HP StoreAll Storage Network Best Practices Guide

Figure 1 Bond redundancy
Each bond interface has an associated mode property that controls the policy for routing network
traffic between the bonded interface and the aggregated physical interfaces. Linux bonding defines
six distinct modes that provide different degrees of load balancing and fault tolerance. See “BOND
modes” (page 69) for a description of the modes that can be employed in StoreAll platforms.
Each platform type supports specific modes:
• The StoreAll 97xx platform is configured to use mode 1 by default. HP recommends that the
bonds in the 97xx node configuration always use mode 1. The architecture of the c7000
enclosure, with the connections routed through the chassis midplane to the Virtual Connect
module, makes the use of modes other than 1 unnecessary.
• The StoreAll 93xx platform can use modes 4, 6, or 1, depending on the customer’s desired
configuration. Modes 4 and 6 allow for increased bandwidth between the discrete server and
the customer network through the enablement of LACP trunking and load balancing.
If the server has 10 Gb/s Ethernet links, mode 1 is recommended. The 10 Gb/s link should
provide sufficient bandwidth for a single server.
If the server has 1 Gb/s Ethernet links, modes 4, 6, or 1 can be used depending on the
customer node bandwidth needs. Linux networking tools such as ifconfig display the bonded
interface using a bond# device label. For example, the first bond created by StoreAll always
has the label bond0.
NOTE: Using mode 6 with VLAN Tagging is not permitted or supported.
StoreAll node failover
The StoreAll Storage platform provides high availability across the cluster by allowing the Fusion
Manager and File Clients to fail over between nodes in the cluster. Each node implements its portion
of the failover mechanism by associating Virtual Interfaces (VIFs) with the node’s bonded interfaces.
By carefully controlling which VIFs are enabled on a specific node, the migration of the active
Fusion Manager and File Client requests can be achieved in response to changing cluster health.
IP alias (VIF)
IP aliasing is an operating system capability that allows more than one IP address to be associated
with a single network interface. StoreAll terminology refers to these extra IP addresses as a Virtual
Interface or VIF.
Linux networking tools such as ifconfig display a VIF as an interface label followed by : and
a string that identifies the alias. For example, if bond0 is assigned a second IP address labeled
1, information about that IP address appears in a record labeled bond0:1.
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