Да, сначала решила, что ддос, но это действительно яндекс его устроил, по IP смотрела. Вот фрагмент из журнала:
5.255.253.21 - - [22/Jul/2016:10:33:13 +0300] "GET /biser_preciosa?filter=2=16;1=6,24,10,9,7;3=18 HTTP/1.0" 508 7375 "-" "Mozilla/5.0 (compatible; YandexBot/3.0; +https://yandex.com/bots)"
141.8.142.52 - - [22/Jul/2016:10:33:13 +0300] "GET /biser_preciosa?filter=3=18,20;1=5,8,3,24,7 HTTP/1.0" 508 7375 "-" "Mozilla/5.0 (compatible; YandexBot/3.0; +https://yandex.com/bots)"
5.255.253.64 - - [22/Jul/2016:10:33:14 +0300] "GET /biser_preciosa?filter=2=16,17;1=8,11,10,24;3=18 HTTP/1.0" 508 7375 "-" "Mozilla/5.0 (compatible; YandexBot/3.0; +https://yandex.com/bots)"
5.255.253.54 - - [22/Jul/2016:10:33:14 +0300] "GET /biser_preciosa?filter=2=16,17;1=23,2,4,7,3 HTTP/1.0" 508 7375 "-" "Mozilla/5.0 (compatible; YandexBot/3.0; +https://yandex.com/bots)"
93.158.152.30 - - [22/Jul/2016:10:33:15 +0300] "GET /biser_preciosa?filter=1=6,8,5,4,11;3=18;2=17 HTTP/1.0" 508 7375 "-" "Mozilla/5.0 (compatible; YandexBot/3.0; +https://yandex.com/bots)"
130.193.51.72 - - [22/Jul/2016:10:33:15 +0300] "GET /biser_preciosa?filter=2=16;1=5,7,10,6,4,3;3=18 HTTP/1.0" 508 7375 "-" "Mozilla/5.0 (compatible; YandexBot/3.0; +https://yandex.com/bots)"
93.158.152.31 - - [22/Jul/2016:10:33:15 +0300] "GET /biser_preciosa?filter=3=22,21,18;1=8,5,3,1 HTTP/1.0" 508 7375 "-" "Mozilla/5.0 (compatible; YandexBot/3.0; +https://yandex.com/bots)"
93.158.152.76 - - [22/Jul/2016:10:33:16 +0300] "GET /biser_preciosa?filter=2=17;1=6,10,3,7,11,23,9 HTTP/1.0" 508 7375 "-" "Mozilla/5.0 (compatible; YandexBot/3.0; +https://yandex.com/bots)"
141.8.142.20 - - [22/Jul/2016:10:33:16 +0300] "GET /biser_preciosa?filter=2=17;1=2,6,7,11,10;3=18 HTTP/1.0" 508 7375 "-" "Mozilla/5.0 (compatible; YandexBot/3.0; +https://yandex.com/bots)"