Re: good practice for clients
| For those who don't follow uk newsgroups, this comes after some heated
| discussion, where I was trying to encourage users of caches to accept
| the fact that they were at least partly to blame in the case where
| their WWW access was interrupted by their browser's inability to
| degrade gracefully in the light of a proxy failure.
Well, you did kind of imply that everyone ought to be running Netscape >
= v2 ! <ducks>
| > [ + detect and act appropriately when servers have multiple IP
| > addresses ? Problems with DNS resolver code here ? ]
| I don't know why this is in brackets. What's stopping resilient clients
| being written now (other than nscd of course), what problems do you
| anticipate in the DNS resolver code?
Yep - cheers, Sun!
One particular problem I've seen here and there is with resolvers only
returning a single IP address even though there are several associated
with the DNS entry. Caching DNS lookups for the duration of the
session (e.g. while DOS TSR loaded), even if the address(es) stop
working, can also be a bit of a bugger.
I may be being pointing the finger at the wrong culprit here, though -
perhaps it's the browser or the TCP/IP implementation which isn't doing
anything with those multiple IP addresses, and they are all being
returned by the DNS lookup ?
There isn't the time or the inclination for me to go around checking
the innards of all these wretched Mac/M$ setups (unless someone is
offering to make it worth my while :-), but a little light testing
suggests that we at least have a problem in this department. I suspect
others do too. Any corroborating evidence ?
| >Does the above sound reasonable as a baseline ? I realise that this
| >stuff isn't universally supported, but that's another story!
| I find it unbelievable that it isn't universally supported.
Yep - in-lined infomercials must be a higher priority!
From my experiences hacking at the X Mosaic proxy support (feel sorry
for the NCSA guys, I'm a pretty lame programmer) it's certainly not a
big deal. But... lots of people are working with code which is only
expecting a single proxy, or if you're lucky maybe one proxy per
protocol and no fallbacks ?
PS I think it would be quite useful if the CERN server were capable of
surviving the outer proxy's death automatically, e.g. by using other
proxies and/or direct connections. Before I get out my lame
programmer's hacking kit, does anyone have patches to make it do this ?
Haven't come across any...