topic Re: PC behind ASA suddenly not able to browse to website in Network Security

PC behind ASA suddenly not able to browse to website

Mohd Khairul Nizam — Tue, 23 Jun 2020 06:59:42 GMT

Hi,
Last 2 day, network cable between ASA and SW faulty, thus we have changed it.
but after that , weird think is email not able to send/receive and unable to open google.com, gmail.com

the user using smtp.gmail.com & pop.gmail.com

other URL website able to open.

weird ??

anyone can help

attached is the config

Re: PC behind ASA suddenly not able to browse to website

Dennis Mink — Thu, 19 Jul 2018 02:10:27 GMT

can you ping fw, and 8.8.8.8?

Re: PC behind ASA suddenly not able to browse to website

Mohd Khairul Nizam — Thu, 19 Jul 2018 02:30:13 GMT

from the PC, unable to ping 8.8.8.8

but from the ASA console able to ping 8.8.8.8 & 8.8.4.4

Re: PC behind ASA suddenly not able to browse to website

Dennis Mink — Thu, 19 Jul 2018 05:07:45 GMT

can you ping the internal ip address of the asa from PC?

Re: PC behind ASA suddenly not able to browse to website

Mohd Khairul Nizam — Thu, 19 Jul 2018 05:17:35 GMT

yes, we can
pls note that, PC able to access all website except google & gmail
which is not logic at all...

Re: PC behind ASA suddenly not able to browse to website

aaron.hackney — Tue, 24 Jul 2018 15:01:25 GMT

If you can access everything except google products, then there could be a few things going on, few of which are firewall related.

1. The hosts file could be corrupt on the host. Does DNS resolve for these sites?

2. Your NATed IP could be blacklisted by Google

3. Your firewall could have a shun for some critical google IP.

show shun

4. There is a corrupt session in the browser. Try a private window.

Personally, I would t-shoot this with a packet capture on the firewall and examine the results in Wireshark.

Re: PC behind ASA suddenly not able to browse to website

Mohd Khairul Nizam — Wed, 08 Aug 2018 01:07:42 GMT

just to update

the issues is resolved.

the resolution is have to manually use Google DNS in order the traffic to go through.
Just a little bit weird,