On Mon, Jun 16, 2008 at 03:11:35PM -0500, Mike Gerdts wrote: > On Mon, Jun 16, 2008 at 2:50 PM, Nicolas Williams > <[EMAIL PROTECTED]> wrote: > > It doesn't get substantially worse unless the customer adds many entries > > to /etc/services -- but at ~11,000 entries there's not many more that > > they could add, so the time to merge is really bounded at some small > > multiple of 1.5 minutes. > > Oh, but now there are plenty to conflict with.
I don't agree. Two (or more) applications can use the same port numbers with the same or different names, for different protocols, provided they do so on different nodes and that your systems/networks are configured so that never the twain shall meet. There can only be one canonical service name though. > Whenever I've needed a > port for local use I've always grabbed it and not registered it with > IANA. There's a pretty good chance if I've been using it for several > years, the IANA registered use is irrelevant to me. And you still can! > If any upgrade > path tacks my entries onto the end of the file, things like "netstat > -a" will give different output. There's some potential that this may > throw off a variety of homegrown tools that rely upon such output. We may want to ensure that the canonical name of any one port stays the same, post-upgrade, yes. Again, I'm not terribly concerned because OpenSolaris doesn't yet have upgrade semantics, blah, blah, blah. i.services is... not that great. It doesn't do anything about merging service aliases, for example. > Do we have an idea of how often /etc/services is read under various > workloads? If it is really frequently, can you confirm that nscd > caches this to minimize the performance impact of linear file > searches? (I've not kept up on the impact of post S10 nscd changes.) The files backend hashes its sources when it runs in nscd. > Now I am done advocating for the devil. > > If IANA has set aside a range for private use, having that clearly > documented in the services(4) man page and/or comments in > /etc/services file would be a good idea. Good point. Yes, there are private use ports. Nico -- _______________________________________________ networking-discuss mailing list [email protected]
