startup messages on "headless" v20z server

On Tue, 04 Oct 2005 15:15:04 -0400, G Dahler

Well, I buttume that this "console redirection" is a BIOS option that sends the output to a serial port instead of the video (I don't know anything about Sun hardware and my buttumption is based on the way things work for PCs). I have a 64 node diskless cluster here where each node has no video card or keyboard. The reason you see the GRUB output but not the kernel messages is that the former uses BIOS calls, so the serial redirection works, but once the kernel is loaded, it takes over and the BIOS setting is no longer relevant. Kernel documentation claims that if a video card is not found, the first serial port will automatically become the console (once the appropriate options are enabled in the kernel config). In practice, I found this not to be the case and in fact I am seeing the same behavior on the serial line as you: GRUB messages, then nothing for a while, until a getty starts and I get a login prompt. I never bothered to fix this because I configured everything with a video card in. I would guess that either that kernel doc is out of date and you need to specify a boot parameter, or perhaps the ttyS0 node was not available on the ramdisk before udev was loaded.

-- Vladimir