To create a mirror under any of these scenarios

1. Determine the size of the source disk's private region, using one of the following methods:

   • If the source disk is a root disk, obtain its private region length by running the following command:

     # vxprint -l rootdisk

     The disk media name of the root disk is typically rootdisk.

     In the output, find the privlen value. In this example, the value is 3071:

     devinfo: publen=39846240 privlen=3071
     

   • If the source disk is not a root disk, obtain its private region length by running the following command:

     # vxdisk list diskname

     where diskname is the disk media name of the source disk.

     In the displayed output, note the len value for the private field. In this example, the value of this field is 3071:

     private: slice=4 offset=1 len=3071

2. Use the vxdisksetup program to initialize the target disk, Enter the following:

   # /usr/lib/vxvm/bin/vxdisksetup -i c#t#d# privoffset=0 \ 
     privlen=XXXX publen=YYYY

   where XXXX is the size of the source disk's private region, and YYYY is the size of its public region.

   If your system is configured to use enclosure-based naming instead of OS-based naming, replace the c#t#d# name with the enclosure-based name for the disk.

3. Add the newly initialized target disk to the source disk group. Enter the following:

   # vxdg -g diskgroup adddisk medianame=c#t#d#

4. Use the vxdiskadm command and select Mirror volumes on a disk to create the mirror. Specify the disk media names of the source disk (rootdisk) and the target disk (medianame).