My setup is as following: Using kvm and tap-interfaces I have two vms running. The two tap-interfaces are connected via a bridge. On tap0 I have a DHCP-server running, on tap1 I executed a "dhclient". Using tcpdump I got to know that tap1 sends a request, which is received by the server. The server replies. I can see the reply on the bridge interface, however the reply never gets to the client.
Also if I assign an IP to the client manually, I'm not able to ping in neither direction (server-client, client-server)
I have also tried setting all to 0 in /proc/sys/net/bridge/
Any help would be appreciated.