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Community Member

Continuously Under Attack

I am trying to block this person(s) from hitting my network. Problem is the IP changes from day to day. I see alarms on my sensor and after a Trace Route, confirms this. The only constant is "",

IP ranges from to, tried blocking on my 3500 series router, but that doesn't work because of the IP change. I am tired of seeing this name show up in my alarms,could someone give me an alternative idea on how to "get this person stopped"

The attack is either Nimda or Code Red (II) everytime.This person is not successful, but I still want them gone. ..Help

Community Member

Re: Continuously Under Attack

Robert, try using the hostname instead of the IP address in the access list. Make sure that your name servers configured on the router lists one of the DNS servers his ISP uses.

Community Member

Re: Continuously Under Attack

Or flag it up to RIPE, send them your FW logs and they should be able to see which user has been allocated the IP address, and take it from there.


Community Member

Re: Continuously Under Attack is only SLIGHTLY better at handling abuse reports than and, but you COULD null route their ip off to never-never land. Maybe based on DNS is the way to go.

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