Tente usar -v para ter uma saída mais detalhada:
[root@centos7 ~]# mkdir /tmp/test/sourcefolder
[root@centos7 ~]# ls -l /tmp/test
total 0
drwxr-xr-x. 2 root root 6 Feb 21 11:40 sourcefolder
[root@centos7 ~]# ln -v -s /tmp/test/sourcefolder /tmp/test/destinationfolder
‘/tmp/test/destinationfolder’ -> ‘/tmp/test/sourcefolder’
[root@centos7 ~]# ls -l /tmp/test
total 0
lrwxrwxrwx. 1 root root 22 Feb 21 11:55 destinationfolder -> /tmp/test/sourcefolder
drwxr-xr-x. 2 root root 6 Feb 21 11:40 sourcefolder
O loop de link é devido ao comportamento de ln
[root@centos7 ~]# ln -v -s /tmp/test/sourcefolder /tmp/test/destinationfolder
‘/tmp/test/destinationfolder/sourcefolder’ -> ‘/tmp/test/sourcefolder’
[root@centos7 ~]# ls -l /tmp/test
total 0
lrwxrwxrwx. 1 root root 22 Feb 21 11:55 destinationfolder -> /tmp/test/sourcefolder
drwxr-xr-x. 2 root root 25 Feb 21 11:57 sourcefolder
[root@centos7 ~]# ls -l /tmp/test/sourcefolder
total 0
lrwxrwxrwx. 1 root root 22 Feb 21 11:57 sourcefolder -> /tmp/test/sourcefolder
que tenta analisar destinationfolder como um diretório em vez de um symlink já existente.
Você pode evitar isso usando -T:
[root@centos7 ~]# ln -v -T -s /tmp/test/sourcefolder /tmp/test/destinationfolder
‘/tmp/test/destinationfolder’ -> ‘/tmp/test/sourcefolder’
[root@centos7 ~]# ln -v -T -s /tmp/test/sourcefolder /tmp/test/destinationfolder
ln: failed to create symbolic link ‘/tmp/test/destinationfolder’: File exists