How to Create a Trans Metadevice for a File System That Cannot Be Unmounted (Command Line)

After checking the prerequisites ("Prerequisites for Creating DiskSuite Objects"), and the preliminary information ("Preliminary Information for Creating Trans Metadevices"), use this procedure to log a file system, such as /usr, that cannot be unmounted during normal system operation. Refer to the metainit(1M) man page for more information.

Example -- Creating a Trans Metadevice for /usr

# metainit -f d20 -t c0t3d0s6 c1t2d0s1
d20: Trans is setup
(Edit the /etc/vfstab file so that the file system references the trans metadevice)
# reboot

Slice /dev/dsk/c0t3d0s6 contains the /usr file system. The slice to contain the logging device is /dev/dsk/c1t2d0s1. Because /usr cannot be unmounted, the metainit command is run with the -f option to force the creation of the trans device, d20. Next, the line in the /etc/vfstab file that mounts the file system must be changed to reference the trans metadevice. For example, the following line:

/dev/dsk/c0t3d0s6 /dev/rdsk/c0t3d0s6 /usr ufs 1 no -

should be changed to:

/dev/md/dsk/d20 /dev/md/rdsk/d20 /usr ufs 1 no -

Logging becomes effective for the file system when the system is rebooted.