Advice on blocking ads

doc/EN/usage.org

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+| [[Blocking Ads]]                                         |
 
 * Readme
 After the system has installed a README file will be generated which contains passwords and some brief advice on using the installed systems. You can read this with the following commands:
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 Return to the <a href="index.html">home page</a>
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+
+* Blocking Ads
+Everyone except for advertisers hates adverts. Not only are they annoying, but they can also consume a lot of bandwidth, be a privacy problem in terms of allowing companies to track your browsing habits and also any badly written scripts they contain may introduce exploitable security holes.
+
+You can block ads for any devices connected to your local network by installing the *pihole* app from *Add/Remove Apps* on the administrator control panel. This may help to improve overall performance of your devices by not wasting time downloading unwanted images or scripts.
+
+** Set a static IP address
+
+Once you've done that then ensure that your system has a static local IP address (typically 192.168..) using the option on the control panel. You will also need to know the IP address of your internet router, which is usually *192.168.1.1* or *192.168.1.254*.
+
+When that's done select *About this system* from the control panel and see the IPv4 address (ignore the /24 part). You can use this as a DNS address in two ways:
+
+** On each client system within your local network
+
+#+begin_src bash
+sudo chattr -i /etc/resolv.conf
+sudo nano /etc/resolv.conf
+#+end_src
+
+Comment out any existing entries with a # character and add:
+
+#+begin_src bash
+nameserver [IPv4 address from the About screen]
+#+end_src
+
+Normally /resolv.conf/ will be overwritten every time your reboot, but you can prevent this with:
+
+#+begin_src bash
+sudo chattr +i /etc/resolv.conf
+#+end_src
+
+** On your internet router
+If you can access the settings on your local internet router then this is the simplest way to provide ad blocking for all devices which connect to it.
+
+Edit the DNS settings and add the IPv4 address which you got from the control panel About screen. Exactly how you do this will just depend upon your particular router model. You may also need to set the same address twice, because two addresses are conventional.
+
+** Configuring block lists
+You can configure the block lists which the system uses by going to the *administrator control panel*, selecting *App Settings* then choosing *pihole*. You can also add any extra domain names to the whitelist if they're being wrongly blocked or to the blacklist if they're not blocked by the current lists.