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

[Brian Hesdorfer <zerophnx@gmail.com>]

On 4/18/2014 1:38 PM, Joost Roeleveld wrote:
> 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

Agreed! Hadn't heard of that option until you mentioned it. Learn a new 
thing everyday :)