Node Boot Mechanism

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Configure BIOS

Disable Hyper Threading

Hyper Threading is a very cheap trick to simulate dual CPUs. All it does is create a second entry point into the pipeline which should reduce bubbles in the pipeline but it can be detrimental for some mathematical functions of which we do many. Turn it off in the BIOS if you can.

Disable C-States

If the computer is to do significant computation (e.g. cluster node, lustre server, etc) then disable both C1E and C-State in the BIOS. On Dell Poweredge servers, set the Performance (OS) option in the BIOS.

Set Boot Order

The nodes boot using the Pre Execution Environment (PXE) protocol to boot. To do this the BIOS settings on the nodes must be changed from the default. Set the boot device order to

1. Optical (CD/DVD)
2. NIC
3. Hard drive The NIC is configured to use PXE by default.

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Configure DHCP

The MAC address can be found on the bottom of a plastic, pull-out tab on the front of the machine. Add this MAC to the DHCP config file /opt/services/dhcp/etc/dhcpd.conf in the appropriate compute node section. For example

host node-004 {
    hardware ethernet D4:AE:52:8B:61:06;
    fixed-address 10.1.34.14;
}

and restart dhcpd like so

/etc/init.d/nrao-dhcpd restart

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Configure TFTP

The DHCP config file specifies a filename. This filename is sent to the client so the client can download a boot kernel via TFTP. This process is probably already in place and does not need any altering for a new node.

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