Re: Preserving early console output (pre-Copyright stuff)
On Thu, Jul 01, 2010 at 11:44:52AM -0400, Matthew Mondor wrote: Sometimes I've been thinking about this as more and more hardware don't ship with RS232 anymore. Is there a relatively common BIOS interface which would allow, even if non-efficiently, to use a USB port as a serial device without too much code? If so, possibly that a special usb-serial bootblock could be using that sometime in the future? It is probably easier to get the data into ethernet packets than USB! David -- David Laight: da...@l8s.co.uk
Re: Preserving early console output (pre-Copyright stuff)
On Thu, Jul 01, 2010 at 05:18:36AM -0700, Paul Goyette wrote: b) a way to pause long enough to manually transcribe the output? (A simple timed delay would work, although a Press any key to continue would be easier!) It may work to do printf(Press a key...\n); cnpollc(1); (void)cngetc(); cnpollc(0); ... it used to, but that was ~15 years ago. -- David A. Holland dholl...@netbsd.org
Preserving early console output (pre-Copyright stuff)
I'm trying to debug some stuff on a new server, and there are some messages of interest that get printf'd on the console very early in the system's life, before the Copyright (c)... lines. There is a large amount of info being printed, way more than a screenful and way more than can be captured with an eyeball snapshot. Unfortunately, it seems that this information is NOT retained in the kernel's message buffer, so it never gets collected by syslog. (For those who want to know details, some of the messages in question are generated by add_mem_cluster() in src/sys/arch/x86/x86/x86_machdep.c) So, is there either a) a way to capture these messages in the normal message buffer for later collection by syslog, or b) a way to pause long enough to manually transcribe the output? (A simple timed delay would work, although a Press any key to continue would be easier!) Thanks in advance! - | Paul Goyette | PGP Key fingerprint: | E-mail addresses: | | Customer Service | FA29 0E3B 35AF E8AE 6651 | paul at whooppee.com| | Network Engineer | 0786 F758 55DE 53BA 7731 | pgoyette at juniper.net | | Kernel Developer | | pgoyette at netbsd.org | -
Re: Preserving early console output (pre-Copyright stuff)
On Thu, Jul 01, 2010 at 05:18:36AM -0700, Paul Goyette wrote: a) a way to capture these messages in the normal message buffer for later collection by syslog, or b) a way to pause long enough to manually transcribe the output? (A simple timed delay would work, although a Press any key to continue would be easier!) I don't know of an easy way to do either (although I could see adding something to pause every N calls if it's not logging yet), but this is the kind of thing that a serial console can be really handy for. Do you have serial ports on the system in question? -allen -- Allen Briggs - bri...@ninthwonder.com
Re: Preserving early console output (pre-Copyright stuff)
On Thu, 1 Jul 2010 05:18:36 -0700 (PDT) Paul Goyette p...@whooppee.com wrote: b) a way to pause long enough to manually transcribe the output? (A simple timed delay would work, although a Press any key to continue would be easier!) Get a semi-decent digital camera, set high ISO speed in a well lit room and take a snapshot of the screen. Might take you a few tries to capture all data, but it may be quicker than figuring out how to set up serial console. If the image is too blurry, increase the ISO + add more light.
lockdebug messages in dmesg (was: Preserving early console output (pre-Copyright stuff))
btw, is this intentional that lockdebug panic messages dont end up in dmesg? -- NetBSD - Simplicity is prerequisite for reliability
Re: Preserving early console output (pre-Copyright stuff)
On Thu, Jul 01, 2010 at 06:00:41AM -0700, Paul Goyette wrote: There is a serial port, but I haven't figured out yet how to make it work in the BIOS. And while I do have other machines with serial ports I've never used those ports and don't even have serial cables! (The last time I used a serial cable was way back in the days of modems and dial-up 'net access!) Heh. You do need a serial cable and another computer, but it's not too hard to set up. You don't need to find any options in the BIOS if you install the right boot blocks. The pause every N calls is probably over-kill - I'd be happy to pause on every call, if there is an appropriate pause() function that can be called at this early part of the boot process. You could always do a simple spin-loop. Assuming this is a temporary thing you're doing for a single (or limited number of) system(s). -allen -- Allen Briggs - bri...@ninthwonder.com
Re: Preserving early console output (pre-Copyright stuff)
On Thu, 1 Jul 2010 06:00:41 -0700 (PDT) Paul Goyette p...@whooppee.com wrote: That's what I thought I'd get for an answer! :) There is a serial port, but I haven't figured out yet how to make it work in the BIOS. And while I do have other machines with serial ports I've never used those ports and don't even have serial cables! (The last time I used a serial cable was way back in the days of modems and dial-up 'net access!) Sometimes I've been thinking about this as more and more hardware don't ship with RS232 anymore. Is there a relatively common BIOS interface which would allow, even if non-efficiently, to use a USB port as a serial device without too much code? If so, possibly that a special usb-serial bootblock could be using that sometime in the future? If there is no BIOS common interface, I can see it's a problem because of all the driver code that'd be needed at boot time... Thanks, -- Matt
Re: lockdebug messages in dmesg (was: Preserving early console output (pre-Copyright stuff))
On Thu, Jul 01, 2010 at 04:13:36PM +0200, Adam Hoka wrote: btw, is this intentional that lockdebug panic messages dont end up in dmesg? Yes, just because that requires taking additional locks. -- NetBSD - Simplicity is prerequisite for reliability
Re: Preserving early console output (pre-Copyright stuff)
On Thu, 1 Jul 2010, Allen Briggs wrote: Heh. You do need a serial cable and another computer, but it's not too hard to set up. You don't need to find any options in the BIOS if you install the right boot blocks. Yeah, OK, I got a cable, plugged it in, run cu(1) on one end, and added a new entry to the /boot.cfg on the other end: menu=Serial/Single/Verbose/Debug:consdev com0; boot -svx Then just boot, and things magically work! Thanks for the clue-by-four - | Paul Goyette | PGP Key fingerprint: | E-mail addresses: | | Customer Service | FA29 0E3B 35AF E8AE 6651 | paul at whooppee.com| | Network Engineer | 0786 F758 55DE 53BA 7731 | pgoyette at juniper.net | | Kernel Developer | | pgoyette at netbsd.org | -
Re: Preserving early console output (pre-Copyright stuff)
Matthew Mondor mm_li...@pulsar-zone.net wrote: Sometimes I've been thinking about this as more and more hardware don't ship with RS232 anymore. Is there a relatively common BIOS interface which would allow, even if non-efficiently, to use a USB port as a serial device without too much code? I doubt it. All uses of serial-via-USB that I've seen have required electronics (often buggy electronics) to do the conversion, and the one or two USB video interfaces I've also seen have also required electronics _and_ custom kernel drivers, and (you guessed it) there were bugs galore there too in the one I tried (hardware, software, or both I don't know). On the big iron I used to work with that had consoles with network support, the network connection was a pretty dumb piece of hardware which spoke ssh or telnet on the network side ... and RS-232 on the console side. :-( (OK, it also offered remote access to the reset and power switches, but the console was still -- in the 21st century -- based off RS-232. Maybe that changed in later models, but I wouldn't bet much on the possibility.) A USB console is a nice idea, but the industry doesn't seem to have picked it up(*). Which with all the EFI, IPMI, and other overly complex industry standards necessary to build a modern machine plus the prevalence of notebook PCs all with USB ports this is amusing, if you have a warped enough sense of humour ... (*) Or if there _is_ a USB console standard I've missed the memo and would welcome someone setting me straight, please. Regards, Giles
