[Frank Weißer] > the dhcp server on gateway (FRITZ!Box 7490) was definitely stopped > before installation and stayed so. I installed from the netinstall image > by entering network configuration manually when the automatic > configuration failed due to missing dhcp server. That's the problem; why > are urls resolved during installation but not after it?
Perhaps your ISP block direct DNS lookups, so you need to tell the main server DNS to forward its lookups via your ISPs server, ref If generic DNS traffic is blocked out of your network and you need to use some specific DNS server to look up internet hosts, you need to tell the DNS server to use this server as its "forwarder". Update /etc/bind/named.conf.options and specify the IP address of the DNS server to use. in <URL:https://wiki.debian.org/DebianEdu/Documentation/Buster/GettingStarted >. Perhaps you can extend the text to make it easier to discover for the next reader? -- Happy hacking Petter Reinholdtsen