We have seen drops from 2.x Gb/hr to 700 Mb/hr on a dedicated Token Ring,
but ours is on an AS/400 using TCP/IP. Our problem was declared "system
wide" on the AS/400 by the Rochester TCP/IP people.
First, confirm w/ ADSM support that your communications settings in DSM.OPT
and on the ADSM server are max-ed out. Then:
Try a protocol analzer trace, and see if the Novell box is constantly ACKing
with a large window size, followed by your ADSM server responding with a
fairly small transmission. In our case, Novell sends several (2-4) packets
advertising a 25K - 32K window, and the AS/400 dribbles down 2K of restore
data. These types of transactions cover far > than 95% of the traffic
during our restores.
Beware of your server's support using the trace data and focussing on an
occasional (2 - 5 times per hour) transaction where the Novell machine
fails to respond for 1 - 3 seconds (reference PMR 94272) We traced this to
the RAID arrays flushing, and found it perfectly acceptable. Support wanted
us to open a call with Novell, to the exclusion of nailing down the reasons
for the AS/400 failing to send data. When we repeatedly pointed out that 15
seconds per hour of Novell silence was insigificant compared to the AS/400's
failure to keep the Novell machine saturated with data, we got the "AS/400
system wide" diagnosis.
If you can get a handle on your traffic, and it fits the description I've
given above, I'd be most interested in hearing from you directly, since
you're running AIX. It might not be AS/400 "system wide", and we want to
communicate that back to our contacts.
Steve Kuhn, Network Manager
AEGIS Insurance Services, Inc.
Jersey City, NJ 07302
201.521.4565 (v)
kuhns AT aegislimited DOT com
----------
From: "ADSM: Dist Stor Manager"
To: ADSM-L
Cc: AEGISLAN/AEGIS/KUHNS; AEGISLAN/AEGIS/MUGNOLL; AEGISLAN/AEGIS/kantorr
Subject: Novell restoreproblems
Date: Wednesday, April 01, 1998 9:54AM
MCI Mail date/time: Tue Mar 31, 1998 1:00 pm EST
Source date/time: Tue, 31 Mar 1998 13:41:17 +0100
-------------------
Hello,
We are currently trying to restore a novell box of approx 2.5g
Latest client, and AIX ADSM server at latest level.
the first 400 mb goes through in about an hour, after that the rate
slows to 3 - 12 mb an hour!.
We have traces running for it for IBM but I just wondered if anyone had
come across anything similar.
One symptom we are looking at seems to be that the Novell client will
send a packet across the network to the adsm box, but then the ADSM box
sits and waits for a minuite or so before sending anything back.
Thanks,
Matthew Warrn.
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