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Conference decwet::winnt-clusters

Title:WinNT-Clusters
Notice:Info directories moved to DECWET::SHARE1$:[NT_CLSTR]
Moderator:DECWET::CAPPELLOF
Created:Thu Oct 19 1995
Last Modified:Fri Jun 06 1997
Last Successful Update:Fri Jun 06 1997
Number of topics:863
Total number of notes:3478

770.0. "What can be included in the "Failover" ?" by NNTPD::"zofka@mail.dec.com" (Milan ZOFKA) Fri Apr 25 1997 09:15

(Sorry for twice the query, the WEB interface send the note if you press
return after the subject...)

Hello,

I'm currently configuring a nice cluster config for a big customer but I still
have some questions and it's hard to find replies...

The config will be a "Enterprise NT Server" for more than 550 NT workstation
Clients. Based on Digital Clusters on dual 4100 servers, bi-processor and over
100 Gb storage. 4 or 5 Infoservers and the NT client Kit. 100 Base TX network.

The questions are:

Will dual 4100 with StorageWorks be supported on Wolfpack in the future?

The customer need FPNW and this service MUST be present on the cluster. It
seem that FPNW is not Cluster Aware, am I right? Does it mean that if a server
crash, the clients have to reconnect manually to the other server? (well, need
to modify the login script to access the other server of the cluster, the
disks being automatically remounted on the other node)

Is it possible to connect both servers, using 100 base TX Fast Ethernet
boards, each server being connected on a different Cabletron Switch line (not
on the same LAN but each on a different "extended LAN"?

Is it possible to provide Shares comming from Infoserver on the Cluster Alias
(should be possible because the disks are available all the time on the
Network using the LAST protocol)?

The dual 4100 config will run File & Print service but also applications of a
3 tiered Client-Server model (SAP mostly, application level only, DB is on
Oracle on a D-UNIX Cluster), Intranet SW (IIS and associated parts) and
Exchange Server. How does Exchange interoperate with all the others SW? I've
seen that the recommendations are to provide the Exchange service on a
dedicated server due to "problems"... The idea of the cluster is to provide
high availability and investment protection... The customer would like to run
a maximum of services on one node and File and Print on the other. What may
happend if one node crash and the other start the services of the other one?
Would it work correctly (maybe a previsible performance reduction) ? Maybe
Exchange is not Cluster Aware (no idea) or may break the F&P service.. Any
idea?

Thank you in advance for any info you may give me

Milan ZOFKA
Digital NSIS Geneva
MCSE & UNIX Ambassador
zofka@mail.dec.com
DTN: 821 5937
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770.1Some answers for Wolfpack capabilitiesSUTRA::16.36.3.236::BatsSpeeding, speeding, I'm always speedingMon Apr 28 1997 11:2152

	Dual 4100 will be supported on day one by Wolfpack.
	
	FPNW does not work in a cluster context.
	Not for Digital NT Clusters nor for Microsoft Wolfpack.
	This might change in a future version of Wolfpack, but I've
	not seen any references to it by MS.
	So you would need to use other methods to try get some sort of
	automatic failover to work, like indeed using login scripts).

	What is extended LAN here? It's a switch no?
	Wolfpack uses normal NetBIOS over TCP/IP to the announcing of
	"services". Or clusternames. In contrary to Digital NT Clusters
	today, they will be propagated by WINS servers.
	So if they can access remote NetBIOS names\servers\domains with
	this setup, using TCP/IP, then this should work for Wolfpack
	clusters as well.

	I'm guite sure you can not reshare InfoServer CD-ROMs.
	I thought that these were first personal shares, so not available
	to the "system" context, but to the user logged in.
	(Might be wrong here)
	However, unless these CD-ROM connections to the server, look like
	"disks", Wolfpack does not know what to do with them.
	Wolfpack can only make resources available it knows.
	(Just like Digital NT Clusters)
	If these CD-ROMs look like real disks, then there's no problem
	provided there are available to the system and at the time
	the Wolfpack drivers come up.(Cludisk.sys it's called I believe)
	If they look like real CD-ROMs then no go.
	Wolfpack does not support CD-ROMs. (Nor does Digital NT Clusters)
	This support should be added somewhere in a future release of 
	Wolfpack.

	For now Exchange does not work in a cluster context.
	(It has hardcoded in the EDB, or private/public store, the
	 domainname\systemname of the original system it was installed on,
	 and refuses to function if brought on-line on anything else)
	If I understood things correctly, there will be a Service Pack
	available to Exchange to will change this, allowing Exchange to
	failover to another cluster member.
	This Service Pack should be available when Wolfpack comes out.
	
	There's no problem when one system would get the other services
	that orginally were on the other server. It might be that 
	performance would be that bad, that you need to tailor this though.


	Pjotrr


770.2I found a bit more info but still have questionsNNTPD::"zofka@mail.dec.com"Milan ZOFKATue Apr 29 1997 13:1946
Thank you for all your inputs. BTW, I found some more info and have more
details for my qustions.

First thing. It seem that D-Clusters are not able to provide Printservice
failover due to the way the spooler works! It seem that MS is working on this
for the first release of WolfPack, am I right?

For FPNW the idea would be to install the first server with Netware name
NW_SVC then stop the service. Install the same with the same name on the
second server, then stop the server.

Now: Start the file service on one of the cluster member, then start the FPNW
service on the SAME node (well, the disks are mounted on the node how serve
the files). In case of trouble, stop BOTH services (normal file service &
FPNW) and restart them on the other one. Maybe the clients will have to
reconnect to the file server (IPX/SPX reason) and it will not be transparent
but still available as a TCP service would do (vs UDP).

The word "extendedLAN" was in quotes. I mean that the switch does
automatically some kind of bridging. It's just a conceptual question... You
know, with SCSI, if you have one disk how has a bad revision level, everything
may crash due to a 1 micro second delay in a disk, my question is exactly the
same but on a 100 base TX Ethernet line... It's not a "direct" connexion, but
some kind of bridged one... I'm quite sure that if the node is on the same
subnet (10.x.y.z BTW), it will work. But sometimes you find strange things in
the registry, like mac addresses!!! (probably the reason for a same subnet, a
router gives his mac adress, not the other node's one).

Infoservers: sorry for the engineering but it's not interesting in my case. I
tried the client kit and have seen that each CD rom has to be mounted on a
drive letter. Can you explain me how to mount 100 GB disks in several volumes,
A: B: are floppy, C: D: are system disks, the last ones (well, around 15) are
not enough for my 30 CDs... And i don't want to add a new protocol and a new
service on the 550 Workstations. Some manufacturers propose a Tree of CD on
their towers. Good, you just mount the tree and share every disks so clients
can access the CDs through UNC. But too bad, only a Intel version exist!

Yes, I learned that Exchange is not able to be moved on the other cluster node
due to registry entries/restriction. I always think that MS has still a lot to
learn about "enterprise computing". It's not desktop computing! MS is great
for the individual.

Any input are welcome

Milan
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