/lib64/rc/cache not writable!

[NikosAlexandris]

I hope this is the right forum for the following question.  I happily run ZFS on Funtoo.  In each power-off process, be it `shutdown` or `reboot`, there is this failure that's printed just before powering actually off: `/lib64/rc/cache not writable!`.

 

The directory exists and belongs to root:

stat /lib64/rc/cache/
  File: ?/lib64/rc/cache/?
  Size: 5         	Blocks: 1          IO Block: 512    directory
Device: 12h/18d	Inode: 481694      Links: 2
Access: (0755/drwxr-xr-x)  Uid: (    0/    root)   Gid: (    0/    root)
Access: 2016-11-22 03:23:11.605391160 +0100
Modify: 2016-10-24 23:20:18.612038472 +0200
Change: 2016-11-22 04:54:57.727073038 +0100
 Birth: -

Is this important?  How to proceed in understanding the problem?  I read through the (few) related threads on the web for it, like in https://archives.gentoo.org/gentoo-user/message/3e236160b893faf12eefed55283a8970.   No solution(s) however offered.

[Tassie_Tux]

I too have noticed this when testing Funtoo on ZFS root. The storage pool containing root is exported during shutdown so this message suggests that the export is occurring before OpenRC is finished with writing to /lib64/rc/cache.

 

The seriousness of this is debatable given that the system restarts without any obvious problems. Some research would be required.

[Oleg Vinichenko]

anything like /var or /usr used as separate zfs mounts?

[NikosAlexandris]

  On 11/22/2016 at 4:49 AM, Tassie_Tux said:

I too have noticed this when testing Funtoo on ZFS root. The storage pool containing root is exported during shutdown so this message suggests that the export is occurring before OpenRC is finished with writing to /lib64/rc/cache.

 

The seriousness of this is debatable given that the system restarts without any obvious problems. Some research would be required.

 

I remember reading this message for the last 2 years, always on ZFS, in laptop and desktop workstation.  The only problems I have had were right in the beginning, the first reboot(s), after completing the installation of Funtoo on ZFS and when building a new kernel. Albeit, it is known that re-building another (or newer) kernel needs to remember to re-compile ZFS related modules.  Since I rebooted quite some times the last days, while testing various kernel configurations, I decided it's time to deal with it.

 

(Off topic?)  However, I observe random freezing while booting the laptop the last days -- the boot sequence freezes, some times, at random points.  I am on

uname -a
Linux carbon 4.5.0-pf4 #1 SMP Mon Nov 21 11:36:43 CET 2016 x86_64 Intel(R) Core(TM) i7-4600U CPU @ 2.10GHz GenuineIntel GNU/Linux

Maybe the cause is some kernel mis-configuration (as I strive to customize the kernel to just fit to the hardware I run).  I tend to believe it happens when booting without AC plugged-in.

[NikosAlexandris]

  On 11/22/2016 at 8:05 AM, Oleg Vinichenko said:

anything like /var or /usr used as separate zfs mounts?

 

If zfs mounts are meant to be the mount points of ZFS datasets, then at least the one from the installation guide:

#  zfs create -o mountpoint=/var/tmp/portage -o compression=lz4 -o sync=disabled rpool/FUNTOO/build

In my very case, at the moment (while I plan to further split various system directories to occupy their own ZFS dataset):

...
xpool/FUNTOO/build         1.73G   302G  1.73G  /var/tmp/portage
...

[NikosAlexandris]

  On 11/22/2016 at 4:20 AM, NikosAlexandris said:

In each power-off process, be it `shutdown` or `reboot`, there is this failure that's printed just before powering actually off:

/lib64/rc/cache not writable!

...

I read through the (few) related threads on the web for it, like in https://archives.gentoo.org/gentoo-user/message/3e236160b893faf12eefed55283a8970.

 

As well, I think it is the same issue discussed (search for /lib64/rc) at http://www.mattzone.com/zfsonlinux/zfsonlinux_20140130.html