>>> On 4/19/2011 at 01:58 PM, "Eric K. Dickinson" <[email protected]> >>> wrote: > During the install and/or configuration of the 2nd, 3rd.... > interface everything works just fine. > > We can reach each adapter individually by IP address. > > Then we reboot. > > From that point we can see the traffic (tcpdump) arriving > at each interface but it never replies. > > What are we missing? What do you need to see?
I would check the contents of any file named rp_filter under /proc. Here's a list from my laptop: /proc/sys/net/ipv4/conf/all/rp_filter /proc/sys/net/ipv4/conf/default/rp_filter /proc/sys/net/ipv4/conf/lo/rp_filter /proc/sys/net/ipv4/conf/eth0/rp_filter /proc/sys/net/ipv4/conf/wlan0/rp_filter /proc/sys/net/ipv4/conf/pan0/rp_filter If they're set to 1, most likely your seeing "martian" messages in your system log. At that point, you have a choice: 1. Set them all to 0, using /etc/sysctl.conf. This is not preferred, since rp_filter provides some additional protection against spoofing. 2. Set up your routing properly and don't try to access any interface from any subnet. 3. Set up advanced routing policies to handle being able to respond to any subnet from any interface. Mark Post ---------------------------------------------------------------------- For LINUX-390 subscribe / signoff / archive access instructions, send email to [email protected] with the message: INFO LINUX-390 or visit http://www.marist.edu/htbin/wlvindex?LINUX-390 ---------------------------------------------------------------------- For more information on Linux on System z, visit http://wiki.linuxvm.org/
