Load Balancing with Infiniband

Eric Barton wrote up something a year and a half ago (Bryon). Sent email to Sheila 10/6.

From OM Chapter 7

There is one OSS with two InfiniBand HCAs. Lustre clients have only one InfiniBand HCA using native Lustre drivers of o2ibind. Load balancing is done on both HCAs on the OSS with the help of LNET.

Options under modprobe.conf are used to specify the networks available to a node. You have the choice of two different options – the networks option, which explicitly lists the networks available and the ip2nets option, which provides a listmatching lookup. Only one option can be used at any one time. The order of LNET lines in modprobe.conf is important when configuring multi-homed servers. If a server node can be reached using more than one network, the first network specified in modprobe.conf will be used.

7.3.1 Modprobe.conf Lustre users have options available on following networks. ■ Dual HCA OSS server options lnet ip2nets= "o2ib0(ib0),o2ib1(ib1) 192.168.10.1.[101-102] ■ Client with the odd IP address options lnet ip2nets=o2ib0(ib0) 192.168.10.[103-253/2] ■ Client with the even IP address options lnet ip2nets=o2ib1(ib0) 192.168.10.[102-254/2]

7.3.2 Start servers

To start the MGS and MDT server, run: modprobe lnet To start MGS and MDT, run: $ mkfs.lustre --fsname lustre --mdt --mgs /dev/sda $ mkdir -p /mnt/test/mdt $ mount -t lustre /dev/sda /mnt/test/mdt $ mount -t lustre mgs@o2ib0:/lustre /mnt/mdt

To start the OSS, run: $ mkfs.lustre --fsname lustre --ost --mgsnode=mds@o2ib0 /dev/sda $ mkdir -p /mnt/test/mdt $ mount -t lustre /dev/sda /mnt/test/ost $ mount -t lustre mgs@o2ib0:/lustre /mnt/ost

7.3.3 Start clients

For the IB client, run: mount -t lustre 192.168.10.101@o2ib0,192.168.10.102@o2ib1:/mds/client /mnt/lustre

For more information about othe LNET options, see 31.2.1 LNET OPtions in the Lustre Operations Manual

For information about "How to build and configure Infiniband support for Lustre" the topic by thi =s nathe Lustre Knowledge Base in Appendix B in the Lustre Operations Manual.