Comment # 3 on bug 573488 from fons jongh

Hi Katarina,

Can you fix this bug for all maintained SuSE Linux platforms, please?

If any particular software requires the entry to be in /etc/hosts to resolve
the host name into a loopback address, then that software should be fixed.
Software should be able to verify if the host name or DNS name resolves into a
local address and in such case connect to the loopback address instead the
resolved local address in case that is required.

Not all services listen at 0.0.0.0 (all IP addresses) or at loopback addresses.

Suppose the host name is "myhost" and the host IP address is 192.168.0.1.

You have a service listening at socket 192.168.0.1:8030

/etc/hosts contains the following entries:

# good:
192.168.0.1    myhost.local myhost
# bad:
127.0.0.2    myhost.local myhost

When you want to connect to the local service by host name, the configuration
in /etc/hosts causes the host name to resolve into either 192.168.0.1 or in
127.0.0.2. Because nothing listens at 127.0.0.2:8030, TCP returns a RST upon
receipt of SYN segments to connect to destination 127.0.0.2:8030 and the client
will fail to connect.

Another problem is that if you configure a service to listen at a particular
socket with the host name instead of IP address, then the incorrect entry in
/etc/hosts can cause the service to listen at 127.0.0.2 instead of the host IP
address and clients at remote hosts will not be able to connect.

Of course, we can resolve the problem by removing the entry manually, but this
incorrect configuration causes trouble and it should not be in /etc/hosts.

Thank you very much for your help and kind regards,

Fons