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<div class="gmail_quote">On Wed, Aug 5, 2009 at 4:27 AM, Eli Cohen <span dir="ltr"><<a href="mailto:eli@dev.mellanox.co.il">eli@dev.mellanox.co.il</a>></span> wrote:<br>
<blockquote class="gmail_quote" style="PADDING-LEFT: 1ex; MARGIN: 0px 0px 0px 0.8ex; BORDER-LEFT: #ccc 1px solid">RDMA over Ethernet (RDMAoE) allows running the IB transport protocol using<br>Ethernet frames, enabling the deployment of IB semantics on lossless Ethernet<br>
fabrics. RDMAoE packets are standard Ethernet frames with an IEEE assigned<br>Ethertype, a GRH, unmodified IB transport headers and payload. IB subnet<br>management and SA services are not required for RDMAoE operation; Ethernet<br>
management practices are used instead. RDMAoE encodes IP addresses into its<br>GIDs and resolves MAC addresses using the host IP stack. For multicast GIDs,<br>standard IP to MAC mappings apply.<br><br>To support RDMAoE, a new transport protocol was added to the IB core. An RDMA<br>
device can have ports with different transports, which are identified by a port<br>transport attribute. The RDMA Verbs API is syntactically unmodified. When<br>referring to RDMAoE ports, Address handles are required to contain GIDs while<br>
LID fields are ignored. The Ethernet L2 information is subsequently obtained by<br>the vendor-specific driver (both in kernel- and user-space) while modifying QPs<br>to RTR and creating address handles. As there is no SA in RDMAoE, the CMA code<br>
is modified to fill the necessary path record attributes locally before sending<br>CM packets. Similarly, the CMA provides to the user the required address handle<br>attributes when processing SIDR requests and joining multicast groups.<br>
<br>In this patch set, an RDMAoE port is currently assigned a single GID, encoding<br>the IPv6 link-local address of the corresponding netdev; the CMA RDMAoE code<br>temporarily uses IPv6 link-local addresses as GIDs instead of the IP address<br>
provided by the user, thereby supporting any IP address. In addition, multicast<br>packets currently use the broadcast MAC.<br><br>To enable RDMAoE with the mlx4 driver stack, both the mlx4_en and mlx4_ib<br>drivers must be loaded, and the netdevice for the corresponding RDMAoE port<br>
must be running. Individual ports of a multi port HCA can be independently<br>configured as Ethernet (with support for RDMAoE) or IB, as is already the case.</blockquote>
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<div>How is port configuration (RDMAoE v. IB) accomplished ? Is it prior to boot time or dynamic ?</div>
<div> </div>
<div>-- Hal</div>
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<div><snip...></div></div>