Make sure your router's DHCP server functionality is disabled. On Wed, Aug 14, 2019, 15:13 D. R. Evans <doc.ev...@gmail.com> wrote:
> 1. I have a server that does all I need it to do under stretch. > > 2. On that machine, I have installed a clean version of buster on a > separate > bootable drive. > > 3. Under buster on that machine, I have installed (by copy from stretch) an > iptables configuration that seems to be behaving as I expect. In > particular, > it allows me to reach the Internet from machines on the LAN side of the > server. > > 4. Under buster, I have installed isc-dhcp-server and copied a working > /etc/dhcp/dhcpd.conf from stretch. It seems to be behaving correctly. In > particular, it seems to be responding correctly to machines on the LAN > side of > the server. > > 5. If I ping by name a machine on the Internet from the server (e.g., > google.com), the ping succeeds. > > 5. If I now go to another machine on the LAN and ping a machine on the > Internet by address (e.g., 172.217.11.238), the ping succeeds. > > 6. But if (still on another machine on the LAN) I ping a machine on the > Internet by name, (e.g., google.com) the request times out and I receive > the > message: "ping: google.com: Name or service not known". > > 7. On the machine on the LAN, if I look at the configuration for the port > on > the LAN machine (using nmcli), I see: > IP4.DNS[1]: 192.168.0.1 > which is correct (the server's IP address being 192.168.0.1). > > So this seems to be saying that: > 1) the basic packet forwarding through the server is working > 2) DNS on the server itself is working > 3) DNS requests received from the LAN by the server are not being > resolved > > I would appreciate any suggestions as to how to diagnose and fix the > problem. > > Doc > > -- > Web: http://enginehousebooks.com/drevans > >
