cancel
Showing results for 
Search instead for 
Did you mean: 
ittech
Level 13

Proxy received an invalid response

Jump to solution

We are a local govt. agency and must connect to other agencies (like the county) for certain services. After testing the MWG7 in our PD they cannot get through and the gateway gives a Proxy received an invalid response screen.

ProxyProblem.png

In the bottom lefthand of the screen you can see that the rule is being applied, but the site is being stopped for some reason.

Here is my rule to allow the site:

ProxyProblem2.png

If it helps, before I pute the Trusted Sites rule into place, this page was being blocked by the "Block is Virus was Found" rule.

Any help is greatly appreciated and the ASAPier the better

THANKS!

0 Kudos
1 Solution

Accepted Solutions
salanis
Level 10

Re: Proxy received an invalid response

Jump to solution

ittech-

Please take a look at the screen shot.

The Web Gateway can't reach the site. It appears to be blocked by a firewall.

0 Kudos
9 Replies
asabban
Level 17

Re: Proxy received an invalid response

Jump to solution

This looks like there is something strange communicated back by the destination Website. I think a tcpdump will most likely reveal what is happening. Are you able to create one for us to check?

Best,

Andre

0 Kudos
ittech
Level 13

Re: Proxy received an invalid response

Jump to solution

Can you point me to a goop app for that, please?

0 Kudos
asabban
Level 17

Re: Proxy received an invalid response

Jump to solution

Hey,

please go to the Troubleshooting section on the GUI. You can create a Packet Capture there.

There is a command line on the top which should take "-s 0" as a parameter. Then click "start", replicate the issue, click "stop" and send in the result.

Best,

Andre

0 Kudos
ittech
Level 13

Re: Proxy received an invalid response

Jump to solution

Here is the tcpdump.

Thanks for help eveyone!

0 Kudos
salanis
Level 10

Re: Proxy received an invalid response

Jump to solution

ittech-

Please take a look at the screen shot.

The Web Gateway can't reach the site. It appears to be blocked by a firewall.

0 Kudos
ittech
Level 13

Re: Proxy received an invalid response

Jump to solution

Okay, so unbeknownst to me the county's side only accepted IP within a certain range from our city. So, I quickly added another IP to the Gateway and changed the Gateway's gateway (ha!) and everything is fine now

Thanks for all your help, more questions coming soon!

...like seriously, 5 minutes soon.

0 Kudos
salanis
Level 10

Re: Proxy received an invalid response

Jump to solution

iitech-

Thank you for your question.

The best method to find the cause is to get a network capture going out to the site in question without the proxy.

Then point to the proxy and replicate whilst running a new network capture and compare the two.

Wireshark is such a indispensible tool I wouldn't know what to do without it (wireshark.org)

If I suspect being the host sending invalid HTTP responses I disable all my rule sets and replicate going through the proxy. At the same time, since this is a "trusted" site you should have a white list above all your rule sets which will stop the cycle and thus bypass all filtering if you belive this to be cause.

on 11/19/10 8:42:58 AM CST
0 Kudos
ittech
Level 13

Re: Proxy received an invalid response

Jump to solution

Can anyone help me with the CLI commnd to change the network address of interface 0?

0 Kudos
salanis
Level 10

Re: Proxy received an invalid response

Jump to solution

why do you want to change the address of the interface?

This has to be done via the gui for this to be permanent.

However,  to change it via the command line run:

ifconfig eth0 192.168.0.1 netmask 255.255.255.0

This is just an example.

0 Kudos