Quote:>> >> What I would like to do is to have a 2nd virtual server account with
>> >> another provider - the content of which mirrors that of my primary
>> >> server. Is it possible with DNS to have a lookup performed on the
>> >> hostname www.foo.com look to the IP address of the 1st virtual
>> >> account, and if there is no response (ie. server dead) it goes to the
>> >> IP address of the 2nd virtual account?
...
>> >It is possible and common practice for gateway systems to ahve a name
>> >resolution query reutrn several IP addresses, but if this will result in
>> >the behavior you desire is a question of the browser implementation.
In fact, this works very well with most telnet and ftp programs.
Quote:>> Any idea how I would go about actually configuring something like this
>> though? Is it really to do with the browser anyway or is it lower
Unfortunately, while having several A records in your zone file with different
IP addresses will not break anything, I do not know of _ANY_ major browser
that will try the other addresses if it cannot reach the first address given.
I've noted this lack last year, and the year before- It's been a minor
annoyance for quite some time, though not quite annoying enough for me to
hack it into X-mosaic :)
Quote:>Just put an A record several times into your zone file each time with a
>different IP address assigned.
>On the client side gethostbyname() will return a hostent structure, which
>will contain an array of all the addresses assigned to that name. Now a lot
>of software always just takes the first address and if it doesn't work
>gives up...so it will depend on the browser code.
One thing you can do to distribute the load amongst two or more mirrors is to
use 'round robin' IP addressing, where the DNS server returns the list of
addresses shifted by one each time- so different remote users will get a
different address first, and access a different server. This doesn't gain you
much since the instantaneous hit rate from a single Netscape client grabbing
all the images in parallel has more of a impact than the average hits/second.
by