NOVELL TECHNICAL INFORMATION DOCUMENT

TITLE:  NetWare Cluster Services v.1.01 Update
TID #:  2956097
README FOR:  nwcsupd1.exe

NOVELL PRODUCTS and VERSIONS:
NetWare 5
NetWare Cluster Services for NW5

ABSTRACT:

NetWare Cluster Services v.1.01 for NetWare 5 - Two-node Cluster Tiebreaker
update.



-----------------------------------------------------------------
DISCLAIMER
THE ORIGIN OF THIS INFORMATION MAY BE INTERNAL OR EXTERNAL TO 
NOVELL.  NOVELL MAKES ALL REASONABLE EFFORTS TO VERIFY THIS 
INFORMATION.  HOWEVER, THE INFORMATION PROVIDED IN THIS DOCUMENT 
IS FOR YOUR INFORMATION ONLY.  NOVELL MAKES NO EXPLICIT OR IMPLIED 
CLAIMS TO THE VALIDITY OF THIS INFORMATION.
-----------------------------------------------------------------


INSTALLATION INSTRUCTIONS:

1. NetWare Cluster Services v.1.01 for NetWare 5 must be installed.  If you
have NetWare Cluster Services v.1.00 for NetWare 5, you can upgrade it to
v.1.01 by installing NetWare Cluster Services v.1.0 Support Pack 1.

2. Shut down the cluster by typing CLUSTER DOWN on one cluster node and then
typing ULDNCS on all cluster nodes.

3. Install the patch by copying GIPC.NLM and SBD.NLM file to the SYS:SYSTEM
directory on each server in the cluster.

4.  Restart the cluster by typing LDNCS on all cluster nodes.


Notes

The patch consists of two NLMs:  SBD.NLM and GIPC.NLM.  The build number for
these two NLMs is 000316.  This can be displayed by entering the command M <NLM
Name> at the server console.

For example:  M sbd.nlm


ISSUE: 

This patch improves the behavior of the split brain detection tie breaker
algorithm in two-node clusters. 

In a two-node split brain condition, one cluster node wins the tie breaker, the
other node loses, and the losing node restarts. Prior to this patch, the node
that won was always the cluster master node. Even if the master node had lost
its Ethernet connection to the other node, it would survive while the other
node  restarted. This resulted in neither node maintaining client/server LAN
connectivity, and it effectively shut down the entire cluster for client
access.

With this corrective patch, the node that loses the two-node split brain tie
breaker and restarts is always the node that lost its LAN link (if this can be
determined).  This patch supports single NIC solutions only. Redundant NICs are
not supported; if *both* paths of a redundant NIC based LAN are lost, the split
brain tie breaker behavior is the same as before. The cluster master node will
win the tie breaker.

Customers now have the choice of deploying a dual NIC solution for LAN hardware
redundancy, or they may use this patch to ensure the node with good LAN
connectivity always survives the two-node split brain tie breaker in single NIC
(non-redundant) LAN configurations.


Self-Extracting File Name: nwcsupd1.exe

Files Included          Size         Date          Time
..\
  NWCSUPD1.TXT   (This file)
..\NWCSUPD1\
      GIPC.NLM        171288    3-16-2000    3:42:34 pm
       SBD.NLM         21053    3-16-2000    3:33:28 pm



-----------------------------------------------------------------
Any trademarks referenced in this document are the property of their respective
owners.  Consult your product manuals for complete trademark information.
-----------------------------------------------------------------