Date: Mon, 2 Nov 98 12:07:54 PST From: "D. Alex Neilson" <neilson@www.nugate.com> To: "Nick A. Fikouras" <nick@dcs.shef.ac.uk> Cc: "freebsd-questions@FreeBSD.ORG" <freebsd-questions@FreeBSD.ORG>, Alex Neilson <neilson@nugate.com> Subject: Re: Static Route, need help (was: Re: Static Route (Correction)) Message-ID: <CMM.0.90.4.910037274.neilson@www.nugate.com> In-Reply-To: Your message of Mon, 02 Nov 1998 12:07:22 %2B0000
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The main problem is that whenever a static route to a host is created, for no apparent reason, an ARP entry is created for the particular host indicating as its MAC address the address of the interface that was passed as argumen in the 'route add -host' command (!). What makes things even worse is that static links seem to create permanent arp entries. You can verify that by doing arp -a. In my case I had two machines that could not exchange traffic due to the folly arp table. All traffic transmitted by a node was destined at the link layer for itself!!!!. I checked with a network analyser. Oh yes! "tcpdump -e", shows this quite clearly: MAC source _and_ destination address the same! The way I've overcome this is, I've created I a file with all the proper arp entries and I load it up manually after booting has completed (check arp manual page for this). I know this not the most scientific way of doing it, if anybody has any suggestions I'm willing to change. I first tried replacing the bad arp entry with "arp -S" to no avail (it even nukes the route) . After much aggrevation, I made mini and micro network routes with netmasks like 0xfffffff8 or as small as 0xfffffffe (the latter actually seems to work, though I have't extensively tested it yet). I had previously played with "arp -f <file>" to no avail, but since you reported success, I tried again and was also "successful": first a myhost# route add -host 192.168.60.60 -interface vx0 to get Destination Gateway Flags Refs Use Netif 192.168.60.60 0:60:8:4:4:ed UHLS 0 0 vx0 then a myhost# arp -f arp.entries /* file arp.entries is just "192.168.60.60 08:00:20:73:87:89 pub\n" */ to get Destination Gateway Flags Refs Use Netif 192.168.60.60 0:60:8:4:4:ed UHLS 0 0 vx0 192.168.60.60/32 8:0:20:73:87:89 ULS2c 0 0 vx0 and we have arp entries myhost# arp -a myhost.domain.com (192.168.60.60) at 0:60:8:4:4:ed permanent myhost.domain.com (192.168.60.60) at 8:0:20:73:87:89 permanent published and then just "arp -d myhost" and the first arp entry goes away, leaving the desired second one, and things work the way we want. Were you able to avoid the deletion step? Alex Neilson To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-questions" in the body of the message
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