On Monday, 10/18/2004 at 03:18 AST, "Froberg, David C" <[EMAIL PROTECTED]> wrote: > Can two network interface be defined with different IP addresses in a Linux > instance (in this case an lpar, SLES 8) with both interfaces using devices > numbers associated with the same OSA-E port?
Yes. It's generically called "multinetting" and predates IEEE VLANs, placing two or more subnets on the same media. It is, however, fraught with peril: - There is no inherent security as is afforded by IEEE VLANs - Multicasts in one subnet will be picked up by the members of the other subnets since multicasts are "subnet-free zones" and are ASSUMED to have scope only within a single subnet. Broadcasts are likewise at risk. - You will have routing problems. If this LPAR will be routing traffic between the two subnets, then it must be primary router (PRIROUTER) on *BOTH* interfaces. By sharing the port, you will not be able to do it. I can envision all sorts of fun with two OSPF or RIPv2 dynamic routers operating this way. Bottom line: It's a Bad Idea and I would have expected your network admins to have beaten you senseless for even thinking it! :-) Alan Altmark Sr. Software Engineer IBM z/VM Development ---------------------------------------------------------------------- For LINUX-390 subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: INFO LINUX-390 or visit http://www.marist.edu/htbin/wlvindex?LINUX-390
