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Installing squid as a sibling to an already existing Parent squid.

squid as a sibling to an already existing Parent.

  1. We are trying to create a sibling squid which connects to a Parent squid.
  2. Parent Squid only allows with username/password.
    Assumption : We already have a parent squid which uses authentication.
    The reason why we do this is to make a single squid authenticate on behalf of all the nodes in the network.
    In the current scenario, all the node which are in 172.22.x.x series which need to access the internet proxy, would have to add username/password to their proxy setting, which is not secure and very difficult to maintain.
    So what we do is to create a sibling squid which does the authentication for us.
    [172.22.x.x] —-→ [sibling squid] ⇐==(authenticate)==⇒ [parent squid] → (( internet ))
Command below install squid. 
 [root@server-cloudera-manager yum.repos.d]# yum install squid
 Loaded plugins: product-id, rhnplugin, security, subscription-manager
 There was an error communicating with RHN.
 RHN Satellite or RHN Classic support will be disabled.
 Error communicating with server. The message was:
 Temporary failure in name resolution
 Setting up Install Process
 Resolving Dependencies
 --> Running transaction check
 ---> Package squid.x86_64 7:3.1.23-9.el6 will be installed
 --> Processing Dependency: libltdl.so.7()(64bit) for package: 7:squid-3.1.2
 --> Running transaction check
 ---> Package libtool-ltdl.x86_64 0:2.2.6-15.5.el6 will be installed
 --> Finished Dependency Resolution

 Dependencies Resolved

 ===========================================================================
  Package               Arch            Version                  Repository
 ===========================================================================
 Installing:
  squid                 x86_64          7:3.1.23-9.el6           rhel-6-serv
 Installing for dependencies:
  libtool-ltdl          x86_64          2.2.6-15.5.el6           rhel-6-serv

 Transaction Summary
 ===========================================================================
 Install       2 Package(s)

 Total download size: 1.9 M
 Installed size: 6.4 M
 Is this ok [y/N]: y
 Downloading Packages:
 (1/2): libtool-ltdl-2.2.6-15.5.el6.x86_64.rpm
 (2/2): squid-3.1.23-9.el6.x86_64.rpm
 ---------------------------------------------------------------------------
 Total                                                             233 kB/s
 Running rpm_check_debug
 Running Transaction Test
 Transaction Test Succeeded
 Running Transaction
   Installing : libtool-ltdl-2.2.6-15.5.el6.x86_64
   Installing : 7:squid-3.1.23-9.el6.x86_64
 rhel-6-server-rpms/productid
 rhel-server-dts-6-rpms/productid
   Verifying  : 7:squid-3.1.23-9.el6.x86_64
   Verifying  : libtool-ltdl-2.2.6-15.5.el6.x86_64

 Installed:
   squid.x86_64 7:3.1.23-9.el6

 Dependency Installed:
   libtool-ltdl.x86_64 0:2.2.6-15.5.el6

 Complete!
Installation in complete. Now setting chkconfig for squid.
 [root@server-cloudera-manager yum.repos.d]# chkconfig squid on

Configuration of Squid.

We are configuring UK squid as a subling to the parent squid running in Atlanta. This is how its going to work.
  • Step 1. Configure squid with cache_peer on cloudera-manager.
  • Step 2. Configure all the datanodes to connect to our proxy.
    Working. And more on this here : http://wiki.squid-cache.org/Features/CacheHierarchy
    More on cache_peer : http://www.squid-cache.org/Doc/config/cache_peer/
  1. 172.22.x.x will connect to sibling squid on port 18716
  2. Sibling squid will by-pass the requests to parent squid on port 18717 using login authentication.

squid Configuration.

Configuration currently on squid. Assuming we are allowing 172.22.0.0/16 network.
Important lines to look for.
Allowing network.
 # Allowing `172.22.0.0/16` network. 
 acl localnet src 172.22.0.0/16  # RFC1918 possible internal network
Setting port - sibling squid will be listening on this port.
 # Squid normally listens to port 3128
 http_port 18716
Important cache_peer to connect to parent. Here parent_ip_addr will be the parent IP.
 # setting `cache_peer`
 cache_peer parent_ip_addr parent 18717 0 proxy-only login=username:password default
Making sure all the request go through the parent
 # we are making sure that all the traffic goes through the parent.
 never_direct allow all
Here is the complete configuration.
 #
 # Recommended minimum configuration:
 #
 acl manager proto cache_object
 acl localhost src 127.0.0.1/32 ::1
 acl to_localhost dst 127.0.0.0/8 0.0.0.0/32 ::1

 # Example rule allowing access from your local networks.
 # Adapt to list your (internal) IP networks from where browsing
 # should be allowed

 # Allowing `172.22.0.0/16` network. 
 acl localnet src 172.22.0.0/16  # 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

 #
 # Recommended minimum Access Permission configuration:
 #
 # Only allow cachemgr access from localhost
 http_access allow manager localhost
 http_access deny manager

 # 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

 # 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

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

 # Squid normally listens to port 3128
 http_port 18716

 # Uncomment and adjust the following to add a disk cache directory.
 #cache_dir ufs /var/spool/squid 100 16 256

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

 # setting `cache_peer`
 cache_peer parent_ip_addr parent 18717 0 proxy-only login=username:password default

 # we are making sure that all the traffic goes through the parent.
 never_direct allow all

 # 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

Restart squid

 [root@server ~]# service squid restart

Configuration of clients to connect.

Add the below lines to the env of the node which needs internet connection.
 export http_proxy=http://sibling_squid_ip_addr:18716
 export https_proxy=$http_proxy
 export ftp_proxy=$http_proxy

Configuration on yum.conf on all HOSTS.

Add the below line in the end of yum.conf file.
 proxy=http://sibling_squid_ip_addr:18716
​
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