LinuxBIOS Questions.....

[Ronald G Minnich]

On 21 Oct 2002, Eric W. Biederman wrote:

> Personally I think booting from a local hard driver is a less
> manageable way to do things. I have booted a 1000 node cluster over
> the network in under a minute.

yep.

> The DOC has 8MByte of space, yes.  I don't use it and I don't see the
> need you can load a kernel from other places.  And in fact I consider
> it a poor choice for any but an embedded user to hard code their
> kernel, into the ROM.


Here is where Eric and I agree to disagree :-)

We really like having a kernel in DoC or IDE flash for our bproc Single
System Image clusters. We boot a linux from these things and it lets us do
all our cluster management over myrinet ... no ethernet needed. I don't
think it is really possible to do this type of thing via (e.g.)
etherboot for a long time.

Note, however, that all we do with that Linux in DoC is use it to boot
another linux. On our Alpha cluster, once we had flashed the Linux and
Initrd into flash, it stayed that way for a year (until we turned it off
in fact).


> Yes.  Though I try and keep reflashing down to just BIOS upgrades and
> not kernel upgrades.

That's for sure. But several companies (including lnxi.com) have done a
great job of making flash less failure-prone with a jumperless backup
scheme.

> > 4)  If you can coot the OS from he chip, how do you have access to all of
> > your libraries, etc?  Would you simply mount SOME file shares with libraries
> > and apps via NFS?

We are done with NFS here. We are using V9FS, which in conjunction with
Viro's changes to Linux (2.4.19 and later) give you private name spaces
for Linux, which are just incredibly nice. We're finding this to be pretty
robust, see http://v9fs.sourceforge.net.


ron