Hello,

I setup a squid as transparent proxy on CentOS7. I setup squid with IPtables with NAT and now if want to setup internet by setting up a proxy setting on browser from client internet is not working and i am getting "TAG_NONE/409 4347 CONNECT www.google.com:443 - HIER_NONE/- text/html" error in /var/log/squid/access.log.

But without proxy setting in browser internet is working fine. While googling in found to setup dns_v4_first on in squid.conf but still the same issue.

Can you please help me to figure out this issue.

I also verified that port 3128 is open on gateway.

Read this for an explanation and try the suggestions in the reply.

Regards

@bathory :- Thanks for the reply
I went through the link but mine issue is that when i add the gateway proxy settings in browser, internet stop working for http:// as well as https:// and both have a different errors [Attached are the screenshot]. I open http://yahoo.com then it says "Access Denied" while on accessing https:// it says ERR_TUNNEL_CONNECTION_FAILED.

Below are the errors found in access.log
On Accessing https://
Local_IP TAG_NONE/409 4347 CONNECT www.google.com:443 - HIER_NONE/- text/html

On Accessing http://
171.113.249.113 TCP_DENIED/403 4219 GET http://m.search.yahoo.com/ - HIER_NONE/- text/html

However when i remove the proxy setting from browser (As squid is setup as transparent proxy as well with IPtables) then all is working fine.

And i am not using SSL_bump for my squid proxy for now.

Attached Thumbnails

     

For this you need to look again at my previous post


The above means that there is an ACL in squid configuration file that forbids access to your client.
Without the relevant squid config directives, we cannot tell what exactly is the problem


If you're going to setup squid as a transparent proxy, there is no need to mess with the browser settings. Outgoing traffic to port 80 is passing through the squid proxy by the iptables rules.

Thanks @bathory

[PHP]Without the relevant squid config directives, we cannot tell what exactly is the problem

acl our_network src 192.16.17.0/24 10.0.0.0/8 192.168.15.0/24
acl localnet src 10.0.0.0/8 # RFC1918 possible internal network
acl localnet src 172.16.0.0/12 # RFC1918 possible internal network
acl localnet src 192.168.0.0/16 # RFC1918 possible internal network
acl localnet src fc00::/7 # RFC 4193 local private network range
acl localnet src fe80::/10 # RFC 4291 link-local (directly plugged) machines

acl SSL_ports port 443
acl Safe_ports port 80 # http
acl Safe_ports port 21 # ftp
acl Safe_ports port 443 # https
acl Safe_ports port 70 # gopher
acl Safe_ports port 210 # wais
acl Safe_ports port 1025-65535 # unregistered ports
acl Safe_ports port 280 # http-mgmt
acl Safe_ports port 488 # gss-http
acl Safe_ports port 591 # filemaker
acl Safe_ports port 777 # multiling http
acl CONNECT method CONNECT

#CONNECT use ipv4 resolution first
dns_v4_first on

#
# Recommended minimum Access Permission configuration:
#
# Deny requests to certain unsafe ports
http_access deny !Safe_ports

# Deny CONNECT to other than secure SSL ports
http_access deny CONNECT !SSL_ports

# Only allow cachemgr access from localhost
http_access allow localhost manager
http_access deny manager
# We strongly recommend the following be uncommented to protect innocent
# web applications running on the proxy server who think the only
# one who can access services on "localhost" is a local user
#http_access deny to_localhost

#
# INSERT YOUR OWN RULE(S) HERE TO ALLOW ACCESS FROM YOUR CLIENTS
#

# Example rule allowing access from your local networks.
# Adapt localnet in the ACL section to list your (internal) IP networks
# from where browsing should be allowed
http_access allow localnet
http_access allow localhost
http_access allow our_network

# And finally deny all other access to this proxy
http_access deny all

# Squid normally listens to port 3128
http_port 3128 intercept

# Uncomment and adjust the following to add a disk cache directory.
cache_dir ufs /var/spool/squid 1000 16 256

#Define Cache Memory
cache_mem 1048 MB

# Leave coredumps in the first cache dir
coredump_dir /var/spool/squid

#
# Add any of your own refresh_pattern entries above these.
#
refresh_pattern ^ftp: 1440 20% 10080
refresh_pattern ^gopher: 1440 0% 1440
refresh_pattern -i (/cgi-bin/|\?) 0 0% 0
refresh_pattern . 0 20% 4320

Reason being use this proxy setting through browser as some of client machine using tunnel (Cisco) to communicate with remote machines and internet is not setup on this tunnel. Now browser's proxy settings need to use to get internet working on these machines.
However we were using squid 2.6 before and this was working fine with same configuration and scenario.

So indeed there is no 171.113.249.113 among the IPs/networks that are allowed to use squid proxy.


I don't know what was changed, but I suggest you to re-read this and see if it helps.

This is not our network IP, i don't know how it log into access.log

I will go through this link and see if it works.

Hello bathory,

I configured and tested the transparent proxy by modify the squid.conf and by adding below 2 lines i got this issue fixed. Rest of the SSL bump related configured get commented by me.

Now when we are accessing internet using browser proxy settings it is accessible and working.

Thanks.

Hi sunnysthakur,

Thanks for posting the solution.
You may mark the thread "SOLVED" from the "Thread Tools" on top of the page.

Cheers

You saved my day...
Spent 4 hours on this issue..
Thanks, guys!