[SOLVED] slackware-current install on USB - .. can't find /mnt in /etc/fstab

slackware64-current (16. 3. 2020)
install on USB disk

As kernel do not have compiled in USB devices, I created initrd.
Suggested by mkinitrd_command_generator.sh do not include USB modules:

mkinitrd -c -k 5.4.25 -f ext4 -r "UUID=202a8463-30c8-4806-8631-02a54da3090b" -m usb-storage:xhci-hcd:jbd2:mbcache:crc32c_intel:crc32c_generic:ext4 -u -o /boot/initrd.gz

Also at boot time created initrd from above code returned

errors: jbd2: exports duplicate symbol jbd2_journal_restart (owned ky kernel) modprobe ERROR: could not insert 'jbd2+: exec format error

The same error was with ext4 and mbcache modules.

So I created own code, I used years ago:

mkinitrd -c -k 5.4.25 -f ext4 -r UUID=202a8463-30c8-4806-8631-02a54da3090b -m usb-storage:xhci-hcd:xhci-pci:ohci-pci:ehci-pci:uhci-hcd:ehci-hcd:hid:usbhid:i2c-hid:hid_generic:hid-cherry:hid-logitech:hid-logitech-dj:hid-logitech-hidpp:hid-lenovo:hid-microsoft:hid_multitouch:jbd2:mbcache:crc32c_intel:crc32c_generic:ext4 -u -o /boot/initrd.gz

As you can see, a root device is named by UUID.
/etc/fstab line for mount root partition:

PARTUUID=fe50e8fe-01        /                ext4        defaults         1   1

The lilo.conf general par do not include boot= instead there is:

append=" root=PARTUUID=fe50e8fe-01 "

The boot partition part is:

image = /boot/vmlinuz
  initrd=/boot/initrd.gz
#  root = /dev/sdc1
  label = Slackware
  read-only  # Partitions should be mounted read-only for checking
# Linux bootable partition config ends

The above settings worked with slackware64-current install two years ago.

Now at boot from USB disk ends with:

mount: can't find /mnt in /etc/fstab ERROR: No /sbin/init found on rootdev (or not mounted). Trouble ahead. You can try to fix it. Type 'exit' when things are done.

Found a workaround on that forum:

mount -o ro -t ext4 /dev/sda1 /mnt
exit

After that, boot continues and finishes without error.
All works including KDE.

Have tried many versions in fstab and lilo.conf - naming of boot partition by PARTUUID, by /dev/sdXX. None works.

How to permanently solve that problem?

booting from usb maybe it is useful to add -w 5 option,
it will wait for five seconds to usb devices be ready.

Also my modules line is a little bit different,
but I think jbd2 and mbcache aren't needed, with ext4 on the list
they will be added automatically.

Thanks.

Not sure will help, but where to put -w 5 option? Lilo?
Please post exact line and in which script.
Regarding modules in a mkinitrd:
/boot/initrd-tree/modules.dep:

kernel/fs/ext4/ext4.ko: kernel/fs/mbcache.ko kernel/fs/jbd2/jbd2.ko

The other question. Why do I must include ext4 module in a initrd? Look in a compiled kernel .config is a line:

CONFIG_EXT4_FS=y

- compiled in kernel.
So default Slackware huge kernel have built in ext4 AND also module (found in a installed /lib/modules)

https://docs.slackware.com/howtos:sl...sistent_naming
hi,
to build the initrd.gz you use

UUID=202a8463-30c8-4806-8631-02a54da3090b

and in lilo you use

append=" root=PARTUUID=fe50e8fe-01 "

it worked for you before that way i guess ? using UUID at my end for lilo/fstab/mkinitrd.

Originally Posted by _peter https://docs.slackware.com/howtos:sl...sistent_naming hi, to build the initrd.gz you use UUID=202a8463-30c8-4806-8631-02a54da3090b and in lilo you use append=" root=PARTUUID=fe50e8fe-01 " it worked for you before that way i guess ? using UUID at my end for lilo/fstab/mkinitrd.

The above is all already used in my scripts. The boot continues after manually mount when stop before initrd. Read my first post please.

sorry, i meant use UUID instead of PARTUUID in your lilo configuration

I don't think that lilo.conf accepts a naming by PARTUUID (partition's UUID). Try with UUID (file system's UUID) instead.

Also, what says "lilo -t"?

Originally Posted by _peter sorry, i meant use UUID instead of PARTUUID in your lilo configuration

That worked 2 years ago.
An what else can I use to define USB disk by ID instead of /dev/SDXX. In append parameter of lilo.config?

the below should give you a list of the connected drives UUID - including usb -

ls -la /dev/disk/by*

use didier recommendation as well on the -t option while executing lilo.

this is the UUID syntax for your lilo.conf

   root=<root-device>
              This specifies the device that should be mounted as root.  It may be specified  as  a
              global  option.   If  the special name current is used, the root device is set to the
              device on which the root file system is currently  mounted.  If  the  root  has  been
              changed  with  -r , the respective device is used. If the variable `root' is omitted,
              the root device setting contained in the running kernel image is used.  Warning: This
              can induce to an unbootable system!

              The  root  filesystem  may  also  be  specified by a LABEL= or UUID= directive, as in
              '/etc/fstab'.  In this case, the argument to root=  must  be  enclosed  in  quotation
              marks, to avoid a syntax error on the second equal sign, e.g.:

                   root="LABEL=MyDisk"
                   root="UUID=5472fd8e-9089-4256-bcaa-ceab4f01a439"

              Note:    The   command   line   root=   parameter  passed  to  the  kernel  will  be:
              'root=LABEL=MyDisk'; i.e., without the quotation marks. If  the  root=  parameter  is
              passed  from  the  boot  time  boot: prompt, no quotes are used.  The quotes are only
              there to satisfy the requirements of the boot-installer parser, which treats an equal
              sign  as  an operator.  The kernel command line parser is very much simpler, and must
              not see any quotation marks.  Simply stated, only  use  the  quotation  marks  within
              /etc/lilo.conf.

this thread from 2018 is clear, especially posts #4 & #7 by one of the wiki's author

Originally Posted by zdolar Thanks. Not sure will help, but where to put -w 5 option? Lilo? Please post exact line and in which script. Regarding modules in a mkinitrd: /boot/initrd-tree/modules.dep: kernel/fs/ext4/ext4.ko: kernel/fs/mbcache.ko kernel/fs/jbd2/jbd2.ko The other question. Why do I must include ext4 module in a initrd? Look in a compiled kernel .config is a line: CONFIG_EXT4_FS=y - compiled in kernel. So default Slackware huge kernel have built in ext4 AND also module (found in a installed /lib/modules)

Excuse me, I really wasn't clear. -w options is for mkinitrd.

mkinitrd -c -k 5.4.25 -w 5 -f ext4 ...etc

When I run mkinitrd with a module list like '-m ext4:jbd2:mbcache' the output shows jbd2 and mbcache
being added twice, I think this isn't a problem, but I always run '-m ext4' and it works.

If you run the huge kernel there isn't need of adding ext4 to the initrd, as you wrote it is in the kernel.


My experience running Slackware from a usb disk it that even the huge kernel needs the usb modules to boot.
This is from some years ago so maybe that changed, I don't know.

I found my mkinitrd command line to boot from usb.

-m ext4:xhci-pci:xhci-plat-hcd:usb-storage:ehci-pci:ehci-platform:ohci-pci:ohci-platform

IIRC xhci-pci and xhci-plat-hcd are for USB 3
ehci-pci and ehci-platform are for USB 2
ohci-pci and ohci-platform are for USB 1.1

Paulo2 many thanks for the help!


A key was -w 5 in a mkinitrd script! All other options were correct all the time.


Years ago, when I did that I used SSD disk, now I tested with spare old hard disk. So at a past there was no need to use -w, with that old disk it is a must.

The complete manual for creating initrd in /boot after installing slackware from media:
Needed procedure when booting installed slackware from a USB device.

DO NOT reboot after slackware install in a USB disk, instead follow this manual.

Installed Slackware from a USB disk - no kernel USB drivers in kernel, only modules


replace ALL occurrences of a partition names /dev/.. with PARTUUID get by blkid

/etc/fstab:

PARTUUID=fe50e8fe-01 / ext4 defaults ...

lilo.conf

general part:

append=" root=PARTUUID=fe50e8fe-01 "

- spaces at start and end!

Bootable partition part:

addappend=" kernel config options " initrd=/boot/initrd.gz

Creating initrd:

After booting with the install stick, open two terms (with CTRL-ALT-F1 and CTRL-ALT-F2). use the first terminal to mount partitions properly, e.g. :

mkdir /mnt/slash mount -t ext4 /dev/boot_partition /mnt/slash

Then I built a jail in /tmp with the following script :

dirs="/dev \ /proc \ /sys \ /mnt/slash/bin \ /mnt/slash/boot \ /mnt/slash/etc \ /mnt/slash/home \ /mnt/slash/lib \ /mnt/slash/lib64 \ /mnt/slash/lost+found \ /mnt/slash/media \ /mnt/slash/mnt \ /mnt/slash/opt \ /mnt/slash/root \ /mnt/slash/run \ /mnt/slash/sbin \ /mnt/slash/srv \ /mnt/slash/tmp \ /mnt/slash/usr \ /mnt/slash/var" for d in $dirs ; do mkdir -p /tmp/jail/`basename $d` && mount -B $d /tmp/jail/`basename $d`; done

In the second terminal (CTRL-ALT-F2) I do a chroot, and ran mkinitrd_command_generator.sh :

chroot /tmp/jail /usr/share/mkinitrd/mkinitrd_command_generator.sh

This generates mkinitrd line, that must be executed like this:

mkinitrd -c -k 5.4.25 -w 5 -f ext4 -r UUID=202a8463-30c8-4806-8631-02a54da3090b -m usb-storage:xhci-hcd:xhci-pcihci-pci:ehci-pci:uhci-hcd:ehci-hcd:hid:usbhid:i2c-hid:hid_generic:hid-cherry:hid-logitech:hid-logitech-dj:hid-logitech-hidpp:hid-lenovo:hid-microsoft:hid_multitouch:jbd2:mbcache:crc32c_intel:crc32c_generic:ext4 -u -o /boot/initrd.gz

The abovel line MUST have UUID name of a root partition instead /dev/sd..
Replace kernel number accordingly.

run lilo:

lilo -r /root_mount_point -b /boot_disk

-r /mnt/hd/root
-b /dev/sdb - disk, not partition!

reboot