Common multi-site san network designs – HP StoreVirtual 4000 Storage User Manual
Page 11
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Assign servers to sites—Avoid high-latency connections by assigning application servers to
the site where the server is located. Application servers assigned to a site connect only to
storage systems in the same site as follows:
◦
Without MPIO—With servers set up in the CMC with the load balancing option, the
system sets up the iSCSI session only to storage systems assigned to the same site.
◦
With MPIO and the HP DSM—The system sets up iSCSI sessions only to storage systems
assigned to the same site.
◦
With MPIO and the Microsoft DSM—With servers set up in the CMC with the load
balancing option, the system sets up the iSCSI session only to storage systems assigned
to the same site.
•
Use the Failover Manager—Unless you have storage systems in three physical sites, use a
Failover Manager. Put the Failover Manager in the third site (physical or logical) located on
a network that is isolated from the other sites and has a different power connection.
Common Multi-Site SAN network designs
Based on the Multi-Site SAN configuration, there are many network designs that can be implemented
that solve the redundancy, high availability, and performance requirements for the Multi-Site SAN.
A few commonly used designs are:
•
Dual redundant links between the sites
•
Full-mesh triangular (three) redundant links between sites
•
Hub and spoke central network core with redundant links out to each site
•
Combination full-mesh core network with triangular (three) links between sites
Balancing the requirements for high availability during certain types of failures in the Multi-Site
SAN and the budget associated with the network infrastructure typically dictates the network
architecture a customer will choose to implement. Obviously, the most redundant network typically
will cost the most to implement. However, not implementing redundancy in the Multi-Site SAN
network significantly curtails the benefits of the Multi-Site SAN software.
network configurations and failure protection of each” (page 11)
shows the common Multi-Site
network configurations and the types of failures against which they provide protection.
Table 4 Common Multi-Site network configurations and failure protection of each
Storage system failure
protection
Network failure protection
Site failure protection
Network topology
Yes
Yes
Yes, with manual
intervention
Dual redundant links
between sites
Yes
Yes
Yes
Full-mesh triangular links
between sites
Yes
Yes, so long as the core
does not fail
Yes
Hub & spoke central core
Yes
Yes
Yes
Combo full-mesh core with
triangular links between sites
Sample recommended network configurations for Multi-Site SANs
Samples of common network configurations for the topologies described in
network configurations and failure protection of each” (page 11)
are illustrated in this section. The
clusters and sites can have many more storage systems than are depicted here. However, the
pictures are more focused on the network design.
Designing the network for the Multi-Site SAN
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