Results 1 to 8 of 8
  1. #1
    Join Date
    May 2009

    Angry SYN attack on my server!


    I have a server that is under a huge SYN attack. I keep blocking off the IP addresses that are attacking me, and the next second new IPs keep attacking me again, my firewall keeps banning them every minute but then it comes back.

    What do you guys suggest me to do?

    Your help is appreciated!

    Thank you!

  2. #2
    Join Date
    May 2009
    I already have apf with dos deflate configured on it.

  3. #3
    Join Date
    Mar 2009
    Dallas, Texas
    I would use csf, install dos deflate, and set the number of max connections down low.

  4. #4
    Greetings Adam:

    Your hosting provider tech support should be able to help you in this area.

    Also, if using APF, do make sure you have the latest version with the latest BFD.

    Thank you.
    Peter M. Abraham
    LinkedIn Profile

  5. #5
    Join Date
    Dec 2007
    Indiana, USA
    Depending on the size of the attack (and if they are spoofing) really there's not much you can do to stop the attack other than to simply "deal" with it. If they are hitting a PHP page you may try converting it over to static content until the attack is over to lessen the load on the server and you may want to optimize the site to use as little bandwidth as possible.
    Michael Denney - MDDHosting LLC
    New shared plans for 2016! Check them out!
    Highly Available Shared, Premium, Reseller, and VPS

  6. #6
    Join Date
    Jun 2006
    One thing is to check your sysctl settings and enable SYN cookie protection.

    Otherwise, purchase DDoS protection or a service in a protected DC.
    FiberPeer.Com | | REAL DDoS Protection | Cloud Hosting | VPS | Dedicated Servers | High Bandwidth Hosting | 1Gbps-10Gbps Unmetered
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  7. #7

    If this is the case then you will need to contact to the hosting provider and the tech support engineers working there , they will need to block the traffic from high end. They must be able to help you out with that.

  8. #8
    Join Date
    May 2009
    Thank you for your advise, my tech has helped me on resolving the issue.

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