HP StorageWorks Scalable File Share Release Notes - Version 2.3

New and changed features in HP SFS Version 2.31–24
1. When two distinct IB fabrics are to be connected to the same SFS system, and if the servers are
configured with dual port HCAs or multiple HCAs, one distinct o2ib LNET (o2ib0, o2ib1) will be
associated to each IB interface.
2. To increase the per client node bandwidth, client nodes can distribute the SFS traffic across multiple IB
interfaces. This requires that multiple LNETs are defined. On the client side, one LNET will be
associated to each IB interface. On the SFS server side, the same LNETs will be associated to a single
IB physical interface. In such a case, there is no requirement to use multiple IB interfaces on the SFS
server node side, since the per SFS server bandwidth is limited by the storage. Instead, SFS server
nodes will be configured with one additional IB alias interface (for example, ib0:0 ib0:1 ...) per
additional LNET.
1. 8.2.5.1 Sec t io n 7.11.1a.1 LNE T se l e ct i on
Lustre chooses an LNET at connection establishment time:
• When a client node connects to a server node, the selection of the LNET is dictated by the LNET
module networks or ip2nets option.
• The LNET module network options are configured in the /etc/modprobre.conf (SFS servers) or
the /etc/modprobe.conf.lustre (SFS clients) file.
• The easiest option to use is the networks option. This is the one used by SFS automatically by default.
• The syntax of the networks option is: networks=network[,network[...]]
• The syntax of the network field is: nettype[N][(interfaces)]
• The syntax of the nettype field is one of the values: tcp gm elan vib o2ib
• The syntax of the interfaces field is: interface[,interface[...]]
• The syntax of the interface field for the o2ib nettype is: ibN[:M] and there can be
only one interface. If none is specified, the interface is implicitly ib0.
• Example: options lnet networks=o2ib0,tcp0(eth1)
• The more sophisticated ip2nets option allows to share the same LNET options on a set of servers, but
use distinct LNETs on each individual node, depending on the IP addresses of the node.
• The syntax of the ip2nets option is: ip2nets=net-match [#comment] [;net-match [#comment] [...]]
• The syntax of the net-match field is: network ip-range [ip-range ... ]
• The syntax of the ip-range field is: r-expr.r-expr.r-expr.r-expr
• The syntax of the r-expr field is: N | * | "["r-list"]"
• The syntax of the r-list field is: range [, range [...]]
• The syntax of the range field is: N [ - N [ / M ] ] with N a number from 0 to 255, and M an
integer step greater than 1.
• Example:
options lnet ip2nets="o2ib0(ib0) 172.22.0.[1-8]; o2ib1(ib0:0) 172.23.0.[2-8/2]"
where:
• o2ib0(ib0) would be configured on 72.22.0.[1-8]
• o2ib1(ib0:0) would be configured on 72.23.0.[2,4,6,8]
• When several possible LNETs are available, the system selects a single LNET as follows:
• Lustre selects the first LNET specified in the network option of the client node that is shared by
both the client and the HP SFS server it connects to.