Create a directory where you'll mount the new disk, for example /new-disk, and mount it there:
mkdir /new-disk mount -t ext2 /dev/hdb1 /new-disk
If the new disk will have more than one Linux partition, mount them all under /new-disk with the same organization they'll have later.
Example. The new disk will have four Linux partitions, as follows:
/dev/hdb1: / /dev/hdb2: /home /dev/hdb3: /var /dev/hdb4: /var/spool
Mount the four partitions under /new-disk as follows:
/dev/hdb1: /new-disk /dev/hdb2: /new-disk/home /dev/hdb3: /new-disk/var /dev/hdb4: /new-disk/var/spool
You must create the mount points for each level before you mount the partitions at that level.
mkdir /new-disk [1st level] mount -t ext2 /dev/hdb1 /new-disk mkdir /new-disk/home [2nd level] mount -t ext2 /dev/hdb2 /new-disk/home mkdir /new-disk/var [2nd level also] mount -t ext2 /dev/hdb3 /new-disk/var mkdir /new-disk/var/spool [3rd level] mount -t ext2 /dev/hdb4 /new-disk/var/spool
If you've created a mount point at /new-disk/tmp, you'll need to correct the directory's permissions to let all users access it:
chmod 1777 /new-disk/tmp