Conference netcad::hub_mgnt

3351.0. "Alphaserver 1000 4/200, FDDI, DEFEA, DEChub, Pathworks Slow" by GIDDAY::STANISLAUS () Tue Mar 12 1996 01:06

Posted in Alphanotes, Alphastation, FDDI, HUB, PWDOSWINV5, VMSNOTES conferences:
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Problem:
--------

	I was asked to investigate a possible network problem causing very slow
response on Pathworks Clients. The response is sometimes very bad - taking
upto 4 or 5 minutes for example to upen up a Microsoft-WORD document on the 
server and sometimes tolerable but still bad - taking upto 40 or 50 seconds 
to open a document. The problem has become worse over the last 6 months. This
was all installed in Sept 1995.

	The servers are used by a College and sometimes it could take upto 15 
minutes to open up a Student's Enrolment Screen on a client.

	From the investigations I have done (I work in the networks area), I do
not agree with the initial diagnosis by others that this is a situation of a 
broken DEChub 900 or broken FDDI units in the hub.

	I somehow think the problem is one of resources on the servers or 
something else wrong with Pathworks and or the Servers. I need some tips on 
getting started in the right direction to troubleshoot this problem, because 
I am neither a VMS guru nor a Pathworks specialist.

	I can't see any excessive errors on the Ethernet or FDDI or excessive 
collisions on the Ethernet.

System Configuration:
---------------------

	Alphaserver 1000 4/200 - 3 systems with a DEFEA (FDDI-UTP) adapter
in each system and a lot of Raid Storageworks Disks on each system - some of
which are shadowed across the systems. The Raid Disks are driven by PCI
based RAID controllers.

	VMS ver 6.2 and Pathworks version 5 and UCX (not sure of version).

Network Configuration:
----------------------
	
	
	One DEChub 900 with a DC900MX whose ports 1,2,3 are connected to the
above 3 Alphaservers. This DC900MX is in slot 6. 

	On the backplane an FDDI dual ring is created. To this ring the above
DC900MX and a DECswitch 900EF is attaced. This DS900EF is in slot 8.

	5 x Ethernet IMBs are created on this DEChub 900. Say E1,E2,E3,E4,E5.

	A DECrepeater 900FP is in slot 5 with ports 1 and 2 in Group 1, ports 
3 and 4 in Group 2, ports 5 and 6 in Group 3 and ports 7 and 8 in Group 4.
Ports 9,10,11 and 12 are unused. Thinwire stub is dropping down from the
DR900FP but not connected to the thinwire segment. Thinwire is associated with
ports 11 and 12, but as I said it is not connected from the DR900FP.

	Group 1 of the DR900FP is connected to IMB E1, Group 2 to IMB E2, 
Group 3 to IMB E3 and Group 4 to IMB E4.
	
	DR90TS in slots 1,2,3 are connected to IMB E5.

	Slot 4 contains a DECbrouter 90 connecting to a WAN.

	Except for DR900FP (still running 1.1 F/W) all other DH900 modules
run the latest F/W.

	There are totally 16 DEChub 90 backplanes on this site.

	The 8 ports of the DR900FP are connected to 8 pairs (i.e. 16 units) of
DEChub90 entering the DEChub 90 via a DECbridge 90FL. So, for example port 1
of DR900FP above goes to a DECbridge 90FL installed in a remote DEChub 90 which
is daisy chained to a 2nd DEChub 90. Similarly for port 2 of DR900FP, port 3,
etc. So that explains the 16 DEChub 90s.

	Each 16 slot DH90 has about 10 or 12 DR90TS, one DS90M, a DECbridge
90FL and some DH90s contain a DECagent 90. 

Client Configurations:
----------------------

	Pathworks for DOS clients run either Windows 95 or Windows for Work-
Group 3.11 There are about 240 that use Netbui and about 40 that use TCP/IP.
So the usage is mostlty Netbui.

	On this network there are also MAC clients and separate MAC servers
that are not facing any problem, but they are all on Ethernet. No connection
to FDDI. The MAC clients and MAC servers are connected via the DR90TS (x3)
in the DH900.


	Any ideas about the slow response or any tips on a starting point to
look at the server/cluster/pathworks configurations, etc.


	The clients are all Digital PCs of various models and the Ethernet
cards are all Digitals of various models. They all see the problem.

Alphonse

    
    2 things:
    
    Do you have Performance data collector and performance advisor on the
    Alpha systems?
    
    Do you have a DECpacketprobe 90?

    Check the UCX patches in the UCX notes conference ... I have had DEC
    UCX cause some weird problems in the past 
    
    
    
    -charlie