Tag: TCP_MISS/503

HowTo: Allow Browsing in Squid for URLs with port numbers (i.e.: http://ugc-hemis.gov.bd:81/) in the Proxy Server


A system Administrator wants to allow URLS with Port Number. But adding the port number in the Firewall and Squid will not solve the problem of allowing the URLs with port number. The SQUID shows the TCP_MISS/503 in SQUID Log (/var/log/squid/access.log) file. This means the Permission is denied for the request made by the Client.


Step 1:

Open the

/etc/squid/squid.conf      file    and

add the line (if your URL contains port as 81)

acl Safe_ports port 81

Step 2:

Restart the Squid service by

service squid restart

Step 3:

Add the port number in the Firewall

iptables -A INPUT -p tcp –dport 81 -j ACCEPT

Step 4:

Edit the SELINUX File by opening

/etc/sysconfig/selinux file

and Edit the file as


Step 5:

Restart the Machine by:

reboot command

And you are done with this. You can browse to any port number by allowing in your squid file now.

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