Thanks to all who've helped so far. Here are a few further details.
Christian Eisendle wrote:
> In case of a slow network, the DNS-Server could be the reason for this
>problem, but after a refresh of the site (or maybe restart of the
>browser) the website should be opened.
>Are there any virtual hosts on the webserver? If not, users having
>this problem could try to enter the IP-Adress of your webserver
>instead of the DNS-Name, to determine if the name-resolving makes the
Indeed, some users who couldn't use the name can now access the server
with the IP-Adress. From this I conclude that the problem must
definitely be with the DNS-Server, or with network speed.
The web server is registered with the central university administration,
and they've told me it is entered correctly in their DNS server.
I can't readily compare nslookup output from outside the university and
inside because I'm inside the university network even if I connect from
home, but I'll try to get someone to do that for me.
As for the samba problem:
>What's the exact problem? Is it a connection or an authenticating
>problem? At first try to connect with the ip-adress instead of the
>netbios name (\\222.222.222.x\share)
>Does a telnet to samba server on port 139 work?
>Does it work, when SuSEfirewall2 is stopped?
1) Connection with IP-Address works.
2) telnet is disabled on the server. an ssh connection on that port
3) the connection works without the firewall, even with the server name,
and not only with the ip address. with the firewall, it only works with
the ip address.
The firewall configuration file now looks like this:
FW_SERVICES_EXT_TCP="22 80 ssh www"
This is my smb.conf:
workgroup = ISTB
netbios name = ISTB server
server string = ISTB fileserver on %h
encrypt passwords = yes
invalid users = root
hosts allow = 188.8.131.52/25 localhost
load printers = no
passdb backend = smbpasswd:/etc/samba/smbpasswd
comment = ISTB Kollektivverzeichnis
volume = ISTB-Kollektiv
path = /istb_userdata
browseable = yes
writeable = yes
guest ok = no
valid users = istb_user
read list = istb_user
write list = istb_user