Howto: install Pi-hole 6.x on Dockstar/Debian 12.x (no replies)

Pi-hole seem to have withdrawn support for armv5 when they released Pi-hole v6, so we need to manually build the pihole-FTL binary in order to use Pi-hole on Seagate Dockstar , or other armv5 devices.

The following was done on a fresh install of the standard kirkwood build downloaded from this wiki ( Debian-6.5.7-kirkwood-tld-1-rootfs-bodhi.tar.bz2 ).

First, make sure you have at least 256MB of swap (v. important during compilation of pihole-FTL). I used 512MB.
- see instructions elsewhere on this Wiki on how to add a swapfile : https://forum.doozan.com/read.php?2,133753

Second step, download and build pihole-FTL, as per instructions at https://docs.pi-hole.net/ftldns/compile/

sudo apt install git wget ca-certificates build-essential libgmp-dev m4 cmake libidn2-dev libunistring-dev libreadline-dev xxd

# build nettle:

wget https://ftp.gnu.org/gnu/nettle/nettle-3.9.1.tar.gz
tar -xzf nettle-3.9.1.tar.gz
cd nettle-3.9.1
./configure --libdir=/usr/local/lib --enable-static --disable-shared --disable-openssl --disable-mini-gmp -disable-gcov --disable-documentation
make -j $(nproc)
sudo make install

# build libmbedtls

wget https://github.com/Mbed-TLS/mbedtls/archive/refs/tags/v3.5.0.tar.gz -O mbedtls-3.5.0.tar.gz
tar -xzf mbedtls-3.5.0.tar.gz
cd mbedtls-3.5.0
sed -i '/#define MBEDTLS_THREADING_C/s*^//**g' include/mbedtls/mbedtls_config.h
sed -i '/#define MBEDTLS_THREADING_PTHREAD/s*^//**g' include/mbedtls/mbedtls_config.h
make -j $(nproc)
sudo make install

# build FTL

git clone https://github.com/pi-hole/FTL.git  
cd FTL

If you run build.sh at this point , you are likely to find that it uses increasing amounts of swap, starts thrashing and eventually dies with a segmentation fault after an hour and a half :

[ 38%] Building C object src/database/CMakeFiles/sqlite3.dir/sqlite3.c.o
{standard input}: Assembler messages:
{standard input}: Internal error (Segmentation fault).
Please report this bug.
gmake[2]: *** [src/database/CMakeFiles/sqlite3.dir/build.make:90: src/database/CMakeFiles/sqlite3.dir/sqlite3.c.o] Error 1
gmake[1]: *** [CMakeFiles/Makefile2:685: src/database/CMakeFiles/sqlite3.dir/all] Error 2
gmake: *** [Makefile:136: all] Error 2

After several hours of trial, error and investigation on how to reduce memory usage during compilation using gcc's -Ox flags, I noticed that the gcc optimisations are controlled by $CMAKE_BUILD_TYPE , and this was set by default to "RelWithDebInfo", i.e with bloaty Debug info

So we need to edit FTL/src/CMakeLists.txt, and change the CMake build type to "Release" :

...
#set(CMAKE_BUILD_TYPE "RelWithDebInfo" CACHE STRING "" FORCE)
       #set(CMAKE_BUILD_TYPE "MinSizeRel" CACHE STRING "" FORCE)
        set(CMAKE_BUILD_TYPE "Release" CACHE STRING "" FORCE)

(I also tried using MinSizeRel, but compilation failed & exited as soon as there were any compiler Warnings at all ..

./build.sh install

It now built FTL in about an hour :)


Third Step: Run the pi-hole installation script.
But before we run it, we need to edit it so that it doesn't get confused when it finds an armv5tel version of the pihole-FTL executable already built:

Download the install script :

wget -O basic-install.sh https://install.pi-hole.net

edit basic-install.sh and make two edits :
.. first mod: add an additional check to permit armv5 :

# added the following 4 lines for dockstar robin 13jun2025
        elif [[ "${rev}" -eq 5 ]]; then
            # If ARMv5 is found (e.g., dockstar )
            printf "%b  %b Detected ARMv5 architecture\\n" "${OVER}" "${TICK}"
            l_binary="pihole-FTL-armv5snotdead"
        else
            # Otherwise, Pi-hole does not support this architecture
            printf "%b  %b This processor architecture is not supported by Pi-hole (%s)\\n" "${OVER}" "${CROSS}" "${cpu_arch}"
            l_binary=""

.. second mod: comment out 7 lines performing checksum check :

# commented this checksum check when building local FTL robin 13jun2025
    #if [[ ! "${remoteSha1}" =~ ^[a-f0-9]{40}$ ]]; then
    #    printf "  %b Remote checksum not available, trying to redownload...\\n" "${CROSS}"
    #    return 0
    #elif [[ "${remoteSha1}" != "${localSha1}" ]]; then
    #    printf "  %b Remote binary is different, downloading...\\n" "${CROSS}"
    #    return 0
    #fi

Now run the the install script: it should run through all the additional installation tasks, such as downloading blacklists, adding domains to the gravity database; creating cron jobs etc.

$ bash basic-install.sh

run 'pihole setpassword ', then connect to your pihole web-console using a web browser, http://yourhostname/admin/ and make sure all looks OK , especially that it shows Status='Active' at top-left, and tens of thousands of 'Domains On Lists' in the green box at top-right of the Dashboard.

Note: my dashboard was initially showing 'Error: -2' in the green 'Domains On Lists' box : I had to manually run 'pihole -g' to update gravity db to fix this.