On 2002.01.30 02:37 Bob Staaf wrote: > I have a few PowerEdge 2450s running Red Hat 7.2 and I just aquired a > Cyclades TS1000 terminal server and I would like to use it for console > access to these servers. My question is, can you redirect the console to > the serial port AND still have normal access to the server through the > video port. I guess it hinges on what "redirect" means :) I am hoping > it is > not the literal definition as I need access both ways.
Yes. For details of the Linux aspects see http://www.aarnet.edu.au/~gdt/serialconsole/ which is about to become the second edition of the Remote-Serial-Console-HOWTO just as soon as I've tested it with Red Hat Linux 7.2's GRUB boot loader. The differences from the HOWTO in setting up GRUB are serial --unit=0 --speed=9600 --word=8 --parity=no --stop=1 terminal --dumb serial console title ... kernel /vmlinuz-2.4.9-21 ro root=/dev/hda6 console=tty0 console=ttyS0,9600n81 and remove the "splashimage". Then continue on to change /etc/inittab to start a getty on the serial line and do the incidentals like fixing kudzu and PAM. There is a bug with the Dell serial BIOS code -- typing one character during boot will leave the machine hanging in the BIOS. This can be a problem with some modems, which let the RxData line float when the Carrier Detect line is not asserted. The RS-232 standard would expect these characters to be discarded. As Dell probably want to let people get by with a three wire RS-232 connection that should at least make entering the BIOS configuration less suseptable to on-hook line noise. You might want to attach a breakout box with LEDs that show the RS-232 signals to see if you are going to encounter this problem with the TS1000. I'd appreciate some screen captures of configuring the BIOS for serial I/O, if that's OK. Finally, there's a nasty choice that the future HOWTO needs to draw out better. Your terminal server will keep seeing Carrier Detect drop during boot. Unfortunately the serial UART keeps being reset; by the BIOS, boot loader, Linux and getty. These resets drop DTR, which is usually wired to DCD and DSR in a null modem cable. So if your terminal server listens to DCD you will keep seeing the link hang up and miss boot messages. Equally, if your terminal server ignores DCD then you won't clear the line down should a sysadm kill the session on the serial port. The HOWTO will probably suggest that you listen to DCD if there are scenarios where the remote serial console is the only way of reaching the machine. This is safe, but a real pain (modem users basically can't watch the boot messages). What's really needed is some cooperation between the boot loader, kernel and getty. I haven't bothered with this as as I can't yet face the aggravation of getting a minor patch (a parameter not to reset the UART) applied into six code bases. -- Glen Turner Network Engineer (08) 8303 3936 Australian Academic and Research Network [EMAIL PROTECTED] http://www.aarnet.edu.au/ -- The revolution will not be televised, it will be digitised _______________________________________________ Redhat-list mailing list [EMAIL PROTECTED] https://listman.redhat.com/mailman/listinfo/redhat-list
