Hi J. R. Okajima,
Since I am new to Aufs, my explanation may be inadequate.
I am able to see the /rootfs folder in the / after the mount --move in
initramfs.
snapshot of init file from initramfs
mount -o noatime,ro -t ext3Â Â Â /dev/mmcblk0p1Â Â Â Â Â Â /rootfs
mount   -o   rw   -t   tmpfs   aufs-tmpfs   /rw
mount -t aufs -o noatime,br=/rw=rw:/rootfs=ro none /aufs
mkdir -p /aufs/rootfs
mount --move /rootfs /aufs/rootfs
exec switch_root /aufs /sbin/init
Â
Now I want to use the /rootfs in rw mode.
so I do this by using the command below.
mount -o remount, br:/rootfs=rw /rootfs
I get the below message on the shell and mount command reflect rw change for
/rootfs record.
snapshot of mount display on shell.
mount
rootfs on / type rootfs (rw)
none on /dev type devtmpfs
(rw,relatime,size=115240k,nr_inodes=28810,mode=755)
/dev/mmcblk0p1 on /rootfs type ext3
(ro,noatime,errors=continue,user_xattr,acl,barrier=0,data=writeback)
aufs-tmpfs on /rw type tmpfs (rw,relatime)
none on / type aufs (rw,relatime,si=4ee1c431)
none on /dev type devtmpfs
(rw,relatime,size=115240k,nr_inodes=28810,mode=755)
proc on /proc type proc (rw,relatime)
tmpfs on /mnt/.splash type tmpfs (rw,relatime,size=40k)
sysfs on /sys type sysfs (rw,relatime)
none on /dev type tmpfs (rw,relatime,size=1024k,nr_inodes=8192,mode=755)
/dev/mmcblk0p2 on /media/mmcblk0p2 type ext3
(rw,relatime,errors=continue,user_xattr,acl,barrier=0,data=writeback)
/dev/sda2 on /media/sda2 type ext3
(rw,relatime,errors=continue,user_xattr,acl,barrier=0,data=writeback)
/dev/sda1 on /media/sda1 type ext3
(rw,relatime,errors=continue,user_xattr,acl,barrier=0,data=writeback)
devpts on /dev/pts type devpts (rw,relatime,gid=5,mode=620)
Things I tried after the above step.
I create a new file in home directory with some text info embedded.
then I remount to read only using the above command.
mount -o remount, br:/rootfs=ro /rootfs/
Now,I am not able to see the ro change in /rootfs.
After rebooting the file created in rw mode is missing in filesystem.
Please educate me if I am missing any info/step.
With Regards,
Ratheendran
On Tue, Dec 23, 2014 at 10:48 AM, <[1]sf...@users.sourceforge.net> wrote:
Ratheendran R:
> Now after the switch_root call from init of initramfs the mount /rw /ro
and
> /aufs are cleaned.
>
> exec switch_root /aufs /sbin/init
>
>
> The mount point is not accessible ,Please correct me if my understanding
is
> wrong.
??
Do you mean that after switch_root you cannot see anything under the
root dir?
Would you post the output of "stat /" after switch_root?
J. R. Okajima
References
1. mailto:sf...@users.sourceforge.net
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