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I am sticking with this problem for a couple of hours now and I am just not finding the right hint.

Dom0 is a Debian Squeeze.

I setup a Xen Server on a Dom0 using apt-get.

Dom0 has the ip Server is reachable and works fine. Installation is going thru without any issues.

I have an additional subnet /29. I set up the first ip of the subnet on the Dom0 to be my default gateway for my DomU's later on.

ip addr add dev eth0

ip is up and responses to pings, ssh connections etc.

sysctl.conf looks like this:






xend-config.sxp is set to:

(network-script network-route)

(vif-script vif-route)

Setting up a DomU is going thru as well. I am adding the ip address Unfortunately the ip address is not responding either outgoing/incoming.

Please note that these are not the real ip addresses.

Thanks for any help!

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up vote 1 down vote accepted

Just found the solution.

Debian supports in /etc/networks/interfaces an option called pointtopoint.

By adding this option with the gateway in the Dom0 and alls DomU's the routing works.

Be advised that on Dom0 you have to put the default gateway and on the DomU's the ip address of the ip address on the Dom0 in the same subnet.

Example: pointtopoint 10.x.x.1

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check iptables forward rules. must allow all traffic to vifX

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Didn't I activate this by putting net.ipv4.ip_forward=1 into the sysctl.conf and rebooting the server? Also I am not able to ping from Dom0 to DomU. – David Jul 26 '11 at 7:42
no. forwarding can be enabled, but all packets blocked by iptables. see iptables -L -n – arheops Jul 26 '11 at 12:14

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