On Thu, 27 Jul 2000, Allen K. Smith wrote: > I have a three clusters of boxes, all identical hardware except the # of > ethernet cards. Some have 1 (onboard eepro100), some have two, some have > 3 (all eepro 100s). All I want is eth0 to be the same card on all three, > eth1 to be the same on those that have it, and eth2 to be the 3rd. > Consistency is all I'm asking for. > > I'm happy to place the second and third cards in the correct pci slot > order so that they order correctly. I just need the main card (on the > motherboard) to _always_ be eth0. It makes no sense to have it jump > around as I add more NICs. The OS has no way of knowing if a PCI device is on the motherboard, or is in a physical slot. Typically motherboards number the PCI devices so that a plugged-in device is found and used in preference to the on-board device. This is a characteristic of the specific motherboard, and is not specified by any standard. If this causes a problem for your application, select a motherboard that numbers PCI devices differently. Again, this is a hardware attribute, not a software attribute. The Linux kernel provides a mechanism for finding the unique station address for a network adapter. If your user-level code wants to implement a policy of associating a network configuration with a specific network interface, it is a simple matter of programming to save the configuration based on the station address instead of the interface name. ________________ Read /proc/pci. You will find lines such as: Bus 0, device 7, function 0: This means that the device is on the PCI bus 0. Bus 0 is the default top-level bus on a single-bus system. It is at PCI index 7 on that bus. You can think of as virtual slot 7. Each physical slot has a fixed device index. The device index usually increases going away from the CPU. Single function devices are always at function #0. The function index is only used for PCI devices, such as the Symbios SCSI+Ethernet, that have multiple independent functions per chip. Donald Becker becker@scyld.com Scyld Computing Corporation http://www.scyld.com 410 Severn Ave. Suite 210 Beowulf Clusters / Linux Installations Annapolis MD 21403 - : send the line "unsubscribe linux-net" in the body of a message to majordomo@vger.rutgers.edu
