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

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

[Thomas Mueller]

Thanks to Joost Roeleveld and Brian Hesdorfer for helpful answers.

Even before getting the new email, I googled on linux boot root delay and found the answer where previous Google search failed to yield results.

That was an old Linux, Slackware 13.0 with kernel 2.6.29.6 where I remember trying to get started with Gentoo but the kernel I built, compile time 130 minutes, failed to boot.  It still took many attempts before I was successful with the boot.  No Internet access because the kernel is too old and the Ethernet too new.

Tom

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

[Jonathan Callen]

-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA512

On 04/18/2014 01:49 PM, Brian Hesdorfer wrote:
> 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 :)
> 
> 

There is also a "rootwait" option, which simply waits until the root device is available, no
matter how long that takes. (So you don't end up waiting longer than required "just in case").

- -- 
Jonathan Callen
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v2.0.22 (GNU/Linux)
Comment: Using GnuPG with Thunderbird - http://www.enigmail.net/
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=S+Ff
-----END PGP SIGNATURE-----