Novell will beta test a Business Continuity Cluster
(BCC) product which enables up to four geographically distant
clusters, with Sans, to act as one load-balancing unit, which the
company calls a "cluster of clusters".
Richard Jones, Novell storage services product manager said,
"The geo distant cluster and San take over for the first cluster
that failed or was destroyed." In effect, the component clusters
form a single logical cluster.
BCC is flexible and can be used to have a live cluster and a hot
standby, or four life clusters, or a pair or two pairs of live
clusters backing each other up. Jones said that if disaster
happens, "the failover is a manual process. Customers can automate
it via scriptable interfaces if they desire".
The product to be tested offers iManager snap-ins, DirXML
drivers and storage array scripting control. Links between the
clusters can be ATM, fibre channel, IP or Sonet.
For the beta test the clusters must run Netware 6.5 SP1, which
supports both fibre channel and iSCSI Sans. A minimum of two
storage arrays must be capable of being controlled via command line
interface on the NetWare OS and have block level
replication/mirroring set up and running between them.
"BCC replicates the resource configuration information and
controls the host, San or storage array block-level replication.
The actual San replication is dependent upon the replication
capabilities offered in the San or host operating systems," said
Jones.
The actual replication and mirroring is carried out by server,
appliance or array-based products from Falconstor Software,
DataCore Software and others.
These products are already available for storage replication and
mirroring using other server operating systems such as Windows and
various Unix flavours. Appliance-based ones are beginning to appear
on intelligent fabric platforms like Brocade Communications
Systems' Fabric AP 7420.
EMC's SRDF is an example of array-based replication. Xiotech
offers multi-site storage clusters, needing no server-based
software to provide cluster-wide failover. This contrasts with
point-to-point replication or mirroring.
The Novell facility is up to four-way and covers clustered
servers and storage nodes. It is also controllable manually or can
be automated to suit customer's needs.
The BCC Services product is likely to be introduced in the
autumn.
Chris
Mellor writes for Techworld.com