Strange ARP problem

Hi!

Let me explain the simple architecture here. A linux machine with kernel 
2.6.11.7 (Debian Sarge) and e1000 driver. A Cisco Catalyst 6509 
configured with a trunk port this way:

interface GigabitEthernet4/13
 switchport
 switchport trunk native vlan 100
 switchport trunk allowed vlan 100,201
 switchport mode trunk

The linux machine has:

# cat /proc/net/vlan/config
VLAN Dev name    | VLAN ID
Name-Type: VLAN_NAME_TYPE_RAW_PLUS_VID_NO_PAD
eth0.201       | 201  | eth0

# ifconfig
eth0      Link encap:Ethernet  HWaddr 00:0B:DB:A9:0F:D1
          inet addr:172.19.1.11  Bcast:172.19.1.255  Mask:255.255.255.0
          inet6 addr: fe80::20b:dbff:fea9:fd1/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:49984 errors:0 dropped:0 overruns:0 frame:0
          TX packets:80330 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000
          RX bytes:4335305 (4.1 MiB)  TX bytes:110105417 (105.0 MiB)
          Base address:0xece0 Memory:fe8e0000-fe900000

eth0.201  Link encap:Ethernet  HWaddr 00:0B:DB:A9:0F:D1
          inet addr:172.22.1.2  Bcast:172.22.1.255  Mask:255.255.255.0
          inet6 addr: fe80::20b:dbff:fea9:fd1/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:255 errors:0 dropped:0 overruns:0 frame:0
          TX packets:361 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0
          RX bytes:22471 (21.9 KiB)  TX bytes:21547 (21.0 KiB)

If I put a test client on the VLAN100 the linux machine can ping the 
6509's VLAN100 interface and the test client.
Now, I can ping from the linux machine the VLAN201 interface of the 6509 
and (obviuosly) vice versa.
If I put a test client on the VLAN201 the test client _cannot_ resolve 
the MAC address of the linux machine while the linux machine has this 
resolved. If I do a tcpdump on the linux machine I see:

    * on the eth0.201 the ARP request from the client _and_ the reply
      from the linux machine to the client (this will never reach the
      client for an unknown reason)
    * on the eth0 the same (I think I've understood that this is normal)

putting static ARPs on the server/client solves the problem.
Can you give me some directions? Need some other information?

Thanks,
Normando

-- 
  Normando Marcolongo | Micso s.r.l.
   via Tiburtina, 318 | I-65128 Pescara, Italy
tel/fax (+39)08554105 | mob. (+39)3386296362

_______________________________________________
Vlan mailing list
[email protected]
http://www.lanforge.com/mailman/listinfo/vlan

begin:vcard
fn:Normando Marcolongo
n:Marcolongo;Normando
org:Micso s.r.l.
adr:;;via Tiburtina, 318;Pescara;;65128;Italy
email;internet:[email protected]
tel;work:+3908554105
tel;fax:+3908554105
tel;cell:+393386296362
x-mozilla-html:FALSE
url:http://www.micso.com
version:2.1
end:vcard