jc@minya.UUCP (John Chambers) (06/01/90)
In article <9005230215.AA10732@ucbvax.Berkeley.EDU>, 08071TCP@MSU.BITNET (Doug Nelson) writes: > From Stan Stead: > > We are running 4.3 BSD. We currently use nameservice. However, > >a site that we wish to exchange mail and files, while connected to the > >internet, does not use nameservice. We can access the site by internet > >number, but not by name. Is there anyway to "hot-wire" an address > >(perhaps via /etc/hosts). Currently, the only way /etc/hosts is read > >is if named is not running. > > The real answer is for them to set up name service. I can't think of > any good reason for sites attached to the internet to not be running > name service, or to find a site that can run name service for them. Gee, I can think of several reasons off the top of my head. For instance, I'm working in a network testing lab in which we are constantly fiddling with the wiring, setting up new networks for a few hours, interconnecting them at random, changing host names and IP addresses, and all the other things you need to do to test stuff. It's not even vaguely reasonable to expect a nameserver administrator to keep track of all our fiddlings, and usually we only tell them about the couple of "main" machines that hold the source, or where we want to send/receive mail. The rest we take care of by editing /etc/hosts as needed. An example of how difficult things can be is our couple of DOS machines with tcp/ip. They don't have a local hosts file, and must get all addresses from a nameserver. The result is that tests on DOS are *much* slower, since we must go through a nameserver, which means telnetting to the nameserver, editing files, and all that. Another nameserver gotcha turned up a couple of months ago, when people decided to rename and renumber all of the "main" machines in the lab. The nameserver had the wrong IP address (two digits interchanged) for the mainest of the machines (the one with all the source on it), and it took about a month to persuade the (badly overworked) administrator of the nameserver to correct the typo. /etc/hosts came in very handy during this period. Yeah, I know, these are all pathological cases that "shouldn't happen" to many users. My main response to that sort of criticism is that I've never yet worked on a machine that wasn't unusual in some major respect. (I keep looking for one; I assume they must exist somewhere... ;-) If you want to get your job done, you often have to find ways around all the broken software, and nameservers are often broken with respect to some subset of the machines on the network. So you use it if you can, and learn to live without it when you must. -- John Chambers ...!{harvard,ima,mit-eddie}!minya!jc -- If you're not part of the solution, you're part of the precipitate. [Kiel oni ^ci tiun diras esperante?]
del@thrush.mlb.semi.harris.com (Don Lewis) (06/01/90)
In article <386@minya.UUCP> jc@minya.UUCP (John Chambers) writes: >In article <9005230215.AA10732@ucbvax.Berkeley.EDU>, 08071TCP@MSU.BITNET (Doug Nelson) writes: >> From Stan Stead: >> > We are running 4.3 BSD. We currently use nameservice. However, >> >a site that we wish to exchange mail and files, while connected to the >> >internet, does not use nameservice. We can access the site by internet >> >number, but not by name. Is there anyway to "hot-wire" an address >> >(perhaps via /etc/hosts). Currently, the only way /etc/hosts is read >> >is if named is not running. >> >> The real answer is for them to set up name service. I can't think of >> any good reason for sites attached to the internet to not be running >> name service, or to find a site that can run name service for them. > >Gee, I can think of several reasons off the top of my head. For instance, >I'm working in a network testing lab in which we are constantly fiddling >with the wiring, setting up new networks for a few hours, interconnecting >them at random, changing host names and IP addresses, and all the other >things you need to do to test stuff. It's not even vaguely reasonable >to expect a nameserver administrator to keep track of all our fiddlings, >and usually we only tell them about the couple of "main" machines that >hold the source, or where we want to send/receive mail. The rest we take >care of by editing /etc/hosts as needed. You could just create a "lab" subdomain and designate one of your local machines as the server. That way you don't have to bother your overworked nameserver administrator (and you contain the damage). Editing the zone files isn't that much harder than editing /etc/hosts, and you don't have the bother of having to propagate the /etc/hosts around, or do you just just use IP addresses everywhere. > >Another nameserver gotcha turned up a couple of months ago, when people >decided to rename and renumber all of the "main" machines in the lab. >The nameserver had the wrong IP address (two digits interchanged) for >the mainest of the machines (the one with all the source on it), and >it took about a month to persuade the (badly overworked) administrator >of the nameserver to correct the typo. /etc/hosts came in very handy >during this period. Well, what if you sent your new (incorrect) /etc/hosts out all your friends on the internet. How much of a bother would it be to them to have to incorporate this into their /etc/hosts files, and then turn around and correct it. And how much time is someone who missed the correction (and someone at your end) going to spend debugging the problem a six months from now when mail won't go through. -- Don "Truck" Lewis Harris Semiconductor Internet: del@mlb.semi.harris.com PO Box 883 MS 62A-028 Phone: (407) 729-5205 Melbourne, FL 32901