Hey all,

I configured a few Firefox browser to surf through our web proxy.
However, when connecting google.com, I have a message from Google explaining that my request is suspicious:
How Google detects my proxy ?
Can I do something in my config to keep using Google and my proxy ?

Thanks

Are you saying that if you stop using the proxy, you aren't blocked?

I ask because this doesn't sound proxy-related to me. Instead, it sounds like Google has determined that your public IP is engaging in suspicious behavior and has temporarily banned you. I do remember this happened to me once, but I can't remember what caused it (the ban was lifted after a few hours IIRC).

Is your public IP static or dynamic? If it's dynamic, perhaps the previous lease holder is responsible for ticking off Google? How long have you had your current public IP? Are you positive there really aren't any infected Windows boxes on your LAN?

Right.

However, I have to precise that when I don't use the proxy, the client are connecting with another IP address (we have 2 public static IP address).

So, it would not be related to the configuration of firefox or the proxy ? But it would be a blacklisting of the other IP(where the proxy is located) from Google ?

That's what it sounds like to me. Verifying that should be relatively easy, though. Basically you'd just need try both IPs with/without the proxy. If you determine it's solely an IP-based ban, then you should probably inspect your LAN to make sure nothing out of the ordinary is happening. If everything checks out, you might not have an option aside of waiting for the ban to expire. Does it happen regardless of which IP you use for the Google address? If not, then you could force the LAN to use a certain IP for google.com while this is fixed. Although if Google has this kind of thing centralized then it wouldn't matter which of their servers you use (they will all block you). But you'd need to give it a shot to see.

Delete your browser cache and Google cookies. Even on linux and without a proxy I have had that same message a few times. Google can be retarded at times.

It wouldn't hurt to try that, of course.

But if cookies are the problem, why won't it happen when the other public IP is used?

Damn !
I am not in charge of the other IP adress (it is a contract with another ISP).
Firewalling rules can't be change, therefore squid is the only way to do HTTP on this public IP address.

I am still wondering if it is coming from Firefox proxy configuration or from the IP itself.

For my knowledge, can a remote server "see" that it is not a web browser that connects but a proxy ?