From 4a5ca1013d84f9291890a15227a9c1297352d36a Mon Sep 17 00:00:00 2001

From: Alexey Gladkov <legion@altlinux.org>

Date: Thu, 13 Dec 2007 17:50:01 +0300

Subject: [PATCH] Fix gratuitous ARP

I confirm the bug on Linux. This problem happens, when

gratuitous_arp() appoints Sender IP value (arp[14])

in case of ARP request (enable_virtual==0).

----- Original Message -----

From: Marcus Goller <mgoller@...>

To: <list@...>

Subject: [ucarp] Gratuitous ARP

Date: Wednesday, March 21, 2007 - 10:13 am

Hi,

I am new to the list and just discovered ucarp recently and played around

with the latest snapshot version 1.3.

I am having some trouble with gratuitous ARP on Solaris, because when I

start up the backup daemon, it sends out an ARP message which gets picked up

by the network and the gateway sends traffic for the failover IP to the

backup client.

I narrowed down the issue to the line "gratuitous_arp(dev_desc_fd, 0);" in

the carp_set_state function for the BACKUP case. If I comment it out,

everything works as expected.

Has anybody else noticed this?

What exactly is the difference between enable_virtual = 0 and 1? From what I

have seen, the packets look identical.

Any help would be appreciated.

Thanks,

Marcus

http://kerneltrap.org/mailarchive/ucarp/2007/3/21/418982

Signed-off-by: Petya Kohts <kohts@yandex-team.ru>

Signed-off-by: Alexey Gladkov <legion@altlinux.org>

---

 ucarp/src/garp.c |    1 -

 1 files changed, 0 insertions(+), 1 deletions(-)

diff --git a/ucarp/src/garp.c b/ucarp/src/garp.c

index 4264641..e24ba63 100644

--- a/ucarp/src/garp.c

+++ b/ucarp/src/garp.c

@@ -32,7 +32,6 @@ int gratuitous_arp(const int dev_desc_fd, const int enable_virtual)

         memcpy(&arp[14], &vaddr.s_addr, (size_t) 4U);

     } else {

 	arp[7] = 0x01;

-	memcpy(&arp[14], &vaddr.s_addr, (size_t) 4U);

 	memset(&arp[18], 0xff, ETHER_ADDR_LEN);

 	memcpy(&arp[24], &vaddr.s_addr, (size_t) 4U);

     }

-- 

1.5.3.7.GIT