Date: Mon, 03 Aug 2009 12:39:53 -0700 From: Xin LI <delphij@delphij.net> To: Jack F Vogel <jfv@FreeBSD.ORG> Cc: freebsd-net@freebsd.org Subject: em(4): sending ARP regardless of NOARP flag Message-ID: <4A773D09.3030404@delphij.net>
next in thread | raw e-mail | index | archive | help
-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1
Hi, Jack,
I have observed that, even if -arp is specified when adding an IP
address to the em(4) interface, an ARP request is still being sent.
Here is a tcpdump from my network environment:
11:15:01.370256 00:13:72:66:b5:d7 > ff:ff:ff:ff:ff:ff, ethertype ARP
(0x0806), length 60: Request who-has *.*.152.120 tell *.*.152.120, length 46
11:15:01.370270 00:15:17:92:39:0e > 00:13:72:66:b5:d7, ethertype ARP
(0x0806), length 42: Reply *.*.152.120 is-at 00:00:5e:00:01:07, length 28
(The first ARP request was sent from a Dell branded Intel 82541EI based
NIC, the latter is from a cheaper server that is part of CARP
configuration which is unrelated to the problem in response to the ARP
request)
I was originally under the impression that there is some bug in our ARP
code but with a bce(4) card, the problem does not exist. After a glance
at e1000 driver code, it looks like that the e1000 NIC has a feature of
hardware interception of ARP, can this be somehow connected? The
hardware in question is 82541EI based:
em1@pci0:7:8:0: class=0x020000 card=0x016d1028 chip=0x10768086 rev=0x05
hdr=0x00
vendor = 'Intel Corporation'
device = '82541EI Gigabit Ethernet Controller'
class = network
subclass = ethernet
Thanks in advance!
Cheers,
- --
Xin LI <delphij@delphij.net> http://www.delphij.net/
FreeBSD - The Power to Serve!
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v2.0.12 (FreeBSD)
iEYEARECAAYFAkp3PQkACgkQi+vbBBjt66A2CQCgt+8prSPRDKdOb61gdfj1zpcF
q28An1/UXuo0bcEi4nwlUpYuqD8hR5Lo
=56SA
-----END PGP SIGNATURE-----
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?4A773D09.3030404>