Mikus Grinbergs wrote: >> 7. Holt will SHIP 12 USB-to-Ethernet dongles from Boston to Sri Lanka. >> > > I have extensive experience at using Ethernet. Please don't hesitate to > ask me if you have questions. > > > In the meantime, some things to keep in mind: > > * The XOs expect a name server to be available on that Ethernet (to > give out dynamic IPv4 addresses). The Ethernet ought to also have an > NTP server on it. >
Nomenclature problem: Dynamic IPv4 addresses are given out by a DHCP server, not a name server. Name servers (also known as "DNS servers") translate textual names like "dev.laptop.org" into numeric IP addresses; they have nothing at all to do with the assignment of dynamic IPv4 addresses. The symptom of a DHCP server problem is that machine cannot obtain an IP address for itself - attempts to "bring up" the network interface will pause for a long time and eventually time out. The symptom of a name server problem is that the machine, after the interface has already been brought up successfully, does not recognize the names of machines on the outside Internet - you get messages like "unknown host" from commands like "ping". In some networks, the DHCP server program and the name server program happen to be running on the same machine - a computer or a router box. But that is not at all necessary; they could be running on different machines in wildly different locations. The DHCP server must be local - on the same Ethernet to as Mikus puts it - so your machine can reach it by broadcasting, but the name server may be halfway around the world. > [I myself have not yet tried running the Ethernet with IPv6 addresses.] > > * When you first install any XO (or first-boot any new build on that > XO), do it without having the dongle plugged in at the XO. You can plug > the Ethernet connection in once you see any Sugar screen. > > What this does is assign the Ethernet device *after* the radio device > has been assigned. It turns out Ethernet control does not work well if > 'eth0' had been assigned to the Ethernet device. [ You can check that > Ethernet is on 'eth1' in /etc/udev/rules.d/70-persistent-net.rules ] > > It helps if you keep the SAME Ethernet dongle with each individual XO. > Each time you use a different dongle, Network Manager assigns a > different interface name -- that can quickly get confusing. > > * The Network Manager could randomly step in and assign a zeroconf IP > address to a working Ethernet interface (thereby taking the previously > existing connection down). > > I actually wrote a tiny batch script that I invoke manually. It issues > the 'ifconfig' and 'route' commands to re-establish Ethernet connection. > > * If you boot and Ethernet is not working, issue 'ifconfig' and look > for the (usually 'eth1') interface assigned to the Ethernet. Network > Manager is what assigns that interface - so it needs to be running. A > good way to "kick" the Ethernet connection into life (when the XO is > running but the Ethernet isn't) is to unplug the Ethernet cable from the > dongle, wait five or more seconds, then plug the cable back in again. > > * Attempts to assign a static IPv4 Ethernet address to an XO > may/may_not work. Tread carefully. > > * Treat the Ethernet icon in Frame more as an indicator than as a > control over the Ethernet connection itself. Instead: to start > Ethernet, plug in the cable; to stop Ethernet, pull out the cable. > > > mikus > > _______________________________________________ > Testing mailing list > [email protected] > http://lists.laptop.org/listinfo/testing > _______________________________________________ Testing mailing list [email protected] http://lists.laptop.org/listinfo/testing
