Subject: amd64 + Linux + IP fragmentation = stall?
To: None <firstname.lastname@example.org>
From: Frank Kardel <email@example.com>
Date: 04/14/2004 22:43:00
i just set up an amd64 machine (ASUS K8V). Everything looked fine
until some Linux boxes attempted to use that machine as
The NFS-writes where stalled as the fragmented IP packets
where not answered. Statistics show that fragmented packets
are received and time out.
From netstat -s:
7228571 total packets received
0 bad header checksums
0 with size smaller than minimum
0 with data size < data length
0 with length > max ip packet size
0 with header length < data size
0 with data length < header length
0 with bad options
0 with incorrect version number
38361 fragments received
0 fragments dropped (dup or out of space)
0 fragments dropped (out of ipqent)
0 malformed fragments dropped
9287 fragments dropped after timeout
1326 packets reassembled ok
7188236 packets for this host
0 packets for unknown/unsupported protocol
1 packet forwarded (0 packets fast forwarded)
3286 packets not forwardable
1 redirect sent
0 packets no matching gif found
4988318 packets sent from this host
0 packets sent with fabricated ip header
0 output packets dropped due to no bufs, etc.
1 output packet discarded due to no route
1184 output datagrams fragmented
18272 fragments created
0 datagrams that can't be fragmented
0 datagrams with bad address in header
Successful reassembly can be seen when a NetBSD 1.6ZK is the client.
Linux does seem to trigger a reassembly inability in
NetBSD 2.0C (20040411) on amd64.
Any ideas ?