Date: Fri, 10 Sep 2010 08:58:29 -0700 From: Jeremy Chadwick <freebsd@jdc.parodius.com> To: Jeremie Le Hen <jeremie@le-hen.org> Cc: pluknet <pluknet@gmail.com>, freebsd-stable@freebsd.org Subject: Re: Cannot install using serial console Message-ID: <20100910155829.GA15704@icarus.home.lan> In-Reply-To: <20100910153830.GA15012@icarus.home.lan> References: <20100907145028.GF16902@felucia.tataz.chchile.org> <AANLkTi=qhUspTMaW-608TKhVZ9PJHBydhQHKQCiwgb6b@mail.gmail.com> <20100910111434.GU16902@felucia.tataz.chchile.org> <20100910112726.GA9262@icarus.home.lan> <20100910151800.GX16902@felucia.tataz.chchile.org> <20100910153830.GA15012@icarus.home.lan>
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On Fri, Sep 10, 2010 at 08:38:30AM -0700, Jeremy Chadwick wrote: > On Fri, Sep 10, 2010 at 05:18:00PM +0200, Jeremie Le Hen wrote: > > On Fri, Sep 10, 2010 at 04:27:26AM -0700, Jeremy Chadwick wrote: > > > > > As far as I know you need also to enable a serial terminal in /etc/ttys. > > > > > > > > Yeah, this came to my mind too but I check on the installation CD, there > > > > is no /etc/ttys. > > > > > > This is normal. > > > > > > Can you try hacking up a solution for yourself based on what I've > > > documented with regards to PXE booting? There will be pieces which > > > obviously don't apply to you because you're booting from physical media, > > > but some of the adjustments (to the bootloader, etc.) you can try. > > > > > > http://jdc.parodius.com/freebsd/pxeboot_serial_install_8.html > > > > But as far as I understand the handbook, this is not required to perform > > the installation through sysinstall(8) on a serial console. Modifying > > /boot/loader.conf on the installation media is enough according to > > chapter 2.12.1. Am I wrong? > > Nah you're not wrong -- I'm just not sure what the VM might be doing > with/to the serial port. I don't know what KVM you're using on Linux, > but does the VM machine have a BIOS? If so, does it offer something > like serial console redirect capability? If so, and it's enabled, it > could/might be conflicting with the OS. > > The reason I mention this: on some x86 systems that offer BIOS-level > console redirection capability, the kernel (confirmed on both FreeBSD > and Linux) can, depending on circumstances I'm not sure of, lock up the > OS hard. > > If the VM offers such a feature and you're not using it, try it (and > remove the comconsole stuff from your loader.conf). You might end up > with VGA-over-serial that way, and it might suffice. > > I imagine some form of getty(8) must be in use under the FreeBSD > installation environment, because you can switch virtual consoles via > Alt-<F1/F2...> as I'm sure you know. > > > > One thing worth pointing out is that you stated the system that you're > > > trying to use serial console on is actually running under a VM on Linux: > > > > > > > I tried to install FreeBSD (201008 -CURRENT snapshot, but I don't think > > > > it's important here) in a KVM-backed virtual machine on a headless Linux > > > > host, following section 2.12.1 of the handbook. > > > > > > Can you provide a full dmesg prior to the "/stand/sysinstal" output > > > happening? You don't need to boot verbose (yet), but it would help with > > > regards to determining what the kernel is seeing device-wise. Yes it > > > matters. > > > > Yes, I've actually already posted it in my original message: > > http://lists.freebsd.org/pipermail/freebsd-stable/2010-September/058703.html > > Thanks much -- for some reason that part of the Email is missing for me. > > uart0: <Non-standard ns8250 class UART with FIFOs> port 0x3f8-0x3ff irq 4 flags 0x10 on acpi0 > uart0: [FILTER] > uart0: console (9600,n,8,1) > > It sure looks like it's console, but I'm not sure if there are > implications/bugs that might stop serial I/O from working past a certain > point for this type of chip, especially when under a VM. > > Only other things I can think of trying, one at a time: > > - Explicitly set a serial port speed using comconsole_speed in > loader.conf > - Adding boot_serial="yes" to loader.conf > - Try booting with ACPI disabled. I'm not sure this will work under a > VM, but worth a shot I guess Some other things that occurred to me: 1) Is the kernel built with SMP support? I imagine that the stock "out-of-the-box" images have SMP in use. I don't know what happens on FreeBSD if "options SMP" is present on a system which appears to lack SMP (your dmesg output indicates only one CPU). 2) Does this problem happen with RELENG_8 (e.g. 8.1-RELEASE or an 8.1-STABLE snapshot)? 3) Can you try booting a livefs CD image (with loader.conf adjusted to contain console="comconsole") and see if the behaviour is the same? I'm trying to figure out if it's something sysinstall somehow induces (I imagine there's a little delay between the console output and when the sysinstall binary has actually started), or if the kernel is doing something. -- | Jeremy Chadwick jdc@parodius.com | | Parodius Networking http://www.parodius.com/ | | UNIX Systems Administrator Mountain View, CA, USA | | Making life hard for others since 1977. PGP: 4BD6C0CB |
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