Graphcore IPU-POD128, Build And Test Manual, Page: 50 / 113

IPU-POD128 build and test guide
3.6.8 ToR switch to Dell server(s)
Using 2 of the 1.5m QSFP cables per server, connect the ToR switch to the server(s) as follows.
1) Feed the cables through the cut-outs in the side of the rack first ( Fig. 3.55 ).
Fig. 3.55: ToR switch to server cabling: feed cables through side cut-outs in rack
2) Connect the cables to the ToR switch and server as given in Table 3.8 :
Table 3.8: Server RNIC port mapping
Server RNIC port
ToR switch port Cables
Server # 4 RNIC port 1 ToR switch port # 1 QSFP 1.5m
Server # 4 RNIC port 2 ToR switch port # 2 QSFP 1.5m
Server # 3 RNIC port 1 ToR switch port # 3 QSFP 1.5m
Server # 3 RNIC port 2 ToR switch port # 4 QSFP 1.5m
Server # 2 RNIC port 1 ToR switch port # 5 QSFP 1.5m
Server # 2 RNIC port 2 ToR switch port # 6 QSFP 1.5m
Server # 1 RNIC port 1 ToR switch port # 7 QSFP 1.5m
Server # 1 RNIC port 2 ToR switch port # 8 QSFP 1.5m
ToR switch ports 8 and 7 connect to the bottom server (server 1). Therefore, if you are only using
1 server then only ports 8 and 7 of the ToR switch are used.
The final ToR switch to server cabling is shown in
Fig. 3.56 for a four server version.
Version: latest (2021-11-25) 46