- bringing up a second network interface without an IP address will
prevent the kernel from being able to ARP for IP adddresses, effectively
hosing the IP stack until you bring *all* interfaces down at once.
It's due to a piece of code in devinet.c:ip_chk_addr which assumes
that an IP address of 0.0.0.0 is a magic flag indicating bootp address
aquisition or something.
To reproduce on a 2-interface machine:
ifconfig eth1 down
ifconfig eth1 up
Now try to ping a machine on your eth0 net and watch the 'arp called for
own address' messages. Better yet, sniff the wire and observe pings
going out with the ether address of eth0 as both their source and
destination addresses.
...............................................................................
Peter Desnoyers : Midnight Networks Inc. 200 Fifth Avenue Waltham MA 02154
pjd@midnight.com : Ph. 617/890-1001 Fax -0028 The Best in Network Software