How to Create a Trans Metadevice for a File System That Can Be Unmounted (Command Line)

After checking the prerequisites ("Prerequisites for Creating DiskSuite Objects"), and the preliminary information ("Preliminary Information for Creating Trans Metadevices"), create the trans metadevice with the metainit(1M) command. Refer to the metainit(1M) man page for more information.

Example -- Creating a Trans Metadevice With a Slice for the Master Device

# umount /home1
# metainit d63 -t c0t2d0s2 c2t2d0s1
d63: Trans is setup
(Edit the /etc/vfstab file so that the file system references the trans metadevice 
# umount /home1

Slice /dev/dsk/c0t2d0s2 contains a file system mounted on /home1. The slice to contain the logging device is /dev/dsk/c2t2d0s1. First, the file system is unmounted. The metainit command with the -t option creates the trans metadevice, d63.

Next, the /etc/vfstab file must be edited to change the entry for the file system to reference the trans metadevice. For example, the following line:

/dev/dsk/c0t2d0s2 /dev/rdsk/c0t2d0s2 /home1 ufs 2 yes -

should be changed to:

/dev/md/dsk/d63 /dev/md/rdsk/d63 /home1 ufs 2 yes -

Logging becomes effective for the file system when it is remounted.

On subsequent reboots, instead of checking the file system, fsck(1M) displays a logging message for the trans metadevice:

# reboot
...
/dev/md/rdsk/d63: is logging

Example -- Creating a Trans Metadevice With a Stripe for the Master Device

# umount /home2
# metainit d40 -t d2 c1t2d0s0
d40: Trans is setup
(Edit the /etc/vfstab file so that the file system references the trans metadevice)
# mount /home2

Stripe d2 contains a file system mounted on /home2. The slice to contain the logging device is /dev/dsk/c1t2d0s0. First, the file system is unmounted. The metainit command with the -t option creates the trans metadevice, d40.

Next, the /etc/vfstab file must be edited to change the entry for the file system to reference the trans metadevice. For example, the following line:

/dev/md/dsk/d2 /dev/md/rdsk/d2 /home2 ufs 2 yes -

should be changed to:

/dev/md/dsk/d40 /dev/md/rdsk/d40 /home2 ufs 2 yes -

Logging becomes effective for the file system when it is remounted.

On subsequent reboots, instead of checking the file system, fsck(1M) displays a logging message for the metadevice:

# reboot
...
/dev/md/rdsk/d40: is logging