Network FUBAR
I'm trying to move my server to another system without reinstalling. The old
system is a cheap whitebox running generic components. The new system is an
IBM eserver 325. I did a deep copy of the entire old system harddrive and
put it in the new server, booted from a rescue CD, installed grub on the MBR,
then rebooted the new system. Everything seems to be working fine except for
networking, which is deeply and perplexingly hosed.
The current symptoms are that I have no connectivity. I can bring up the
interface and it shows connected. I can ping the IP assigned to the
interface from the computer. The input and output counters increment when I
show the interface. But I can't ping another computer on the same subnet
plugged into the same switch. I get "destination host unreachable" back from
the IP assigned to the interface.
The relevant subnet is in the server's routing table, as is a default route.
I've even tried adding static routers pointing directly to the IP of the
other machines.
The computer is plugged into a 16 port switch module installed in a Cisco
router. Looking at the interface from the router, it shows connected and the
counters on the interface increment as well. The IP address for the server
appears in the router's ARP table with a hardware address of "incomplete" and
blank under the associated interface. I have multiple devices plugged into
the switch, and I've swapped the cables and the switchports around. The
other devices have no connectivity issues, and this server has no
connectivity, regardless of where it's connected. That seems to pretty much
eliminate an external layer 1 issue or something silly like being in the
wrong VLAN. (For thoroughness, let me add that there are no access lists or
other configs on the router that could even conceivably interfere with the
server's connectivity.)
The server has two onboard Broadcom NetXtreme NICs, which both behave
identically. They may very well share common hardware, so I installed a
Netgear RTL81695 based NIC. Completely different hardware, using a
completely different driver. It behaves identically to the onboard NICs.
That seems to rule out a hardware issue, but I'm at a loss as to what
software issue could cause these symptoms either.
Anyone have any ideas before I wipe the hard drive and start from scratch?
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