Re: rc.d/zpool runs before ada(4) attaches

 
Van: Harry Schmalzbauer <freebsd_at_omnilan.de>
Datum: dinsdag, 1 december 2020 12:51
Aan: Ronald Klop <ronald-lists_at_klop.ws>, FreeBSD Current <freebsd-current_at_freebsd.org>
Onderwerp: Re: rc.d/zpool runs before ada(4) attaches
> 
> Am 01.12.2020 um 10:33 schrieb Ronald Klop:
> :
> :
> :
> >> One machine fails importing zpool because the correponding vdevs >> (ada0-ada2)
> >> are not available at the time rc.d/zpool runs.
> >>
> >>
> >> Adhoc  I'm not aware of any rc(8) vs. driver awareness.
> >> Is there any?
> >>
> >> Suggestions how to fix else than 'sleep 1'?
> >>
> >> Thanks,
> >>
> >> -harry
> >>
> >> P.S.: ahci(4) is compiled into kernel, machine is a HPE U48 (Gen 10 >> plus MicroServer), zfsloader loads root_MFS kernel module
> >>
> >
> >
> > There have been some changes to etc/rc.d/zpool in September.
> > Do you have the latest version? Compare with:
> > https://github.com/freebsd/freebsd/blob/master/libexec/rc/rc.d/zpool
> > or
> > https://svnweb.freebsd.org/base/head/libexec/rc/rc.d/zpool?revision=365354&view=markup >
> >
> > Otherwise it would be helpful for readers if you could post some logs > which indicate what is happening.
> > /var/run/dmesg.boot or the output of "dmesg"
> > Part of /var/log/messages
> > Part of /var/log/console.log if it exists.
> >
> 
> Thanks, I'm on -current from view days ago.
> The problem is that cam(4) is still probing devices, when rc.d/zpool runs, since mount_root_from succeeded, because it is a RAM disk, so succeeds independent of any real drive/controller probing.
> I can imagine of other seldom edgecases hitting the issue too.
> 
> So my proposed patch, working for me, looks like this:
> Index: libexec/rc/rc.d/zpool
> ===================================================================
> --- libexec/rc/rc.d/zpool       (revision 368202)
> +++ libexec/rc/rc.d/zpool       (working copy)
> _at__at_ -18,8 +18,16 _at__at_
> 
>   zpool_start()
>   {
> -       local cachefile
> +        local cachefile n=0 camlist=`camcontrol devlist -v`
> 
> +       # Wait for cam(4) devices attaching, 4 times at max by increasing
> +       # 1s each (10s max in total)
> +        while [ X"${camlist#*target*lun*probe}" != X"${camlist}" ]; do
> +               [ $n -lt 4 ] || break
> +               sleep $((n+=1))
> +               camlist=`camcontrol devlist -v`
> +       done
> +
>          for cachefile in /etc/zfs/zpool.cache /boot/zfs/zpool.cache; do
>                  if [ -r $cachefile ]; then
>                          zpool import -c $cachefile -a -N && break
> 
> best,
> -harry
> 
> 
> 

You can define these in /boot/loader.conf:
#kern.cam.boot_delay="10000" # Delay (in ms) of root mount for CAM bus
#kern.cam.scsi_delay="2000" # Delay (in ms) before probing SCSI

Maybe that helps.

Ronald.