addr, ETH_ALEN)) {
+			struct dev_mc_list *mc_addr = dev->mc_list;
+			while (mc_addr) {
+				if (memcmp(mc_addr->dmi_addr, dev->dev_addr, ETH_ALEN))
+					goto loose_local;
+				mc_addr = mc_addr->next;
+			}
 			skb->pkt_type=PACKET_OTHERHOST;
+		loose_local:
+		}
+#else  /* not CONFIG_NET_VMAC */
+		if (memcmp(eth->h_dest,dev->dev_addr, ETH_ALEN))
+			skb->pkt_type=PACKET_OTHERHOST;
+#endif /* not CONFIG_NET_VMAC */
 	}
 	
 	if (ntohs(eth->h_proto) >= 1536)
--- linux-2.4/net/Config.in.old	Tue Nov 14 20:29:37 2000
+++ linux-2.4/net/Config.in	Tue Nov 14 20:30:31 2000
@@ -64,6 +64,7 @@
    tristate 'LAPB Data Link Driver (EXPERIMENTAL)' CONFIG_LAPB
    bool '802.2 LLC (EXPERIMENTAL)' CONFIG_LLC
    bool 'Frame Diverter (EXPERIMENTAL)' CONFIG_NET_DIVERT
+   bool 'Ethernet Virtual MAC support (EXPERIMENTAL)' CONFIG_NET_VMAC
 #   if [ "$CONFIG_LLC" = "y" ]; then
 #      bool '  Netbeui (EXPERIMENTAL)' CONFIG_NETBEUI
 #   fi

VRRP related

[umam]

Hi,
I am trying to put virtual mac address at the place of physical mac
address , for that I have overwrite source hardware address with virtual
address.Now when I try to ping to this machine with some other
machine.It says request time out.While checking arp -a , gives me
virtual mac address in ARP-Table instead of physical mac address.I want
it should give response to ping  also.what I can do????


thanks