Paul, I'm having a bit of difficulty "getting my head round" what you may have had in mind with the name server solution. Routers have no interest in names they just get on with their job of routing IP packets. What they will "propagate" is the data required to maintain their and neighbouring routing tables if they are implementing a dynamic routing protocol - which, again, they "should".
Maybe what you had in mind initially is that, in an ideal scenario, John could persuade existing clients to access the mainframe by name and, when all had done so, change the address on the mainframe and in the name server. What do you mean by "the lesson"? If you have a NAT box in between you and "the rest", whether "the rest" is the Internet or an intranet, you can happily use any addresses you like - although RFC 1918 addresses are recommended. My PC is on its own intranet with a little black box ADSL router on the floor. The router interface address is 192.168.1.1, my PC interface address is 192.168.1.2 and my daughter's laptop interface address is 192.168.1.5. The router's "web site" - and my name server handshaking program - tell me that the address I use in the wide, wide world of the Internet is - currently - 80.2x0.140.74 (obviously slightly disguised). Chris Mason ----- Original Message ----- From: "Paul Gilmartin" <[EMAIL PROTECTED]> Newsgroups: bit.listserv.ibm-main To: <IBM-MAIN@BAMA.UA.EDU> Sent: Wednesday, 22 February, 2006 5:46 AM Subject: Re: TCP/IP over Cisco router CIP (also DHCP, Flex-ES, Hercules) > In a recent note, John S. Giltner, Jr. said: > > > Date: Tue, 21 Feb 2006 22:51:01 -0500 > > > > Neal Eckhardt wrote: > > > > > > When our network was upgraded many years ago, the consultant made the > > > unfortunate decision of putting the mainframe on it's own network at > > > address 192.168.1.1 and as we all know, that address conflicts with > > > just about every router out there. The time has come to remedy that > > > situation. > > > > And someone actually paid him for this advice? > > > > The least disruptive solution would be to have the ability to support > > > two IP addresses to the mainframe so the changeover could be phased > > > in, instead of having a "drop dead" time where everything has to > > > change. > > > > Domain name servers are wonderful things. Everyone should use one. > Or several. But I still won't recommend that you ease the transition > by temporarily registering the domain of your mainframe as 192.168.1.1. > (Routers won't propagate it, will they?) Every now and again our > network admins do a reconfiguration that requires changing the IP > addresses of our mainframes. With DNS, it's painless. > > Using hard coded IP addresses is a blunder akin to misusing > self-defining terms in assembler code. > > The lesson for anyone planning to be in your circumstance (or > hoping to avoid it) is to get a real IP address assigned whether > you need it or not. > > But this provokes a question: if someone walks into an internet > cafe with his laptop running z/OS under Flex-ES or MVS 3.8 > under Hercules, can he exploit DHCP to assign a local IP > address for the OS system? And can an OSA be emulated using > an 802.11g card? > > -- gil > -- > StorageTek > INFORMATION made POWERFUL ---------------------------------------------------------------------- For IBM-MAIN subscribe / signoff / archive access instructions, send email to [EMAIL PROTECTED] with the message: GET IBM-MAIN INFO Search the archives at http://bama.ua.edu/archives/ibm-main.html
