I've been testing mirroring root partitions for the past few days within a virtual environment and on an old ML350. However, the live system that this is practice for has two disks, and they're non-identical.
I've done a bit of searching through the forum and see that a lot of people recommend just calculating the partitions for the second disk manually. However, I'm a bit of a noob when it comes to doing so, so was wondering if somebody could offer any advice/help.
Here are the two partition tables as they are at the moment:
Disk 1 (i.e. the live disk):
bash-3.00# prtvtoc /dev/rdsk/c1t0d0s2
* /dev/rdsk/c1t0d0s2 partition map
*
* Dimensions:
* 512 bytes/sector
* 63 sectors/track
* 255 tracks/cylinder
* 16065 sectors/cylinder
* 8940 cylinders
* 8938 accessible cylinders
*
* Flags:
* 1: unmountable
* 10: read-only
*
* Unallocated space:
* First Sector Last
* Sector Count Sector
* 143315865 273105 143588969
*
* First Sector Last
* Partition Tag Flags Sector Count Sector Mount Directory
0 2 00 8418060 67119570 75537629 /
1 3 01 16065 8401995 8418059
2 5 00 0 143588970 143588969
3 0 00 75537630 33993540 109531169
6 0 00 109531170 33559785 143090954
7 0 00 143090955 224910 143315864
8 1 01 0 16065 16064
Disk 2 (the soon to be mirror):
bash-3.00# prtvtoc /dev/rdsk/c1t1d0s2
* /dev/rdsk/c1t1d0s2 partition map
*
* Dimensions:
* 512 bytes/sector
* 911 sectors/track
* 2 tracks/cylinder
* 1822 sectors/cylinder
* 13217 cylinders
* 13215 accessible cylinders
*
* Flags:
* 1: unmountable
* 10: read-only
*
* First Sector Last
* Partition Tag Flags Sector Count Sector Mount Directory
0 2 00 1822 262368 264189
1 3 01 264190 262368 526557
2 5 01 0 143487966 143487965
6 4 00 526558 142957764 143484321
8 1 01 0 1822 1821
Notice somebody's failed attempt - ominous!
Firstly - am I right in thinking the disks are (on paper) roughly equal in size (i.e. they share a similar number of sectors, and are both 512bytes/sector)?
Secondly, will prtvtoc/fmthard use the sector positions rather than the cylinder counts when labelling the new disk? Because if so am I right in thinking that the unallocated space on the end of c1t1d0 should mean that a straight copy of the VTOCs between disks is possible? (That is, the current disk's assigned partitions don't overflow past the new disks available sectors?)
Any advice would be greatly appreciated - I can only test so much, and unfortunately this part can only be tested on the live system because I don't have unequal disks to test with 
