Yahoo! clue (Slightly OT: Spiders)

Kradorex Xeron admin at
Thu Mar 29 14:17:50 UTC 2007

On Thursday 29 March 2007 09:15, Valdis.Kletnieks at wrote:
> On Thu, 29 Mar 2007 09:05:12 EDT, Kradorex Xeron said:
> > Slightly OT: Does anyone know what is with the web spiders from
> > Yahoo/Inktomi? I've been seeing reports and have seen a problem with them
> > opening 10 to 100 connections to any specific site.
> And 10 concurrent connections (or 100) causes a production-quality
> webserver difficulties, how, exactly?

True - however: 

It may cause certain sites to go over quota for transfer (even if you do rate 
limit them via robots.txt). As well as it could cause servers that limit 
to "x number of connections at once" (i.e. some public file hosting servers 
that don't alow more than x users at once) to lock out legitamate requests - 
which if you per-se don't control the robots.txt of such sites, you would be 
unable to get access that site.

Another problem is that the Yahoo/Inktomi search robots do not stop if no site 
is present at that address, Thus, someone could register a DNS name and have 
a site set on it temporarily,  just enough time for Yahoo/Inktomi's bots to 
notice it, then redirect it thereafter to any internet host's address and the 
bots would proceed to that host and access them over and over in succession, 
wasting bandwidth of both the user end (Which in most cases is being 
monitored and is limited, sometimes highly by the ISP), and the bot's end 
wasted time that could have been used spidering other sites. 

People shouldn't need to protect themselves from search engine bots, The 
Internet already has enough problems as it is with Spam and Botnets among 
other items, Search engine bots with large pipes don't need to be on that 
list of nuicences as well.

But that aside, from what I've seen, no other search engine takes that 
aggressively toword sites. -- I was just curious as to why Yahoo/Inktomi's 
bots are so aggressive (Even more than Google, MSN and such), I reviewed 
their site's reason, however, the others do review millions/billions as well.

Apologies if my postings are unclear.

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