arp problems with an avaya p334T switch

I want to connect 30 offices to Internet through a linux bering router.

Each office is connected to an avaya P334T switch. Each port of the switch is bound to its own VLAN. The linux router is attached to the port 1/47. This port is bount to all vlans.

Basically, it works. But sometimes connection to internet is impossible. It is even impossible to ping the router.

In that case, I see records like this one in the router's arp table :

192.168.5.2 (incomplete) eth2

..

The switch doesn't forward router's arp requests.

Any Idea.



--
Yann Aubert
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