20080331

One moment please, I'll connect you...

Today's topic has been a recurring theme during the past few weeks.

On the one hand, while I'm in love with my iPhone for email and web access pretty much everywhere, I still really miss having an SSH client on my hip. (On my Treo, the pssh client did the trick. It was simple, talked SSH v2, had a poor random number generator, but could import strong pre-shared keys from a Palm memo.) I'm hoping that a simple, cool new SSH terminal app for the iPhone is just around the corner, now that the iPhone Software Developer Kit is out. I don't need fancy key-mapping, or a variety of terminal emulations. If it can offer to let me talk to Bluetooth devices as well as the Edge/WiFi connections (so I can use my Blue Console devices, it will be worth more to me. (That's a blatant plea/hint to any iPhone developers. Hopefully I've said iPhone enough times for this article to turn up in a web search. :-)

On the other hand, I've found the Service Processor on some SUN Opteron boxes to be a bit vexing. Many hosts have these Service Processors (S.P. from here on) on-board now, and each vendor is implementing it a bit differently. It's an added 'black box' on the communications line between the physical serial port and the serial I/O (tty) port on the host.

When BIOS Redirection was added, this was the first complication making serial ports provide the GETTY console login under a Linux host. Now these processors, supporting ILOM/ALOM/e-i-e-i-o communications are also listening to the line, looking for meta-sequences, waiting to interrupt the conversation and do your bidding. One gotcha is, when you start talking to the S.P., you lose any logging from the Operating System. (Why don't these special purpose computers BUFFER at least SOME amount of host data?)

The odd hang-up with the SUN units I'm wrestling seems to be an inactivity timeout. If I get into the S.P., and let it sit for a while, it seems to go to sleep, and I can't wake it up again. BUT, it never returned the connection back to the OS. Essentially, the O.S. console connection is now bottled-up, and I can't get the S.P. to answer through the serial port, or to relinquish the port back to the O.S., leaving me to reboot the system in order to get the serial console back. There MUST be a better way.

Fortunately, there is a good write-up on the SUN S.P., and I'm going to go over it this weekend. Hopefully I'll find some variables to change the meta characters which trigger the S.P., since they are too close to another sequence I need to send, and I also hope to find some timer settings to get the S.P. to drop out politely if I time out of the session.

-Z-

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