Got the response from techs:
Hi,
I just got confirmation by the data center that your IP has been nullrouted because of an incoming DDoS attack.
The attack is still going on right now and the IP will be unblocked when the DDoS stops.
Date first seen Duration Proto IP Addr Flows(%) Packets(%) Bytes(%) pps bps bpp
2013-05-09 20:05:00.136 296.821 any 176.56.230.21 9716(81.3) 132.1 M(83.6) 60.0 G(85.6) 444971 1.6 G 454
Kind regards,
George
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I think it is not ddos attack. Actually suddenly we all joined and it's looks like ddos.