Hello,
We are migrating our gateways from CentOS 6 to CentOS 7 and for setting up a transparent proxy using squid and Firewalld i am using below configuration.
#Firewalld configurations
firewall-cmd --permanent --zone=public --add-forward-port=port=80:proto=tcp:toport=3128:toaddr=LAN_IP
firewall-cmd --permanent --zone=public --add-port=3128/tcp
firewall-cmd --permanent --add-masquerade
firewall-cmd --reloa
#Allowed ports
#firewall-cmd --zone=public --add-port=3128/tcp --permanent
#firewall-cmd --zone=public --add-port=8080/tcp --permanent
#firewall-cmd --zone=public --add-port=443/tcp --permanent
#firewall-cmd --zone=public --add-port=80/tcp --permanent
#firewall-cmd --zone=public --add-port=22/tcp --permanent
#Allow LAN Network in squid.conf [Version 3.5.20]
acl our_network src 192.168.2.0/24 10.0.0.0/8 192.168.15.0/24
# Allow Network ACL Allow/Deny Section#
http_access allow our_network
# Transparent Proxy Parameters
http_port 3128 intercept
Now the issue is that we are able to access internet using this gateway on mentioned series but not able to access the services like mstsc/ssh to other machine, not able to access internal web page/URL setup on internal IP. however we are able to ping the IPs.
however we tried disable Firewalld and use iptables instead on CentOS 7 but this setup even not working (even internet not working)
Previously gateway was setup on CentOS 6 and was working fine with below configuration and there wasn't any issue like we fare facing as above.
#Allow LAN Network in squid.conf [Version 3.1.23]
acl our_network src 192.168.2.0/24 10.0.0.0/8 192.168.15.0/24
# Allow Network ACL Allow/Deny Section#
http_access allow our_network
# Transparent Proxy Parameters
http_port 3128 transparent
#Below is the bash script we use to setup squid/iptables as transparent proxy. We call this script using /etc/rc.local
#!/bin/sh
#squid server IP
SQUID_SERVER="WANIP"
# Interface connected to Internet
INTERNET="eth0"
# Interface connected to LAN
LAN_IN="eth1"
# Squid port
SQUID_PORT="3128"
# DO NOT MODIFY BELOW
# Clean old firewall
iptables -F
iptables -X
iptables -t nat -F
iptables -t nat -X
iptables -t mangle -F
iptables -t mangle -X
# Load IPTABLES modules for NAT and IP conntrack support
modprobe ip_conntrack
modprobe ip_conntrack_ftp
# For win xp ftp client
#modprobe ip_nat_ftp
echo 1 > /proc/sys/net/ipv4/ip_forward
# Setting default filter policy
iptables -A FORWARD -p tcp --dport 135:139 -o eth0 -j DROP
iptables -A OUTPUT -p tcp --dport 135:139 -o eth0 -j DROP
iptables -A OUTPUT -p udp --dport 135:139 -o eth0 -j DROP
iptables -A FORWARD -p udp --dport 135:139 -o eth0 -j DROP
iptables -A FORWARD -p tcp --dport 445 -o eth0 -j DROP
iptables -A FORWARD -p udp --dport 445 -o eth0 -j DROP
iptables -A OUTPUT -p tcp --dport 445 -o eth0 -j DROP
iptables -A OUTPUT -p udp --dport 445 -o eth0 -j DROP
iptables -P INPUT ACCEPT
iptables -P OUTPUT ACCEPT
# Unlimited access to loop back
iptables -A INPUT -i lo -j ACCEPT
iptables -A OUTPUT -o lo -j ACCEPT
# Allow UDP, DNS and Passive FTP
iptables -A INPUT -i $INTERNET -m state --state ESTABLISHED,RELATED -j ACCEPT
# set this system as a router for Rest of LAN
iptables --table nat --append POSTROUTING --out-interface $INTERNET -j MASQUERADE
iptables --append FORWARD --in-interface $LAN_IN -j ACCEPT
# unlimited access to LAN
iptables -A INPUT -i $LAN_IN -j ACCEPT
iptables -A OUTPUT -o $LAN_IN -j ACCEPT
# DNAT port 80 request comming from LAN systems to squid 3128 ($SQUID_PORT) aka transparent proxy
iptables -t nat -A PREROUTING -i $LAN_IN -p tcp --dport 80 -j DNAT --to $SQUID_SERVER:$SQUID_PORT
#iptables -t nat -A PREROUTING -i $LAN_IN -p tcp --dport 443 -j DNAT --to $SQUID_SERVER:$SQUID_PORT
# if it is same system
iptables -t nat -A PREROUTING -i $INTERNET -p tcp --dport 80 -j REDIRECT --to-port $SQUID_PORT
#iptables -t nat -A PREROUTING -i $INTERNET -p tcp --dport 443 -j REDIRECT --to-port $SQUID_PORT
# DROP everything and Log it
iptables -A INPUT -j LOG
iptables -A INPUT -j ACCEPT
Can you help me out to fix this issue. Am i missing some firewalld rules due to which services are not accessible or what else i am missing.
