I never gave netconfig any IP. It does not ask for an IP. Honestly, I do not know where 192.168.0.101 came from. I edited /etc/hosts and put

192.168.0.1 SERVER_HOST.DN1 SERVER_HOST

After I booted, this line disappeared. [But I think 0.1 is reserved. Perhaps I should have write 192.168.0.2] Well, I think I'll continue studying networks before I go on with this after all.

Something remarkable happened. I put the line

192.168.0.101 .........

not in the server's /etc/hosts but in the local host's. As a result, when I issued 'slogin SERVER_HOST' from the local host, I was asked for the password. So I had it all wrong!

If netconfig didn't ask for an IP adress, it's probably because you selected DHCP (or maybe networkmanager, I don't know how that one works). In that case SERVER_HOST would ask the router (whose ip probably is 192.168.0.1) for an ip, and SERVER_HOST would be given 192.168.0.101.

Putting "192.168.0.101 SERVER_HOST.DN1 SERVER_HOST" in /etc/hosts at "local host" basically tells "local host" that "whenever I want to talk to SERVER_HOST or SERVER_HOST.DN1 I should address my messages to 192.168.0.101." So that `slogin SERVER_HOST` works after this change was to be expected.
However if you're using DHCP there is no guaranty that SERVER_HOST always will have 192.168.0.101 as its ip.

There was a small discussion some time ago on the merits of static ip + /etc/hosts versus dhcp, might be of interest to you: http://www.linuxquestions.org/questi...ip-4175436549/

I use DHCP because my ISP does not provide static IPs (I think). As to the rest, logging remotely from the server works fine, but doing it from the local host, the system asks for the password, OK, but then it says 'Permission denied. Please try again'.

Yes, I selected DHCP.

Well, it's only the router/modem that talks directly to your ISP (if I've understood your network correctly). The 192.168.0.x addresses are only visible to your computers, and can be set statically (if that is deemed to be desired).

As to the Permission denied, do you have a user with the same user name on SERVER_HOST as the user who is running `slogin SERVER_HOST` on "local host"? (If the user is root, maybe you have disable remote root logins (as you probably should), PermitRootLogin in /etc/ssh/sshd_config? Do you have any entries in /etc/hosts.deny?
/var/log/messages (or /var/log/syslog) on SERVER_HOST might have some information.

When at the local host, I was always as root. Now I tried going to a console (virtual console in the same machine, the local host) where I am a regular user. I ran 'slogin SERVER_HOST' and this time I succeeded. In the server, in the file /etc/ssh/sshd_config I have

PermitRootLogin no

So there, in the local host, I can only remote login if I am a regular user. However from the server I can remotely login (into the local host) as root! So there is no symmetry. One of the machines is boss.