drwxr-xr-x 4 root root 4096 May 25 09:44 .
drwxr-xr-x 18 root root 4096 May 25 09:46 ..
lrwxrwxrwx 1 root root 9 May 25 09:44 sd -> /mnt/sda1
drwxr-xr-x 2 root root 4096 May 25 17:32 sda1
drwxr-xr-x 3 root root 4096 May 25 09:22 sda2
sd -> /mnt/sda1
is symbolic link, you could safely delete it and recreate it as way you like.
ln -s /path-text/of-symbolic-link /path/to/file-to-hold-that-text
rm /mnt/sd
ln -s /mnt/sd /mnt/sda2