Adblocking with DNS

Ads on websites can be both annoying and resource intensive for older PowerPC systems. Waiting for the browser to load all the ads just so you can use the site can be trying on your patience. This is where adblocking becomes a great help.

Dan has a really good post comparing different types of adblocking tools for TenFourFox. I would like to suggest another method you can use that will take the work of adblocking off of your browser and machine by using DNS. If you have a spare machine (I will be using my Mac mini G4 running Jessie) then setting this up will be pretty simple.

First we will install bind9 then setup DNS caching and forwarding. Then we will setup the adblock portion. Finally we will set up a simple webserver to present a transparent pixel instead of the ads.

Setting up DNS caching

First we will need to install bind9 if you have not already. This is as simple as running the command as root, apt-get install bind9. Next you will want to edit the file /etc/bind/named.conf.options. Below is my file.

acl goodclients {;

options {
    directory "/var/cache/bind";

        recursion yes;
        allow-query { goodclients; };

    // If there is a firewall between you and nameservers you want
    // to talk to, you may need to fix the firewall to allow multiple
    // ports to talk.  See

    // If your ISP provided one or more IP addresses for stable
    // nameservers, you probably want to use them as forwarders. 
    // Uncomment the following block, and insert the addresses replacing
    // the all-0's placeholder.

     forwarders {;;

    // If BIND logs error messages about the root key being expired,
    // you will need to update your keys.  See
    dnssec-validation auto;

    auth-nxdomain no;    # conform to RFC1035
    listen-on-v6 { any; };

The acl section defines who is allowed to ask queries to the DNS server. This stops unwanted people from trying to use your server. It is better suited if this was server was accessible from the internet, but it is good practice to do.

Next we want to turn on recursion and define who is allowed to query. DNS recursion is when the DNS server queries other servers on behalf of the client and sends the reply back.

Then we will define the forwarders to use. Some people refer google DNS, but I like using OpenDNS. This should be all you need to set up caching. A great tutorial on DNS caching the can be found at Digitial Ocean.


Now you need to get a blacklist file, which can be found here. Select the bind8 option and download the file. The open it and edit the zone lines to look as follows.

zone “” IN { type master; notify no; file “/etc/bind/”; };

If you are handy with vim then doing this should be really quick and easy.

The next thing is to copy the file to the /etc/bind directory and add this line to the /etc/bind/named.conf.local file.

include “/etc/bind/blacklist”;

Now it is time to create the /etc/bind/ This will redirect the ad urls to the simple webserver we will setup shortly. You want to set the A records to point the web server. In my case the mini serves as both. Here is my file.

$TTL 86400 ; one day

@ IN SOA (
2002061000 ; serial number YYMMDDNN
28800 ; refresh 8 hours
7200 ; retry 2 hours
864000 ; expire 10 days
86400 ) ; min ttl 1 day

A web server

@ IN A web server
* IN A web server

Now you want to restart bind so that it takes all these changes you made. The first command to run is named-confcheck. This does a sanity check on the configs. If all is good then you should return to the prompt. Then to restart the command is systemctl bind9 restart and to check status of the service systemctl status bind9.

This finishes all that you need to set up the DNS server.


Like I said in the beginning we want to set up a simple server to present a transparent image to replace the ads. If not then you page will full of page not found errors.

Pixelserver is a simple pearl script that can be found here. Download the file and edit it so that the listening ip address is your server. Then you change the permissions and run the server.
chmod u+x

Now point your machine to get DNS requests to your  server and test. Here is an example of a successful query.
herminio-hernandezs-power-mac-g4:~ herminio$ nslookup
Server: dns server
Address: dns server#53

Address: pixelserver

You should see the domain name point to your web server. Now browse the web ad free!


If you want to start the script on boot. Then you going to have it managed by systemd. This is not too hard to do.

First I put a copy of the script in the /usr/bin directory. Then entered the /etc/systemd/system directory and create a service file ( I called mine pixelserv.service). Here is what it looks like.




Then run systemctl enable pixelserv.service after run systemctl restart pixelserv.service. Now check to see if systemd is running the service.
root@debian-minippc:/etc/systemd/system# systemctl status pixelserv.service
● pixelserv.service -
Loaded: loaded (/etc/systemd/system/pixelserv.service; enabled)
Active: active (running) since Thu 2015-11-19 00:37:26 CST; 7s ago
Main PID: 5345 (
CGroup: /system.slice/pixelserv.service
└─5345 /usr/bin/perl -Tw /usr/bin/


If you do not turn off dnssec-validation in the /etc/bind/named.conf.options file then forwarding will break. Change the setting to what you see below then restart bind.

dnssec-validation no;


If anyone is stuck with provider wifi router that will not let you modify the DNS option in DHCP then you can add this line to the /etc/dhcp/dhclient.conf file.
prepend domain-name-servers server ip address
Then run the command dhclent <interface> to restart dhcp and you should be good.

PowerPC parts exchange?

I have had this idea for a while, but it somehow always went to the back of my mind.  What would you guys think of me adding a parts exchange area to this blog?  I'm asking my fellow authors as well as all the readers.

It would simply be an area on this blog where fellow PowerPC users can give and receive any spare parts they have, especially if they don't really have a use for it themselves.  If we do this, I would like to start it as a pure parts exchange, where the only real money involved is for shipping.  If it goes well then we could even add the ability for people to use it as a sort of PowerPC-specific Craigslist of sorts, but parts are MUCH cheaper to ship compared to systems.

I'm not talking about you all sending spare parts to one place, then making them available to others, as that would be horribly inefficient, but rather a page here to put people that have and/or need parts in touch with each other.  You would then work out your details with each other in private, in your preferred method of communication.  A central parts portal, if you will, for our always shrinking little PowerPC community.

So tell me what you guys think.  I don't want to add this here if no one will really use it.

Since none of the Apple PowerPC parts can be bought new any longer, I think an exchange could really fill a parts void for many.

Looking for a sponsor

This blog has grown in author size by 500% since I started it, and with those extra authors comes all their hardware.  Our hardware sometimes needs new parts or upgrades, and we could use more help supplementing these costs.

All funds gained would be available to all the authors as needed, and will increase the quantity and detail of our posts because of simply having more to write about.  A sponsor would also give us more motivation, because we are backed by someone who wants to be associated with us.

I am of the thinking that a single sponsor would be best, and really have no idea what to charge; so this would be something we need to negotiate.  The potential sponsor would preferably be someone with like-minded thinking to us; ie. empowering the users of technology, rather than just the industry.

If you have any questions, please ask in comments, or if you prefer to be more on the down low, you can email me.

We do accept donations also, if you prefer that method of support.

New SATA PCI card findings

This will be brief...  as there really isn't much to tell, but a more recent finding has changed everything for me.

About three or four years ago, I had come to the conclusion that booting from SATA PCI cards was only about 99.9% stable.  This is because every so often things would just lock up system-wide, and I would be forced to do a hard boot.  Not a good thing when you're smack dab in the middle of important work.  After tolerating it for a couple years...  I finally decided that I would stick to SATA card attached drives for storage only, and boot from IDE/PATA drives instead.

About four or five months ago, I realized that during all those system lockups I had drive sleep enabled.  So I decided to try it for a while without any type of sleep enabled, other than display sleep, which has no effect whatsoever on hard drives.  I never use system sleep, as my systems are always 24/7 on, but I normally use drive and display sleep on every OS.

So I have now been running a WD Caviar Black 2TB as my boot drive for about five months, with drive sleep disabled on every OS, and have never once had an issue.  I have now found 100% reliability with SATA card booting!

The WD Black is the perfect drive to use in a system where drives don't sleep, because it's built for higher endurance than most drives, and has more performance to go along with that.

I had already tried every version of firmware for my FirmTek SATA cards, and nothing solved it, but disabling drive sleep did.  The only real difference now in my computing habbits is that I need to unmount all the externals I'm not using, since they are typically backup drives, and don't go to sleep any longer. 

Keep in mind that these finding are all based off use in two Sawtooth, along with one Gigabit Ethernet system.

Anyway, I had told some readers in the past via comments that SATA card booting wasn't 100% stable, and I just wanted to share how I did find that sweet spot on my hardware.

For the record...  this is all with the FirmTek SeriTek/1S2 PCI controller; I own three.  The Sonnet 2-port PCI is the same card, as they are made for Sonnet by FirmTek.  By the way...  the best firware to use in G4 towers is 5.1.3.  You still need to disable drive sleep, but the newer firmware (5.3.x) is meant for early G5's with standard PCI, and most of these cards ship with the newer version.  So if you have a G4, and you have the 5.3.x firmware, you need to downgrade to 5.1.3 for best results.  You can download the 5.1.3 firmware here.

Please share any SATA PCI controller stories and findings you may have in comments.

G5: (And G4) Nouveau Modesetting Bug and Fix Explained

This is an expansion of the bug report Dan linked to in the previous post here at the PowerPC Liberation blog regarding a specific PPC bug which happened to break nouveau modesetting for PPC Nvidia card users. Much of what I am about to discuss is a already covered in relevant bug report, but I thought I would put it out here with the hope that more individuals would learn about the bug, what it consisted of, the workaround, and how it was fixed.  So with these goals in mind, let us move to the meat of this post.

The Bug

The same Debian user, Peter Saisanas, who reported on the page size and MSI interrupt issue with nouveau on G5 PowerMacs and supplied a working kernel for it, was also the individual who reported on the broken modesetting bug I am discussing in this post. Kernel versions starting after 3.18.16 started to showcase problems attempting to extract the FCODE ROM / DCB block for PPC machines' GPUs through the machine's Open Firmware (OF) device tree.

What are these FCODE ROMs and DCBs?  FCODE ROMs are essentially Open Firmware expansion image ROMs containing bytecode as well as PPC native code that include the necessary graphics device drivers and information for both boot-up and run time. It is one of the ways Apple closely tied the hardware with its software back in the day.

On the other hand, DCB stands for Data Control Block, which is at its very core just a type of data structure that describes the dataset in a program. In the context of our situation, it is just essentially the information about the graphics card's VBIOS and how and where to load it.

This is only part of the story though.  The question was why was it not extracting these two things properly? Turns out that the VBIOS within OF on PowerMacs does not contain a PCIR section (this holds information about the PCI expansion ROM), which the nouveau driver's VBIOS parser now requires by default.  The actual GPU PROM contains a PCIR section, but that is still separate from the OF VBIOS.

So with a PPC system unable to load this data, the kernel has a hard time communicating properly with your graphics card.  Which in turns means the Nvidia card's power and capabilities are not being fully utilized. And as a result of that, the end user ends up still using the nouveau driver, but with completely software rendered graphics.  This can be and usually is quite the disappointment in terms of performance on our old PPC machines.

The Workaround

The work around is quite simple and straightforward fortunately and will likely be the means for several users to at least have the 2D driver working until the patch hits mainline nouveau and works it way down into a later release of nouveau in Debian.  That is unless you want to try and install the patch of which I will discuss later.

Essentially, all that is needed is for you to download the x86 VGA BIOS ROM for your specific Nvidia card and configure (force) your system to load that firmware for your graphics card at boot up.  I will break it down in a few more steps though for the sake of simplicity.

1. Shutdown your system and pull out the graphics card to see exactly what manufacturer and BIOS your card consists of so you know what version you should download.

2.  Browse out to Tech Power Up's VGA BIOS database.  Search for and download the appropriate firmware for your card using the info you obtained earlier from the markings on the card.

3.  Once downloaded, rename it to something simple and related to your Nvidia card version.  For example, I used GeForce_7800_GS.fw for my Nvidia card. 
mv BFG.7800GS.256.051221.rom GeForce_7800_GS.fw

4.  Copy this file to your /lib/firmware/ directory.  You will need root permissions to do this.
sudo mv GeForce_7800_GS.fw /lib/firmware/

5. Add a line similar to below to your desired kernel(s) in your /etc/yaboot.conf file.
append="options nouveau config="NvBIOS=GeForce_7800_GS.fw"

6.  Apply the changes per usual.
sudo ybin -v

6. Reboot and once again enjoy 2D acceleration.

The Fix

Peter Saisanas reported a few days ago that a patch was created via a cloned code repository of the existing nouveau driver that should hopefully eventually hit mainline soon.  I thought it would be sort of interesting to view what changes were made in the commit to resolve the issue.

A direct link to the specific patch can be found here.  From the developer Ilia Mirkin's notes, the patch essentially forces the system to always accept the OF VBIOS.  The only changes made according to the commit were within the priv.h, shadow.c, and shadowof.c files. I thought it would be interesting to look and dissect some of those changes (mostly the ones I can figure out with a quick glance). Follow along with the highlighted changes you see within the link to the patch/commit above and you should be able to see some of what I am talking about.  I was going to post the code, but could not make it format and display in a clean and easily readable fashion as it would just squish everything into one line.

For the header file, two easily noticeable changes are two bool (true or false) variables that were added for the nouveau driver to be aware of whether or not the VBIOS it is parsing contains a PCIR section and another indicating whether the VBIOS checksum should be ignored or not.  A third size variable is declared as well that as we will see later holds the size of the OF VBIOS and image it has read. Pretty straightforward.

As for the edits in the other two files they are a bit more complex, but not much.  In shadow.c, an additional if statement is added to handle the situation where a PCIR section is NOT present. Also, an if statement below that was moved so that it was nested in the else statement in the above if else logic that is there for handling different situations that would result in debugging and error reporting.  After that you can see some additional logic added to an if statement to tell the nouvea driver to ignore invalid checksums.

Last, but not least, there is shadowof.c, which is probably the most difficult in terms of understanding the changes. First, a new header file (core/pci.h) was included. Based on name alone, I have a feeling this header defines the interface through which linux can communicate with the PCI bus and devices on a system. I am not entirely positive about the length calculation addition, but I do know a new of_size function has been created that simply returns the size of the data that has been extracted from OF and set inside of a size variable later on in the code.  Here, the two bools referenced earlier are set to true, which again basically forces the nouveau driver to always accept the image extracted from OF.  The rest is not as straightforward.  It would probably help tremendously to peruse some of the other code within the driver.

According to Peter, he was able to install the patch, but not without some additional edits to shadowof.c.  I have yet to attempt it myself, but will do so here in the next few days and post the required changes needed to install this latest patch.

Hopefully, you, the readers, have read this post and are taking away some new knowledge of nouveau, loading of roms, and reading code, as well as learned some new terms related to your PPC computers.  Once again, it is encouraging that these bugs are receiving attention and being fixed. I still strongly believe we can eventually reach a point where we can have 3D acceleration fully working on our Nvidia cards with the nouveau driver. It just involves us using our voice on the web, filing bug reports, testing the latest and greatest, and learning other ways we can help with and in development.

If you have any questions or additional comments about what I have covered here, I encourage you to drop a comment or email me directly.  Or if I am just flat out wrong about something, tell me as well as I would hate to be spreading false information.

HTTPS is now availible here

Recently, Google added an HTTPS option to all Blogger blogs, and I am of course choosing to enable it here.  So to use this blog with a secure and encrypted connection, you can bookmark this link, or simply add an 's' manually after http in your browsers address bar.

The advantages Google gives for using this new encrypted option:

  • It helps check that your visitors open the correct website and aren’t being redirected to a malicious site.
  • It helps detect if an attacker tries to change any data sent from Blogger to the visitor.
  • It adds security measures that make it harder for other people to listen to your visitors’ conversations, track their activities, or steal their information.

So please...  use this if you feel the need, and enjoy more security and privacy here.  If you link to us, please feel free to add https to the address you link to.

Let me know if you have any issues with it, or any thoughts you want to share on the matter.