During restoring a file system (that is taken on LVM1) from a Snapshot copy using LVM2, the snapdrive snap restore -fs command does not mount the file system. However, it successfully restores the disk group and host volume associated with it.

For example, the host volume created by LVM1 has a device file in /dev/Mydg_SDDg/Mydg_Sdhv; and the host volume created by LVM2 has a device file in /dev/mapper/Mydg_SdDg-Mydg_Sdhv

This happens because Red Hat Enterprise Linux 4 update 3 hosts use LVM2, which uses a device mapper to interface with the kernel, whereas Red Hat Enterprise Linux 3 update 5 hosts use LVM1, which does not use a device mapper.