For security reasons and to save bandwidth I would like to configure Squid proxy server such way that my users should not download all of the following files:

How do I configure squid content filtering?

You need to use squid ACL (access control list) to block all files by extensions.

How do I block music files using squid content filtering ACL?

First open your squid.conf file /etc/squid/squid.conf, run:
# vi /etc/squid/squid.conf
Now add the following lines to your squid ACL section:

acl blockfiles urlpath_regex -i "/etc/squid/blocks.files.acl"
You want display custom error message when a file is blocked:
# Deny all blocked extension
error_directory /usr/share/squid/errors/English
deny_info ERR_BLOCKED_FILES blockfiles
http_access deny blockfiles

Save and close the file.Create a custom error message HTML file called ERR_BLOCKED_FILES in /etc/squid/error/ directory or /usr/share/squid/errors/English directory:
# vi /usr/share/squid/errors/English/ERR_BLOCKED_FILES
Append following content:

<TITLE>ERROR: Blocked file content</TITLE>
<H1>File is blocked due to new IT policy</H1>
<p>Please contact helpdesk for more information:</p>
 <li>Phone: 555-12435 (ext 44)</li>

Now create a new file named /etc/squid/blocks.files.acl file:
# vi /etc/squid/blocks.files.acl
Append following text:

Save and close the file. Restart Squid:
# /etc/init.d/squid restart
Squid in action:

Fig.01: Squid in action

Fig.01: Squid in action

Say hello to rep_mime_type

To block Active Stream Format (Windows Media Player) and flash video format, add the following in your squid.conf:

acl media rep_mime_type x-ms-asf
acl mediapr urlpath_regex \.(afx|asf)(\?.*)?$

acl media rep_mime_type video/flv video/x-flv
acl mediapr urlpath_regex \.flv(\?.*)?$

http_access deny mediapr
http_reply_access deny media

Save and close the file. Reload squid server:
# systemctl reload squid
# squid -k reconfigure

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83 comments… add one
  • AJ Jan 9, 2007 @ 13:01

    I use squid but all my filterings is done via dansguardian. Bannerfilter is great to stop adverts. And web custome written based admin console keeps my non un*x admins happy

  • Bhavik Mar 7, 2007 @ 15:18

    In Squid, i want to do the routing through users?
    eg. user-a, user-b if user a can access internet then data transer through 246kbps line & if user-b access internet then it’s data transer through 1mbps line.
    [note:- user-a & user-b can set any where, any pc in network]

  • Nandkishor Apr 3, 2007 @ 10:24

    I do the following configuration in squid but it is not possible to block the downloads.
    Plz give me the solution for this

  • Kubitsch Apr 11, 2007 @ 14:50

    Hello, thanks, but it dosnt work for me…no effect.


  • Zahid Iqbal Apr 12, 2007 @ 10:28

    In squid how I can block files for a particular IP or user

    • John_Umesh Dec 22, 2010 @ 9:20

      First u create acl where u’ll mention IP address to block,
      Then add rule to deny that acl.

      This may help u


  • Omer Jun 18, 2007 @ 10:43

    it worked for me , but it seems that still users are able to download files dont know how.
    how i can totally block the download from users.
    if u have downloading agent, then it by-pass and start download.
    How can i make it strong so that no one can download any thing through any software.

  • saravanaprakash Aug 2, 2007 @ 11:13

    Hi ,
    i was config my proxy successfully. But i can’t access my outlook. i think its prots are blocked.
    Then how can i unlock my outlook ports…
    If anybody konw the solution, Please Immediately send to me… my NAT server ip was given to the gateway of my proxy server and proxy server gateway was given to the users gateway.. Its correct or not ..
    If u know any other way….. please share with me…

    I want the correct solution immediately…

    MY personal EMAIL ID is

  • dasappan Aug 8, 2007 @ 9:44

    my office is blocked to down load mp3 files. Can you please help me how to down load mp3 files.

    Your favourable reply will be highly appreciated.

    Thanks in advance


  • amin Aug 10, 2007 @ 3:53

    Dear Sir,

    I have followed your step-by-step instruction to block download files.

    i succesfully manage to block the files while clicking selected files. and i received error msg from squid.

    Unfortunately i still manage to download that file by simply using “Save Link As..” menu as i right click the mouse.

    it seem like users still manage to download prohibited file as configured in squid by using right click menu.

    please advice.



  • Nov 11, 2007 @ 11:25


    What if i want to…
    replace “Men at work” with “Aliens at party”

    Is this possible ?
    Can i do this in squid without using any addons ?

  • chzia Nov 14, 2007 @ 10:24

    This did not work at all. It is not blocking downloads. Yes one thing was possible that downloading by right clik and save target was stoped, rest all downloads are working. Not a good solution. Pls advise for another.

  • becci Nov 16, 2007 @ 9:34

    is there away to unblock bebo cuz are school is gay and has filtered ALL the proxy sites to date
    thanks becci

  • sankar Dec 14, 2007 @ 3:56

    please help me

    restric the download option in proxy linux server

  • regex_warrior Feb 29, 2008 @ 18:57

    That won’t stop me from doing


  • shankar Mar 4, 2008 @ 14:15

    Hai friends pls help me in this

    I our Company we have 200 system and one linux server i want to configure squid in a way that no body should download files in my network and 2 to 3 system i should give premision to download can any body help me plzzzzzzzzzz.

  • Cru3L Apr 29, 2008 @ 0:57

    Is it possible to block downloads from yahoo mail and other web based email in Squid? I can block downloads using the instructions above but it can only block direct download from a site.

  • ammaro May 13, 2008 @ 11:55

    our admin blocked all media files if anybody can help me break his policy,,,

  • Rico May 13, 2008 @ 18:12

    The blocking file list can be simpler by adding “-i” to the blockfiles statement in squid.conf, that is:
    acl blockfiles urlpath_regex -i “/etc/squid/blocks.files.acl”

    # and in
    # /etc/squid/blocks.files.acl

  • Rico May 13, 2008 @ 18:29

    shankar, you can do it like this:
    in your squid.conf

    acl special_grp src “/etc/squid/special_grp”
    acl blocked_files url_regex -i “/etc/squid/blocked_files

    http_access allow special_grp blocked_files
    http_access deny !special_grp blocked_files

    # make sure the above lines are above the line “http_access allow our_networks”

    in your /etc/squid/special_grp enter the ips of the systems (one ip per line) that you allow to download and in your /etc/squid/block_files enter the following content

    Then reload squid and you are all set.

  • ASP Consultant Jun 23, 2008 @ 8:02

    it’s done by easy step like
    acl downloadfiles urlpath_regex -i “/etc/squid/downloadfiles.acl”

    http_access deny downloadfiles

  • Rashid Shafique Aug 8, 2008 @ 16:14

    i want me to download mp3 of my choice but it is just saves the file as HTML document rather than mp3 format how i can get rid of it.i use the intrnet provided by LAN of my company.

  • Amani Makota Aug 27, 2008 @ 8:31

    This is my first time to enter in to this forum.

    I want to block users to more than 5MB per day.How can I do so.
    I am using Lunix Fedora


  • venkat Jan 31, 2009 @ 11:05

    Hi everone,I had configure squid proxy server still it’s working but i need restrict to downloads for users can u help.already i am doing like.acl blickfile urlpath _ regix -i “/etc/squid/blocks.filies.acl”
    http_access deny blockfiles
    deny_info ERR_BLOCKED_FILES blockfiles acl
    iam creating file block.files.acl under squid
    mention all extention on that file like \.exe$
    after restarting the sevice
    but .exe file will downloaded . Can you help where exact problem found.


  • Rico Feb 17, 2009 @ 2:01

    The method described in this post can be easily passed if user appends a single question mark or to supply some information that is not required, see it yourself:

  • varun Mar 12, 2009 @ 20:07

    Hello, I have hostel Boys downloard movies I dont want. how can i block all downloarding. we are providing wi-fi. if i block my server is that ok for all ??? please reply very urgent at

  • Khalil Mir Apr 17, 2009 @ 4:21

    Dear All,
    I have done above procedure & it is working good, but there is a problem,
    It also blocked symantec live update, Kindly help me for allow symantec live update with these reistrictions.

  • kamal sen Apr 22, 2009 @ 12:07

    sir I want to configure the squid proxy server file in such a way that it contains one public IP and two private IP (EX ) and and block various sites (I.E , blocl exe file download etc) but in some ip there is no rule ; please tell me how can i configure that proxy server .

  • V.Balaviswanathan May 4, 2009 @ 13:17

    Please help me configure

    Sir,in my company we have two gateways and need to give access only to few selected people in my office. and they need to configure through squid. Please help me… Can anyone help me. If so i would be thankful to them


  • ishtiaq May 29, 2009 @ 12:10

    Is this possibe that if a network/IP not allowed in squid try to come through his/her browser ( by using the squid IP in the browser) then his/her browser should display a message ( you are not allowed to come throught this proxy or any other message)

    Waiting .

    Ishtiaq Ahmed

  • Sheikh Amjad Zia Jun 16, 2009 @ 14:13

    i am usind squid in linux for proxy server i want to block the downloading , music file of all types of extensions image file for user side please guide mein this regard. & also i want to block chatting all kinds of messangers.

  • SHEIKH AMJAD ZIA Jun 18, 2009 @ 7:27

    how are you i am facing a problem regarding blocking of unwanted sites in my network using squid please help me in this regards. i want to block all kinds of messangers, chat sites musical sites & all other voulger sites. i am waiting for your quick response.


    Amjad Shaikh

  • V.Balaviswanathan Jun 18, 2009 @ 8:20

    @ Amjad

    Hi , you need to create the acl for that I wll give you the syntax for that

    under acl tag write like this
    acl block url_regex “/etc/squid/squid-block.acl”
    and under http_access block
    http_access allow manager should be changed to http_access allow all
    http_access deny block
    and create a seperate file squid-block.acl and list out those unwanted sites and then reload the squid.
    Make sure that ur internet connection is made through proxy

    Regarding messanger and chat sites you need to use iptables

  • ajeet Jul 1, 2009 @ 8:30

    how to block porn website using squid server

  • ajeet Jul 1, 2009 @ 8:33

    how to block websites

  • kiranjith Sep 1, 2009 @ 9:33

    could some one please guide me that how to integrate the squid with Active directory to filter/ schedule the access to web based on the usernames (From Active directory)

  • Kamran Rashid Khan Oct 28, 2009 @ 5:58

    How can i blcok Gpass,Freegate & UltraSurf using Fedora 11 Squid Proxy.

  • rajen Nov 13, 2009 @ 12:43

    we have got wi-fi by college but we are unable to download any videoes or we can’t even see suggest us..

  • Usman Arif Dec 30, 2009 @ 10:38

    hi how r u .would u like to tell where we place this lines please
    can u send code with example

    http_access allow special_grp blocked_files
    http_access deny !special_grp blocked_files

  • Usman Arif Dec 30, 2009 @ 10:40

    i block downloading on fedora i want to allow some ip to download and watch online movie
    how can i make white class of these ip

    plz inform with example

  • kushal rajpurohit Dec 31, 2009 @ 9:50

    Dear Sir,

    I have followed your step-by-step instruction to block download files.

    i succesfully manage to block the files while clicking selected files. and i received error msg from squid.

    Unfortunately i still manage to download that file by simply using “Save Link As..” menu as i right click the mouse.

    it seem like users still manage to download prohibited file as configured in squid by using right click menu.

    please advice.


  • rocaboy1uk Jan 27, 2010 @ 11:15


    Is this the route one would take to create a music download service? By that I mean, if a user has not paid for certain music, they can be restricted from downloading a particular track or album, however if they have paid they are granted access. Also, if it is a shared environment with access only to a DB such as MySQL and a scripting language such as PHP, how would this be possible?

  • Sheikh Amjad Zia Jan 29, 2010 @ 6:53

    How are you, i hope that you are fine , on my MINUX Machine an error messgae is dispalyed when i start the machine please solve my problem on urgent bases the error message is as “Maximum Memory Performance is achieved with matched DIMMS. The Installed amountof memory in Channel A is not equal to the amount of press any key to continue”

    i am waiting for your quick & positive reply.

    Amjad Zia

  • Omer ijaz Feb 1, 2010 @ 22:34

    I want to allow all sites accpect my live video streaming websits i.e youtube ,matacafe
    how i can able to do that plz spourt me


  • khalil Feb 4, 2010 @ 13:19

    Dear Mr. Atul,
    Can u help me , I want to access my apps server from internet (out side of my local area network). your help is highly thanfull.

    khalil mir

  • Manish Chaudhary Feb 6, 2010 @ 8:11

    hiiiiiiiii sir i want to block all porn website that can be access by user


    Manish Chaudhary

  • Ramin Feb 9, 2010 @ 7:45

    how to deny that user cannot download with using dmaster.exe

  • Mian Rehan Ahmad Feb 24, 2010 @ 10:57

    its good thanks a lot

    very nice

  • zaheer Feb 28, 2010 @ 6:42

    i want to block images and video through squid server
    plz help me

  • arman Apr 5, 2010 @ 6:15

    any say to me
    how to block dpwnloading in internet
    any knows pleas help me

  • Manish Chaudhary Apr 9, 2010 @ 11:51

    hiiii sir
    i have done user authentication and contain filtering in squid proxy server it is working good but io want to restrict all porn website only for student user not for HCl user so how can i configure user base contain filtering
    Thanks and Regards
    Manish Chaudhary

    • John_Umesh Dec 22, 2010 @ 9:27

      U can simply add deny rule for restriction on IP base.
      Select the user to restrict add an acl with all IP addresses, add deny rule for that Acl (name that ACL as Student_Access etc)

      This may solve your problem.


  • Manikandan May 12, 2010 @ 10:03

    This forum site is more more useful for beginners…

  • hadi Jul 24, 2010 @ 1:11

    thx sir its work

  • prem kumar Jul 30, 2010 @ 13:59

    I want to block and how can i do that

  • Nur Cholikul Anwar Aug 10, 2010 @ 7:42

    Tks for your nice post very hepfull


  • Firro Sep 28, 2010 @ 15:29

    How can I stop youtube videos from playing on the clients at my network without blocking the actual Website. Em using Squid Proxy server

  • Bishal Nov 16, 2010 @ 6:15

    Hello all,

    I have different scenario. I have linux firewall and squid installed in different server.
    How can forward all lan clients to squid box from linux router, since forwarding from cisco router make squid box see all client coming from linux gateway ip. I want to see individual ip logs in squid box. How is it possible?

    cisco router
    Squid box (—–|——-Linux router (172.16.103)
    LAN CLients (

  • Henry Mar 18, 2011 @ 3:42

    Hi Friends,

    I want to download a film form the internet but was block.
    Is there any possible solution?

  • Ambicapathy Apr 15, 2011 @ 22:40

    Hi I am new to this forum..Very useful for me where I blocked the contents using the above mentioned source codes. It works perfectly.

    But I need to allow the users to download a particular exe file alone. Help me how to do that in the squid.

    Help from anyone is highly appreciated.

  • Vicky Jun 15, 2011 @ 7:44

    hi vivek,
    is it possible to customize squid to view download rates by the different IPs & manually terminating the downloads ?
    objective is to prevent big downloads (like movies,softwares) and not to penalise users requiring a small download of eg 3MB.

    vicky [at]

  • Rathish Babu Jul 8, 2011 @ 12:10

    I want to give internet access control in my office. Now am using Ubuntu server and squid 2.7. I want to give access some web sites only to particular IP and want to give no internet access to some IPs. How it possible?

  • muzzmail Sep 8, 2011 @ 10:42

    i am use windows Xp 2000 kindly help me?
    how can i use download files becoz my office is block all downloading

  • Ambicapathy Oct 3, 2011 @ 14:58

    Hi experts please help me in blocking online games website using squid proxy. I tried many things. but nothing worked. I want to block and other flash games websites.

    Please help me with this.

  • ratnakarreddy Jan 9, 2012 @ 11:10

    Hi, all
    I am using cent os 5.5 and my proxy server is squid server.

    My problem is i want to allow one of my users in the company can access a website and none of the remaining should not access..

    client ip is

    only this user should access this website


  • Chetan Jan 24, 2012 @ 8:35


    I have installed squid 3.0 in our network.
    everything is fine except, i am not able to open PDF files in my browser and Not able to attach files from gmail and yahoo.
    I have checked with upload size and download size. its correct.
    I think problem is with flash player or something else.
    Please provide me solution for the same.
    Thank you

  • naveen May 5, 2012 @ 5:18

    when i trying in this process in rhel 6 squid service is not start.
    squid service is failed.
    plz help me

  • vinod Jun 7, 2012 @ 8:59

    sir i am using rhel 6
    how to block downloading mp3 mp4 flv
    sir pls help me

  • Trillion Jul 18, 2012 @ 13:36


    Please check the content of squid.out. This will tell you what is wrong with your squid.

  • Rirhandzu Jul 19, 2012 @ 10:33

    please help i have an internet cafe’, and i use windows 7, how can i use/install squid
    on it, to block those files.

  • rodel banez Aug 23, 2012 @ 3:30

    Can somebody give me the code on how to disable images from displaying on the browser. I was able to do this a long time ago in my squid. but i can not remember anymore.. I hope to hear a responce from anyone.. thank you…

  • Rahul Sep 12, 2012 @ 5:16

    I want to block a verious proxy sites in my network so somebody help how to block proxy sites?

  • Priyadarshy Bhaisare Dec 25, 2013 @ 13:59

    For security and to save bandwidth I would like to configure Squid proxy server such way that I do not want my users to download all of the following files:

  • IQ Jan 11, 2014 @ 15:48

    In squid how I can block domain of a website like fb?

  • IQ Jan 11, 2014 @ 15:50

    In squid how can i do content filring?

  • Prashant Mar 11, 2014 @ 14:51

    Is there a way in which DAP and Torrents can be blocked using a proxy server (squid)


    • simplewallsoftware Apr 2, 2014 @ 10:59

      Torrent cant be blocked by squid.
      I see Intrusion Prevention System like SNORT/SURICATA have capability to detect and block torrent traffic based on signitures.
      Still torrent can make its own way.

      The best practice is you can block LAN User/IP address completly for 15-20 minutes who found having torrent traffic.

  • Prashant Mar 11, 2014 @ 14:55

    I am unable to access outlook through the proxy. Can you help.

  • jitendra karadia Sep 29, 2014 @ 4:52

    have installed squid 3.0 in our network.
    everything is fine except, i am not able to open PDF files in my browser and Not able to attach files from gmail and yahoo.
    I have checked with upload size and download size. its correct.
    I think problem is with flash player or something else.
    Please provide me solution for the same.

  • Buvi Sep 23, 2015 @ 5:38

    can anyone tell me how to restrict the download and upload limit to 5 mb in squid.
    file more than 5 mb should not be downloaded

  • nadav Apr 6, 2016 @ 20:11

    Is there any guide about blocking files by their signatures using squid ?
    I want to write my own code to check if a file have the specific signature and block it if necessary and use this code with squid.
    Will really appreciate any help.

  • Umesh Zala Oct 28, 2016 @ 4:35

    this can help to block file types.

    acl blockExtensions rep_mime_type -i “/etc/squid/extension.acl”
    http_reply_access deny blockExtensions

    file contain of “/etc/squid/extension.acl”


    this will block :
    application/octet-stream (.exe, .bz2, .core, .cab, etc..)
    audio/mpeg (.mp2, .mp3, .mpga )
    video/x-msvideo (.avi)

    you can add more file types to block by ref. from mime.conf file.

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