Re: [gentoo-user] Allow delay for booting from USB device?

[Joost Roeleveld <joost@antarean.org>]

On Friday 18 April 2014 10:01:35 Brian Hesdorfer wrote:
> On 4/18/2014 9:05 AM, Joost Roeleveld wrote:
> > On Friday 18 April 2014 12:02:01 Thomas Mueller wrote:
> >> Is there a way to make Gentoo or other Linux allow extra time when root
> >> is
> >> on a USB device?  Any way to say "just a second" or more like 15 seconds
> >> before aborting with the message that root partition does not exist?
> >> 
> >> In this case it's an IDE hard drive in a USB enclosure.
> >> 
> >> FreeBSD seems to handle this situation better.  I would get a
> >> mountroot>
> >> prompt, to which I would respond
> >> ufs:/dev/ada0p3
> >> and be good.
> >> 
> >> I could avoid this situation with /boot/loader.conf
> >> 
> >> legal.realtek.license_ack=1
> >> rsu-rtl8712fw_load="YES"
> >> kern.cam.scsi_delay="13000"     # Delay (in ms) before probing SCSI
> >> kern.cam.boot_delay="16000"    # Delay (in ms) of root mount for CAM bus
> >> hint.re.0.disabled="1"
> >> 
> >> but don't know if Linux has anything like this.
> >> 
> >> Only lines 3 and 4 are relevant to this issue; other lines are for
> >> different issues.
> >> 
> >> Tom
> > 
> > Try adding " rootdelay = 15 "  to the kernel commandline.
> > This should make the kernel wait 15 seconds before trying to access the
> > root- device.
> > 
> > See:
> > http://www.linuxtopia.org/online_books/linux_kernel/kernel_configuration/r
> > e58.html
> > 
> > I used this myself in the past when booting from USB-devices.
> > 
> > Kind regards,
> > 
> > Joost
> 
> Tiny Core linux, which is primarily booted over usb, does something
> similar. If I'm understanding this right, they have a loop in their
> initrd that just waits a maximum of X seconds until it shows up.
> 
> I'm not sure how easy this would be to move into something else.
> 
> Lines 114-128:
> http://git.tinycorelinux.net/index.cgi?url=Core-scripts.git/tree/etc/init.d/
> tc-config

" rootdelay " is a standard linux kernel option. No need to use a special 
script.

--
Joost