From owner-freebsd-questions Tue Jun 20 9:34:59 2000 Delivered-To: freebsd-questions@freebsd.org Received: from pobox.niagara.edu (pobox.niagara.edu [207.10.159.3]) by hub.freebsd.org (Postfix) with ESMTP id B078837C067 for ; Tue, 20 Jun 2000 09:34:49 -0700 (PDT) (envelope-from rpk@niagara.edu) Received: by POBOX with Internet Mail Service (5.5.2650.21) id ; Tue, 20 Jun 2000 12:31:19 -0400 Message-ID: <0D274047A242D2119B1D006008C19DD67B85A6@POBOX> From: "Richard P. Kernin" To: "'freebsd-questions@FreeBSD.ORG'" Cc: "Richard P. Kernin" Subject: Network Interface Grabbing Random IP Addresses Date: Tue, 20 Jun 2000 12:31:18 -0400 MIME-Version: 1.0 X-Mailer: Internet Mail Service (5.5.2650.21) Content-Type: text/plain; charset="iso-8859-1" Sender: owner-freebsd-questions@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG Hi, We've been experiencing some strange behavior on one of our FreeBSD boxes for the last few months. Originally the system was running v2.2.x with an Intel EtherExpress NIC (fxp0), but when we started experiencing problems we upgraded to the current revision of the time v3.4 and upgraded the hardware moving to a 3Com XL NIC (xl0) to be consistent with what we are using in other areas. What is happening is that the system appears to be grabbing random IP addresses, aliases, in addition to it's statically assigned IP address, then dropping them after a time. The arp tables reflect the aliases, and quickly fill up, all for the same MAC address. ? (xxx.xx.xxx.24) at 0:50:4:3:xx:xx permanent [ethernet] ? (xxx.xx.xxx.76) at 0:50:4:3:xx:xx permanent [ethernet] ? (xxx.xx.xxx.80) at 0:50:4:3:xx:xx permanent [ethernet] ? (xxx.xx.xxx.89) at 0:50:4:3:xx:xx permanent [ethernet] ? (xxx.xx.xxx.94) at 0:50:4:3:xx:xx permanent [ethernet] [etc] xl0: flags=8843 mtu 1500 inet xxx.xx.xxx.3 netmask 0xffffff00 broadcast xxx.xx.xxx.255 inet xxx.xx.xxx.214 netmask 0xffffffff broadcast xxx.xx.xxx.214 ether 00:50:04:03:xx:xx media: 100baseTX supported media: autoselect 100baseTX 100baseTX 100baseTX 10baseT/UTP 10baseT/UTP 10baseT/UTP The subnet that this machine is on has it's IP addresses assigned via DHCP, except for a block set aside for static assignment (of which this server is statically assigned). We are using ISC DHCP server running on FreeBSD, on another server v3.4 that is functioning properly. As a result of this machine grabbing random IP addresses/aliases it eventually "bumps" into workstations that are legitimately assigned the IP addresses (not a good thing). I've upgraded the operating system, replaced the hardware, used the generic kernel, as well as the compiled kernel we use specifically for that system, all to no avail. We've successfully used FreeBSD (and the originally 386BSD! ;-) for 5+ years without problems, so this is the first time we've been stumped. The machine is running the Apache webserver, but is not doing any virtual hosting, and we don't do IP aliasing on any of our systems (am familar with how to do this, as we did it years ago on now defunct systems for a project). Any suggestions or insight into what might be causing this behavior is greatly appreciated. Thank you. -rpk ---------- Richard P. Kernin Assistant Director, Information Technology Niagara University, NY 14109-2019 Internet: rpk@niagara.edu To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-questions" in the body of the message