Linking to numeric IP addresses vs. alpha in URLS

[Stacy Pober]

At our library we have several databases (our catalog and some 
periodical databases) supplied over an Extranet connection.  The 
Extranet is intended to provide better performance and more stability 
in our connection to these sites.  The problem is, when the Extranet is 
up and the campus Internet connection is down, we aren't always able to 
access the Extranet sites.  This is supposedly due to DNS failure 
as there is no DNS server on the Extranet and our local DNS server does 
not cache addresses.   (I say 'supposedly' because one of those sites 
does not allow ping or tracert connections from the Extranet sites, and 
the failure message isn't one that indicates DNS problems per se.)

I was considering switching the alphabetic domain name with the numeric 
IP addresses in our links to these sites, but according to tech support 
at one of the vendors, they don't think this is a good idea, since 
they may switch servers (and thus numeric IP's) at times.  Since we 
just went through a period of several days when we were unable to 
access one of these services, I was considering providing a backup link 
with a numeric IP for just these times, as in:

<A href="http://vendor.com/search.html">database</a><br>
<a href="http://123.123.123.1/search.html">alternate link for 
database</a>

Has anyone done something like this?  The idea of providing backup 
links just seems a little clunky - is there a more elegant solution? 
Is there a way to save the DNS information for these sites locally, so 
we wouldn't run into this problem?  According to the campus computing
folks, the campus DNS server does not cache address information, so  
"locally" would be at the brower or PC  level, not at the DNS server.

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Stacy Pober                   mailto: spober at manhattan.edu
Information Alchemist         http://www.manhattan.edu/library/
Manhattan College Libraries   Voice: 718-862-7166
Riverdale, NY 10471           Fax:   718-862-7995
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