On Fri, Feb 26, 2016 at 3:01 PM, Philip Lavine via NANOG <nanog@nanog.org> wrote:
Does anybody know what the threshold for google searches is before you get the captcha?I am trying to decide if I need to break up the overload NAT to a pool.
There isn't a threshold -- if you send automated searches from an IP, then it gets blocked (for a while). So... this comes down to how much you trust your machines/users. If you're a company with managed systems, then you can have thousands of users share the same IP without problems. But if you're an ISP, you'll likely run into problems much earlier (since users like their malware). Some tips: - if you do NAT: try to partition users into pools so one abusive user can't get all your external IPs blocked - if you have a proxy: make sure it inserts the X-Forwarded-For header, and is restricted to your own users - if you're an ISP: IPv6 will allow each user to have their own /64, which avoids shared-fate from abusive ones Damian (responsible for DDoS defense) -- Damian Menscher :: Security Reliability Engineer :: Google :: AS15169