[ic] Spiders gone berserk?

[DB]

Recently I've been seeing many sessions from single IPs but not always 
the same one. See below for an example output of my "current session" 
display from the admin interface. The one I see lots of right now has 
nslookup from "askfast.com" which sounds like a search engine.

All these sessions seem excessive and I can block the IP, but I don't 
want to stop search engines from crawling my site. On the other hand it 
goes on for hours and all this eats bandwidth and CPU time. Have other 
seen such behavior?

DB


---- Example "current sesssions" ----

      yos8GHYr:66.77.73.68
xbmEaHuz:66.77.73.68
xSLK8z9B:66.77.73.68
vg35VaCn:66.77.73.68
v8EX95Ln:66.77.73.68
uz4ozNtn:66.77.73.68
uqRqrAqg:66.77.73.68
uYaY5F5V:66.77.73.68
uX3EcZRu:66.77.73.68
tuQbcyaD:66.77.73.68
tM8cy9Gj:66.77.73.68
tGmRSz8T:66.77.73.68
sgXhzRfH:66.77.73.68
sGLFBSvx:66.77.73.68
sABcFU4I:66.77.73.68
rdvuDwFW:66.77.73.68
qNsLa78E:66.77.73.68
qLzh9QDF:66.77.73.68
pcxN6euk:66.77.73.68
pJMerTf7:66.77.73.68
pJLGPIv9:66.77.73.68
pHUtHax8:66.77.73.68
p3CJhxsI:66.77.73.68
obm8npYH:66.77.73.68
oEhtsYVG:152.163.188.3
nY7b6wXu:66.77.73.68
n2IYneAn:66.77.73.68
mdqh3ZWt:66.77.73.68
mLbBfAdG:66.77.73.68
jGuVQx9g:66.77.73.68
iim6zW6C:66.77.73.68
i3bH86bx:66.77.73.68
gpo6ipHo:192.249.47.11
gQ4Rc8Kf:202.166.126.228
fzLiYXqn:66.77.73.68
evyA86wD:64.144.71.115
esfYpuHi:66.77.73.68
eavrK7FR:66.77.73.68
e2rBx9Xf:64.12.96.74
dxP8CavI:205.188.209.173
doiwktEz:207.140.66.1
cxxJ4Roa:66.77.73.68
cwjWw25c:66.77.73.68
cqL98XHL:66.77.73.68
cjv52hhX:199.0.73.195
cHBkX2J2:66.77.73.68
cC2Twdf7:66.77.73.68
c5iJ8Nse:66.77.73.68
buyAWCkc:66.77.73.68
bhoxPIGx:66.77.73.68
bIqxz2W6:12.31.5.69
b5zF22ES:66.77.73.68
ajzYYwmY:66.77.73.68
Zh5hFjVM:66.77.73.68
Zg4tGMFB:66.77.73.68
YqdavSgH:66.77.73.68
Y6sNAJwf:66.77.73.68
Y3PWRUw3:66.77.73.68
XzbtEWvs:66.77.73.68
Wpunp3we:66.77.73.68
WQWhXQnf:165.138.103.249
WNdJkQvU:66.77.73.68
VzbRtu8P:66.77.73.68
VVu3nImC:65.214.36.150
V4eZnGHR:66.77.73.68
Uut4Ngg8:66.77.73.68
UehmXdFM:66.77.73.68
Swr98kdR:66.77.73.68
SXJ2GxHT:66.77.73.68
SUCrfzBr:163.234.146.253
STCBo3zw:66.77.73.68
SKK62hxz:66.77.73.68
RibuXhZr:66.77.73.68
RZanz5vL:66.77.73.68
RUNqH2CG:66.77.73.68
RHFvAzgy:66.77.73.68
Qrkjr8hg:209.240.198.63
QPxbt2eE:66.77.73.68
QIt2Qqd3:216.124.136.4
Peytw4H6:66.77.73.68
P9JPST5T:66.77.73.68
NoV56iZt:66.77.73.68
NKvGheNR:66.77.73.68
LvcEKXtj:66.77.73.68
LjWnPVuH:152.163.189.234
LMZF7ZDU:66.77.73.68
LKDNj2VH:66.77.73.68
LB5zzCT9:66.77.73.68
KRashLQ9:66.77.73.68
KRwQKvwC:66.77.73.68
JhdHyXc3:66.77.73.68
JXpxzCMf:66.150.40.75
IxmLRvE6:66.77.73.68
IbekIFwL:66.77.73.68
ISxKkmXL:66.77.73.68
H6SVH4Nk:66.77.73.68
Fosd6i9z:66.77.73.68
Far9Nce6:66.77.73.68
FUNYi39j:66.77.73.68
FPAesjbT:66.77.73.68
FLnorqin:66.77.73.68
F8iuosHR:64.144.71.115
F3hk3q2H:66.77.73.68
EHj9dgBU:66.77.73.68
DqgDYE2s:163.234.146.253
DcoF4JgQ:66.77.73.68
DYR4vnqg:66.77.73.68
DNEVG4vd:66.77.73.68
DMKjChUX:207.140.66.1
DEj6rWao:66.77.73.68
DAnd5Xcz:64.105.84.182
CzQIPko2:152.163.201.204
CoNF3mco:66.77.73.68
CVVWqdJH:66.77.73.68
C9NoqSQU:66.77.73.68
C3By3zDr:152.163.189.236
BymemTfX:66.77.73.68
BQ8dJ3yh:66.77.73.68
BNrnEvdF:66.77.73.68
A3Q3jJQQ:66.77.73.68
9unF8vys:66.77.73.68
9pskNn3K:66.77.73.68
9ncJXWMn:66.77.73.68
9XRspVnA:208.133.55.62
9VDEQ4qC:66.77.73.68
9Me8ikMB:66.77.73.68
8oCaMQSW:66.77.73.68
8hyVM4XP:66.77.73.68
82wiTkeK:66.77.73.68
7izL7G7i:66.77.73.68
7FHkjfr5:66.77.73.68
7A47WzZz:66.77.73.68
6KrYVn6f:66.77.73.68
5LYgiePW:66.77.73.68
4p43TkGj:66.77.73.68
4d3czThp:66.77.73.68
3o5RqUtj:207.140.66.1
3giD8Hmm:66.77.73.68
3RPjRB9Y:207.140.66.1
2s6JAdt6:66.77.73.68
2WfaQuhj:12.154.5.254
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