MORE INFORMATION
You may be able to improve the connection reliability by not using direct
hosting from client to server. This forces NetBIOS to manage the session,
rather than making the redirector manage retransmissions. To turn direct
hosting off at the client, add the following parameter to the [network]
section of system.ini:
directhost=no
Note: Page 4-12 of the "Windows for Workgroups Resource Kit", Addendum for
Version 3.11 incorrectly states this parameter as 'directhosting'. This is
a documentation error.
Additionally, you must install the IPX/SPX Compatible Transport with
NetBIOS on the Windows for Workgroups client.
When you turn direct hosting off, large file read requests from the client
are requested in a read block raw SMB, and the data is transferred over the
NetBIOS session. The following trace shows at frame 20, the client
initiates a read block raw, and the data is returned by the server over the
NetBIOS session:
# DeltaT Src MAC Dst MAC Protocol Description
20 0.004 WFW Client NT server SMB C read block raw, FID = 0x800,
Read 0xfe00 at
21 0.147 NT server WFW Client NBIPX Session Data
22 0.001 NT server WFW Client NBIPX Session Data, Send Seq 0x0C,
Offset 0x5AC
23 0.002 WFW Client NT server NBIPX Session Data, Ack, Recv Seq
0x0D, 0x10 Bytes Received
24 0.002 NT server WFW Client NBIPX Session Data
25 0.002 NT server WFW Client NBIPX Session Data
26 0.001 NT server WFW Client NBIPX Session Data, Send Seq 0x0F,
Offset 0x16B0
27 0.002 WFW Client NT server NBIPX Session Data, Ack, Recv Seq
0x10, 0x13 Bytes Received
If direct hosting is on, then the redirector initiates a read block
multiplex, and the data is sent back in read block multiplex response SMBs,
directly over IPX. The following trace shows a read block multiplex coming
from the client at frame 19. Frames 20 through 29 show the server
responding with read block multiplex responses, and frame 30 is another
read block multiplex command from the client:
# DeltaT Src MAC Dst MAC Protocol Description
19 0.005 WFW Client NT server SMB C read block mpx, FID = 0x800,
Read 0x3750 at 0x00000000
20 0.003 NT server WFW Client SMB R read block mpx, Read 0x588 of
0x3750
21 0.006 NT server WFW Client SMB R read block mpx, Read 0x588 of
0x3750
22 0.001 NT server WFW Client SMB R read block mpx, Read 0x588 of
0x3750
23 0.002 NT server WFW Client SMB R read block mpx, Read 0x588 of
0x3750
24 0.002 NT server WFW Client SMB R read block mpx, Read 0x588 of
0x3750
25 0.001 NT server WFW Client SMB R read block mpx, Read 0x588 of
0x3750
26 0.001 NT server WFW Client SMB R read block mpx, Read 0x588 of
0x3750
27 0.002 NT server WFW Client SMB R read block mpx, Read 0x588 of
0x3750
28 0.001 NT server WFW Client SMB R read block mpx, Read 0x588 of
0x3750
29 0.001 NT server WFW Client SMB R read block mpx, Read 0x588 of
0x3750
30 0.004 WFW Client NT server SMB C read block mpx, FID = 0x800,
Read 0x3750 at 0x00003750
In this case, the redirector is responsible for requesting resends of lost
packets in either direction. This may be too much of a burden on the
Windows for Workgroups redirector which is running over an ODI driver. The
extra layer needed to map NDIS 3.0 protocols to an ODI NIC driver
(MSODISUP.386) may also contribute to the problem, as running direct
hosting over NDIS drivers does not seem to exhibit this problem.