Expanding root partition in Solaris 10 VirtualBox virtual machine

Question

I am running a Solaris 10 u8 x86 64-bit guest as a VirtualBox VM on a WinXP x64 host. I was running out of space in the guest VM, so I used CloneVDI (http://forums.virtualbox.org/viewtopic.php?f=6&t=22422) to clone and expand the VM from 20GB to 30GB. Now I need to expand the / partition in the VM filesystem so that it sees the whole 30GB now available. What is the best way to do this within the Sol10 guest? Is there a way to simply add a new "extent" to the existing filesystem?
Thank you in advance...

Answer 1

sparcmaster wrote:
The virtual disk is now expandable to 40GB.Do you mean you've already expanded it?
prtvtoc /dev/dsk/c0d0s0* /dev/dsk/c0d0s0 partition map
* Dimensions:
* 512 bytes/sector
* 63 sectors/track
* 255 tracks/cylinder
* 16065 sectors/cylinder
* 2717 cylinders
* 2715 accessible cylinders*And here's the problem. The OS didn't care. This VTOC shows only ~20GB
16065 x 2717 / 2 / 1024 / 1024 => 20.81
The only way to change this is to blow it away and recreate it and hope your data survives. If you do it right it should, but you need to be prepared for it to not work.
You'd boot from alternate media (CD/DVD/network), then use 'fdisk' on the root drive. It'll have a 20GB Solaris partition on it. Destroy it and create a new one that is full size (40G).
Now run 'prtvtoc' on the drive again. If the number of sectors per cylinder is the same (just the number of cylinders increased), then you should be okay and able to continue. If the size of a cylinder changed, then your data will probably not be accessible.
Now take your original 'prtvtoc' output file and remove the line with slice 2 in it
* First Sector Last
* Partition Tag Flags Sector Count Sector Mount Directory
0 2 00 6345675 37270800 43616474 /
1 3 01 48195 6297480 6345674
2 5 00 0 43616475 43616474 <=== Remove this line
8 1 01 0 16065 16064
9 9 01 16065 32130 48194Use 'fmthard' to reapply the slices.
# fmthard -s <vtocfile> /dev/rdsk/c0d0s2Check the disk and all the slices should be back.
Verify root filesystem is still present and okay
# fsck -n /dev/rdsk/c0d0s0If all that is done, then you're really close. Since the root slice is at the end of the disk, increasing the size is simple. Just go into 'format -> partition' and edit slice 0. Keep the start cylinder the same, but change the number of cylinders to use the rest of the disk. When done type 'label' and exit format. If done correctly you can now run 'growfs /dev/rdsk/c0d0s0' to increase the size. Reboot and everything should come up.
The worst part is that when you increase the Solaris partition, I don't believe there's a guarantee that the cylinder size won't change. When I've attempted this, I haven't had any problems, but I've always been ready if it didn't work. When it works, it does save time.
Good luck!
Darren