>On Sun, 04 Jan 2004, Dmitry wrote: >> Lets say I have a 3giger and and a 60giger. >> I join them using LVM into one logical partition. Lets say the 3 giger >> fails, do I have any hope recovering what resides on the 60 giger part >> of the logical partition? The 3GB hard drive is well beyond its warranty period by now and could fail at any moment; it could be fine for many years to come, but is it really worth the risk to increase total LVM space from 60GB to 63GB? In my opinion, the 3GB hard drive is too small to be used effectively with the 60GB hard drive in forming logical volumes. How important is it to have a 63GB logical volume versus a 60GB logical volume? Micah Anderson wrote: >You have some hope, but not much. You would have a lot of hope if you >created a RAID mirror (I suggest software raid) and then used those >resultant devices to create your giggers. A RAID 1 mirror of a 3GB and 60GB drive would be 3G in size and "waste" 57GB of the 60GB drive. It's not practical to construct a RAID 1 of two drives whose capacity differs so greatly, especially when the smaller drive is only 3GB in size and 1/20 the size of the larger drive. Maybe the 60GB drive could be split into 20 3GB partitions and made to appear as 20 3GB hard drives. These 20 virtual 3GB hard drives and the real 3GB hard drive could form a 21 hard drive RAID 5 with a total of 60GB of usable space. However, performance would probably be bad, since there are only 2 hard drive actuators rather than 21. LVM striping would obviously perform badly for the same reason on this setup. LVM can only perform as well as the physical volumes in the volume group. BTW, I'm not seriously suggesting such a RAID 5 setup for production use. Sincerely, Ken Fuchs <kfuchs@winternet.com> _______________________________________________ linux-lvm mailing list linux-lvm@sistina.com http://lists.sistina.com/mailman/listinfo/linux-lvm read the LVM HOW-TO at http://tldp.org/HOWTO/LVM-HOWTO/
