[rescue] Cray J90s

[Jonathan Katz]

Dave wrote:
> That's why CS6400s aren't more popular than they are amongst the
> supers-at-home community, I suspect.

Yeah, there will be E10Ks in homes in 10 years, too if you think
it through. Right now you can d/l all the necessary software from
Sun. The trick becomes the licenses to generate the software-PROM.

The same Solaris 8 ISOs you download for your Blade 100 will boot
an E10K. The SSP software comes with the Media Kits now and can
be found at www.sun.com/downloads.

The CS6400 is more tricky. They stopped support in Solaris 2.6 and
you need a special 2.6 CD to get one running. It takes an older
rev of the SSP software that isn't public, either. As mentioned
before it also requires the special JTAG cable and card in the
SSP.

Without the JTAG card in the SSP there is *no* way to get to the
console as if it were a virgin system you're bringing on-line
for the first time. The CS6400 *is* designed to come up without
an SSP if one is missing, so if you happen to get one with the
OS disks still loaded and attached you should be OK. The
software-PROM image which winds up in the control board stays
resident in an NVRAM on that control board if my logic holds true. 
If the system is setenv auto-boot? true and all the SCSI disks
are in place it should come up.

Now this is where my inexperience with the cs6400 makes everything
supposition. With an E10K after a certain point in the Solaris
boot process the console is handed off to a TCP/IP session between
the private** network between the SSP and an ethernet port on a
configured domain. Since the software for this process is derived
from the CS6400 stuff (the software is called 'cvc/cvcd -- Cray
Virtual Console Daemon) I'm assuming this stuff holds true for
the CS6400. After the CS6400 comes up (and without a console there'd
be no way to tell if it came up except for constantly checking the
blinky-lights) a system with the SSP software installed could 'snoop'
the local network during the boot process and possibly see packets
the system is requesting so the IP addresses and MAC addresses of the 
CS6400 could be learned. Once this information is configured on
the 'SSP' that SSP could be used to fire up a CVC session over the
TCP/IP network using the 'netcon' utility. If this were to succeed
you'd then have console access to the domain running on the CS6400.

I'm leaving out a lot of unknown details. There are about a dozen
files which would probably need changing somewhere on the SSP to
make this work, and the SSP may need a reboot. However, once you
have console access to the domain you can reboot it into single
user mode (where I think cvcd will fire up... if I had an E10K SSP
handy I could go into /etc/rc*.d and see where cvcd starts) or
use the tricks discussed before (using FORTH) to set root's
password, etc.

The *if* of getting a working system with a working install on
it is the lynchpin to this (admittedly flakey) process.

**lots of sites don't use a private network for console/admin
stuff on their E10K domains. Shame on them, it's not a best
practice and not safe.

-Jon