I think you are right, and don't think I do have a route to the router. I typed arp -a and got ?incomplete address at Now if I could just find my startup scripts. I tried adding the router using route add -net (its a Cisco 2600 router, if that matters), but got an incomplete message. Should the router be addressed as a host or network? I appreciate your patience. Thanks. Jake >From: Clayton Weaver <cgweav@eskimo.com> >To: digimix@hotmail.com >Subject: eth0 card >Date: Thu, 29 Jun 2000 11:39:34 -0700 (PDT) > >Do you have a route to the router? > >Try > > route -n > >that will show you what the kernel thinks your current routing >table is in terms of host and network ip addresses. > >In your network startup scripts, you should have some > > route add ... > >commands. One should tell what device to access your own subnet >through (has a network address and netmask in the command), and >another should tell what device to access the default gateway >through (all non-local ip addresses go out this device), with >the ip address of the nearest router as the gateway ip address. > >If the kernel doesn't have a route to your local network number, >you won't get an arp reply back from the gateway router telling >your kernel what ethernet hardware address to associate with the >router's ip address. Requests for connection to that ip address >won't work without the ethernet hardware address, even though the router >necessarily has an ip address on your subnet. > >Lowest level step on ethernet is local ethernet hardware address >to ip number mapping. The ethernet packets search for where to connect >to by ethernet hardware address. A matching address keeps the packet >and non-matching MAC addresses on your local subnet ignore it. arp >is the protocol that establishes the local ethernet address to ip >number mapping, but it has to know what device to use to access the >local subnet, and the route command in your network bootup scripts >tells the kernel what device to send out arp requests for hardware >to ip number mappings for the local subnet on, as well as what device or >devices to send out ip packets in general on. > >The arp requests are broadcasts, received by every host that recognizes >the network number in the arp request as corresponding to its own subnet. >If the broadcast request is general, they all respond with their >ethernet hardware addresses. If the broadcast arp request is for >the MAC address of a specific host ip number on the subnet, then only that >host responds with it's ethernet hardware address (if there actually is a >host with that ip number on the subnet, i.e. if that host ip address is in >use and the host is up and running). > >Hth, > >Clayton Weaver ><mailto:cgweav@eskimo.com> >(Seattle) > >"Everybody's ignorant, just in different subjects." Will Rogers > > > ________________________________________________________________________ Get Your Private, Free E-mail from MSN Hotmail at http://www.hotmail.com - : send the line "unsubscribe linux-net" in the body of a message to majordomo@vger.rutgers.edu
