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how to prevent DDoS attacks ?

Solved Vulnerability
34 2 13.8k 1
  • wrote on last edited by
    #7

    @phenomlab yes, we were checking here yesterday, but we have seen comments about disabled ufw after doing this… so, we have skipped it…

    additionally, we see 4-5 countries on the list… and I think the attackers are stubborn people, so the list might become longer after these settings.

  • @phenomlab they have firewall but we have to input individual rules, there is no country block.

    Additionally, we use UFW and we only allow https.

    wrote on last edited by
    #8

    @crazycells In addition, if you are using Virtualmin, you can leverage Fail2Ban which is a lot more powerful.

  • @crazycells In addition, if you are using Virtualmin, you can leverage Fail2Ban which is a lot more powerful.

    wrote on last edited by
    #9

    @phenomlab yes, we do have fail2ban set up already, sorry I wrote in the first post, but I did not write the usual way 😄 Fail2Ban

  • @phenomlab yes, we do have fail2ban set up already, sorry I wrote in the first post, but I did not write the usual way 😄 Fail2Ban

    wrote on last edited by phenomlab
    #10

    @crazycells There is also a way to do this with fail2ban using

    https://blog.reinhard.codes/2023/04/02/restricting-access-to-ssh-using-fail2ban-and-geoip/

    Obviously, you substitute port 22 (SSH) for port 443 (HTTPS)

  • @crazycells There is also a way to do this with fail2ban using

    https://blog.reinhard.codes/2023/04/02/restricting-access-to-ssh-using-fail2ban-and-geoip/

    Obviously, you substitute port 22 (SSH) for port 443 (HTTPS)

    wrote on last edited by
    #11

    @phenomlab can I ask your values of these settings?

    Screen%20Shot%202023-11-15%20at%2018.38.00.jpeg

  • @phenomlab can I ask your values of these settings?

    Screen%20Shot%202023-11-15%20at%2018.38.00.jpeg

    wrote on last edited by
    #12

    @crazycells I’d leave those as they are and handle this much further upstream (at NGINX or OS level)

  • @crazycells I’d leave those as they are and handle this much further upstream (at NGINX or OS level)

    wrote on last edited by
    #13

    @phenomlab we already have those settings changed before, so it might help if I know the default values… 😊 I guess you have them unchanged? Can I learn those default values?

  • @phenomlab we already have those settings changed before, so it might help if I know the default values… 😊 I guess you have them unchanged? Can I learn those default values?

    wrote on last edited by
    #14

    @crazycells Of course - see below

    81935872-9237-4794-8f01-b5c0a32c7c3b-image.png

  • wrote on last edited by
    #15

    maybe we should switch to aws, it has a shield for ddos protection…

    https://aws.amazon.com/shield/ddos-attack-protection/

    which provider do you think is best against ddos attacks?

  • maybe we should switch to aws, it has a shield for ddos protection…

    https://aws.amazon.com/shield/ddos-attack-protection/

    which provider do you think is best against ddos attacks?

    wrote on last edited by phenomlab
    #16

    @crazycells Hetzner also has excellent DDoS protection, a stateful firewall, and I have a referral link meaning you get credits for free… 🙂

    EDIT: Much of this really depends on where you want your server placed. Hetzner are based in Germany, Helsinki, and now the US 🙂

    https://www.hetzner.com/cloud

  • @crazycells Hetzner also has excellent DDoS protection, a stateful firewall, and I have a referral link meaning you get credits for free… 🙂

    EDIT: Much of this really depends on where you want your server placed. Hetzner are based in Germany, Helsinki, and now the US 🙂

    https://www.hetzner.com/cloud

    wrote on last edited by
    #17

    @phenomlab sure, please send me your link. we were considering aws quite some time, but I will send your link to our developer as well, so he can make decision.

    in general, we were trying to stay away from europe or european products due to strict laws and requirements. our user base is either from the US or from Turkey, so we prefer to decrease the amount of work we do 😄

  • @crazycells Hetzner also has excellent DDoS protection, a stateful firewall, and I have a referral link meaning you get credits for free… 🙂

    EDIT: Much of this really depends on where you want your server placed. Hetzner are based in Germany, Helsinki, and now the US 🙂

    https://www.hetzner.com/cloud

    wrote on last edited by
    #18

    @phenomlab oh I see a link there now, but I believe that is not referral link?

  • @phenomlab sure, please send me your link. we were considering aws quite some time, but I will send your link to our developer as well, so he can make decision.

    in general, we were trying to stay away from europe or european products due to strict laws and requirements. our user base is either from the US or from Turkey, so we prefer to decrease the amount of work we do 😄

    wrote on last edited by phenomlab
    #19

    @crazycells You’d be better placed with Hetzner in the US I think. AWS can get VERY expensive very quickly. My referral link for Hetzner is below.

    I personally use Hetzner and also have a “storage box” with 1Tb of storage for backups located in another datacentre for recovery purposes.

    https://hetzner.cloud/?ref=b2bBQLHF3mEV

  • wrote on last edited by
    #20

    This might also be useful…

    image.png

  • This might also be useful…

    image.png

    wrote on last edited by
    #21

    @phenomlab on a side note, is there any easy way to implement a rule… to allow only two geolocation (countries) but block the access from the rest of the countries?

  • @phenomlab on a side note, is there any easy way to implement a rule… to allow only two geolocation (countries) but block the access from the rest of the countries?

    wrote on last edited by
    #22

    @crazycells yes, but without Cloudflare you’d need to perform more checks to determine traffic origin before you have make a decision as to block or permit.

  • @crazycells yes, but without Cloudflare you’d need to perform more checks to determine traffic origin before you have make a decision as to block or permit.

    wrote on last edited by
    #23

    @phenomlab yes, we are planning to install Cloudflare again…

    We will go with “Pro” version and see how it works, I guess this should help not to have any session errors… Previously, we got many connection problems because of Cloudflare…

  • @phenomlab yes, we are planning to install Cloudflare again…

    We will go with “Pro” version and see how it works, I guess this should help not to have any session errors… Previously, we got many connection problems because of Cloudflare…

    wrote on last edited by
    #24

    @crazycells I wouldn’t be so sure. The pro version of Cloudflare is $20 per month but I don’t think that will resolve the connectivity issues.

    There also the harm that CF causes to SEO if you use their bot fight mode as I mention here

    https://sudonix.org/topic/503/cloudflare-bot-fight-mode-and-google-search

  • @crazycells I wouldn’t be so sure. The pro version of Cloudflare is $20 per month but I don’t think that will resolve the connectivity issues.

    There also the harm that CF causes to SEO if you use their bot fight mode as I mention here

    https://sudonix.org/topic/503/cloudflare-bot-fight-mode-and-google-search

    wrote on last edited by
    #25

    @phenomlab I have a good news. We set up CloudFlare Pro, and did not have connection problems yet.

    As you said, it costs $20/month if you subscribe annually, but we did monthly ($25) since we were not sure if this will work for us. So far everything looks OK. We will also check “Google Search” problem you mentioned as well after we secure our forum. Thanks a lot for this warning!

    Unfortunately, we had no choice about Cloudflare since we were getting more than 1 billion connection request from bots and forum was unusable for several hours two consecutive days…

    Screen Shot 2023-11-15 at 16.49.45.png

    Screen Shot 2023-11-18 at 13.22.28.png

    Screen Shot 2023-11-18 at 13.24.55.png

  • @phenomlab I have a good news. We set up CloudFlare Pro, and did not have connection problems yet.

    As you said, it costs $20/month if you subscribe annually, but we did monthly ($25) since we were not sure if this will work for us. So far everything looks OK. We will also check “Google Search” problem you mentioned as well after we secure our forum. Thanks a lot for this warning!

    Unfortunately, we had no choice about Cloudflare since we were getting more than 1 billion connection request from bots and forum was unusable for several hours two consecutive days…

    Screen Shot 2023-11-15 at 16.49.45.png

    Screen Shot 2023-11-18 at 13.22.28.png

    Screen Shot 2023-11-18 at 13.24.55.png

    wrote on last edited by
    #26

    @crazycells well, of course 1 billion+ requests happened after we installed CF, I do not know how many more we had before installing CF…


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