[Beowulf] RE: A couple of interesting comments
Greg at keller.net
Wed Sep 24 07:37:12 PDT 2008
As a former installer/patsy at one of those nameless clumsy hardware
vendors, I thought this *may* be useful for you:
> 1. We specified "No OS" in the purchase so that we could install
> as our base. We got a set of systems with a stub OS, and an EULA for
> the diagnostics embedded on the disk. After clicking thru the EULA,
> tells us we have no OS on the disk, but does not fail to PXE.
Vendors get into all kinds of legal issues when they don't sell M$
licenses they are supposed to have EULA's for cover. They used to
clobber/corrupt partion tables etc. when fdisk'd ruthelessly but are
largely benign now if you handle issue #2 gracefully and get the
standard install/fdisk launched. The vendor I worked for had a EULA
free sku but only if you purchased RHEL WS licenses. Blank disks
Always had EULAs.
> 2. BIOS had a couple of interesting defaults, including warn on
> keyboard error (Keyboard? Not intentionally. This is a compute node,
> and should never require a keyboard. Ever.) We also find the BIOS is
> set to boot from hard disk THEN PXE. But due to item 1, above, we
> can fail over to PXE unless we load up a keyboard and monitor, and hit
> F12 to drop to PXE.
A fast trick I've used:
a. Keyboard errors are usually just complaint messages on a console
you'll never see. I haven't seen them halt a system during boot in
years so hopefully this is cosmetic.
b. to get around keyboarding through the BIOS config, a system with
hot swap drives can be simple:
Eject the drives
Boot the system (with ethernet cabled to a powered on switch)
Wait long enough for the system to post and decide there's no hard
drive, which bumps the PXE up to first boot
Power down, reinstall the drives - Now PXE is the primary boot device
This sounds more painful than it is. I've deployed a few 500+ and a
couple 1200+ node clusters and life was much faster and simpler this
Note: With many systems you can switch back to Disk as primary boot
device by powering off the ethernet switch and going through the 2
boot dance so the local drive becomes the primary boot device again.
We normally setup PXE to tell the node to boot local on the occasions
we need a stateful install. YMMV
Once the nodes are booted you can script the "Config" utility from the
vendor to tune the bios/bmc etc to your preferred favorite settings.
I use Perceus so the local drives are always scratch+swap space and we
partition them and format on the way up if they need it.
Hope this helps,
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