Linux bridge works partly

ls,

i have a problem with linux bridging. Out of 4 bridges, al bridging a tap
interface (for a virtual machine) with a pysical interface, 2 work fine, and 2 don't.

the ones that don't work:
- are sitecom LN-013 usb nic interfaces (1 of the working ones is another type of usb interface)
- can ping from tap to the bridge ip, and from bridge ip to tap
- can ping from (nic connected to) eth to the bridge ip, and from the bridge ip to nic connected to eth
- CANNOT ping from (nic connected to) eth to tap or vice versa.
- CAN get a ip over DHCP for a nic connected to eth, from the DHCP server on the tap (??)

2 other bridges on same machine, same config (except for the physical interface) work fine.

i've read some reports some drivers are not up to bridging. I tried swapping the non-working 'eth2' with the working 'eth3', which confirmed the problem is in the LS-013 USB interface.

- can anyone confirm the problem is in the LN-013 USB interfaces?
- is there any other way I can check wether the problem really is in the LN-013?

thanks for any help.

Robbert Wethmar
amsterdam
eml [email protected]