Author Archives: dmitriano

Building and running rippled on Ubuntu.

I successfully build and run rippled 1.1.2 on Ubuntu 18.04 with the following commands:

sudo apt-get -y install git cmake pkg-config protobuf-compiler libprotobuf-dev libssl-dev wget
cd ~Downloads/
cd ..
mkdir lib
cd lib/
tar xvzf ~/Downloads/boost_1_67_0.tar.gz
./b2 -j1
export BOOST_ROOT=/home/<user>/lib/boost_1_67_0
cd ~/repos/
git clone
cd rippled
git tag
git show --summary 1.1.2
git reset --hard 1.1.2
mkdir build
cd build/
cmake ..
cmake --build .
./rippled -u
284.6s, 171 suites, 1049 cases, 379760 tests total, 0 failures


Setting up time synchronization on Ubuntu

I followed the official Ubuntu time synchronization guide and installed chrony:

sudo apt update
sudo apt install chrony
cat /etc/chrony/chrony.conf
chronyc sources
chronyc sourcestats
sudo systemctl restart chrony.service
apt remove --autoremove chrony


Setting up Ethereum node on Windows 10 and Ubuntu.

After a few attempts I was able to start Ethereum Mist 0.11.1 in ‘fast’ mode on Windows 10:

it downloaded ‘geth’, connected to {“path”:”\\\\.\\pipe\\geth.ipc”} and started to sync, but when sync finished I was unable to send transactions (they were ‘denied’ for some reason).


Checking the speed of my home internet.

I have 50 Mbit internet at home. If I test its speed with I get download speed 56 Mbit/s and upload speed 5.56 Mbit/s that is really good:

and if I download a file with torrent the speed is 6+ MB/s, but if I download a file with HTTP or SFTP the speed can be less than 500 KB/s that is 10 times slower. For example, if I download Ubuntu 18.10 on my VPS the speed is 24 MB/s:


Setting up Vue.js development tools on Windows 10.

I installed Node.js and Vue.js cli with the following commands

npm install -g @vue/cli
npm install -g @vue/cli-init

and a sample application with

vue init webpack-simple my-vue-app
cd my-vue-app
npm install
npm run dev


Some GTX 1060 3GB cards have low hashrate with Ethash coins.

Ethash algorithm behaves a bit strange on my mining rig with HiveOS and 8 GTX 1060 3GB. Four MSI ARMOR cards with Sumsung memory (OC +1500 mem) have 24+ MH/s, two other cards (OC +600 mem) have 21+ MH/s and two other slow MSI cards (also OC +600 mem) have only 18+ MH/s. I tried to switch risers, PSU, PCI slots and move the cards across rigs, but with no success.

Today I did a pure experiment. I plugged one of the slow cards to a Windows 10 machine with 1000W PSU directly via PCI slot without riser, started Claymore Miner with Musicoin (that has a lower dag size than Ethereum) and got the same result as before, without OC the card had 15+ MH/s (normally it should be 19+ MH/s):


Molten SATA power connector on a mining rig.

I have a mining rig with 8 GTX 1060 3GB connected via risers, the risers are connected via SATA power connectors to Corsair HX850. When the rig stopped working I noticed that one SATA connector on the PSU is molten:


How I built QT 5.11.1 for Android on Windows

I tried to build QT 5.11.1 for Android on Windows, and “configure.bat” completed successfully, but “mingw32-make” failed with with the following error:

No rule to make target 'vulkan/qvulkanfunctions_p.h', needed by '.obj\qvulkaninstance.obj'.

It is the bug fixed in QT 5.11.2 that is planned on August/September 2018.

When I build the master branch and copied the following files from it to \qtbase\src\gui\vulkan manually:


and started “mingw32-make” again I got another error:


Mining Ethereum on Ubuntu 18.04 with GeForce GTX 1060 3GB

I am not a Linux expert, so it took me some time to configure my mining rig on Ubuntu 18.04 with NVIDIA GeForce GTX 1060 3GB, and I wrote down all the steps I did:

First I installed NVIDIA driver, but OpenCL did not install automatically with it and I installed it manually with the following command:

sudo apt install -y ocl-icd-libopencl1

Then I installed CURL:

sudo apt install -y libcurl3

not ‘curl’ and not ‘libcurl4’ packages, otherwise the miner will fail to start reporting the following error message:

./ethdcrminer64: /usr/lib/x86_64-linux-gnu/ version `CURL_OPENSSL_3' not found (required by ./ethdcrminer64)


PHP script that saves client IP address to a file.

Below I wrote down a simple PHP script that saves client IP address to a file. If the IP address of your home machine periodically changes, you can store it on a web server once a minute by scheduling a task like this:

sudo crontab -u <user> -e
* * * * * wget -q -O /dev/null -o /dev/null ""

where ip.php is the following PHP script: