[CentOS] centos 7 database access only possible trough localhost and not IP

Hi there and hello to everybody,

I am all new to centos but I have good experience working with ubuntu and suse. We are moving a an elderly SuSe box to a virtual machine running centos 7. Now I experience the following problem. I can only access postgres using localhost as host. If I use the IP address (even 127.0.0.1). I found a similar problem when accessing the host using http. There I found out (after lots of hair pulling) that I have to set a value using setsebool. So I assume, that I have a similar problem here. I would be grateful, if somebody could point me in the right direction .. thanks robert