Category Archives: Operating Systems

Setting up Squid proxy on Ubuntu 16.04 to browse blocked websites

Squid 3.5.12 can be installed and tested on Ubuntu 16.04 with the following commands:

sudo apt install squid
service squid start
sudo ufw allow 3128/tcp
wget -e use_proxy=yes -e http_proxy=http://localhost:3128 http://google.com

by default Squid listens on port 3128.

At first, Google Chrome started with Squid proxy from some external IP address:

"C:\Program Files (x86)\Google\Chrome\Application\chrome.exe" --proxy-server=http://developernote.com:3128

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How to prevent automatic restart after installing updates in Windows 10

Press Win+R, type “gpedit.msc” and press Enter:

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How to add a program to startup in Windows 10

Press Win+R, type ‘shell:startup‘ or ‘shell:Common Startup‘ and press Enter:

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How to edit Windows 10 boot menu

Press Win+R, type ‘msconfig‘ and press Enter:

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Installing NVIDIA Driver on Ubuntu 16.04

I am not sure if there were NVIDIA drivers when I installed Ubuntu 16.01 on a machine with Intel processor and GTX 1060 graphic card, but at least I saw this in the terminal (it is not clear what actually FAILED):

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Installing Google Play Services on a Windows 10 with MS VS2015

If Android support is enabled in MS VS2015, it installs Android SDK without Google Play Services and I did not find an option in SDK Manager that installs them. When I started “C:\Program Files (x86)\Android\android-sdk\SDK Manager.exe” with admin privileges, it automatically offered to install some 9 packages:

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Configuring Postfix with Yandex.ru relay in Ubuntu 16.04

Today I read that Postfix can be better than sendmail and found a great Russian article on how to configure Postfix to work with Yandex.ru relay (Yandex.ru is some kind of Russian Google). The only notice I would give is that in a Docker container I need also install rsyslog, otherwise /var/log/mail.log file is not created:

apt install rsyslog

After doing all the steps described in this Russian manual I was able to send email to Yandex.ru and GMail accounts, but GMail landed all the emails to its spam folder. My first idea was that it is because I did not configure ‘from address’ correctly, so I had the following in /var/log/mail.log, and also there was a message ‘Cannot assign requested address‘:

Oct 27 11:36:19 0675c97b78aa postfix/pickup[1210]: 8C7ECE5B72: uid=0 from=<root>
Oct 27 11:36:19 0675c97b78aa postfix/cleanup[10786]: 8C7ECE5B72: message-id=<20171027113619.8C7ECE5B72@0675c97b78aa.localdomain>
Oct 27 11:36:19 0675c97b78aa postfix/qmgr[1211]: 8C7ECE5B72: from=<root@0675c97b78aa.localdomain>, size=405, nrcpt=2 (queue active)
Oct 27 11:36:19 0675c97b78aa postfix/smtp[10788]: connect to gmail-smtp-in.l.google.com[2a00:1450:400c:c09::1b]:25: Cannot assign requested address
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Configuring sendmail with GMail relay on Ubuntu 16.04

Previously I published post How I configured sendmail for PHP on Ubuntu Server 12.04 describing how to configure sendmail to use custom SMTP server. But after switching to Ubuntu 16.04 VPS my first idea was that I can use sendmail in its default configuration, but this idea was wrong, because while sendmail worked well with yandex.ru (some Russian mail server), for example, it did not work with GMail, because GMail did not accept the mail reporting ‘DSN: Service unavailable.‘┬áin /var/log/mail.log, see my post on Ubuntu Forum for more information. Now my second idea is that using GMail as sendmail relay will prevent GMail from rejecting my mail. Below I provided a short instruction on how to realize this successful idea.

Install the packages

apt-get install sendmail mailutils

mailutils allows to run mail command.

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Fun with Bitcoin mining on a home Windows machine.

I have heard many times that there are a lot of Russian guys who build mining farms and earn money with cryptocurrencies. Who knows, probably cryptocurrencies are still only at the starting point of their growth, or probably it is too late to start mining, or as another alternative Russian government will forbid them, but anyway it was interesting for me, how much Bitcoins my home Windows computer with relatively old graphic card can mine.

I overclocked my GeForce GTX 750 graphics card a bit:

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Compiling the latest version of CMake from sources on Ubuntu

I was unable to add QML resources to a QT Quick application with CMake 2.8 installed on my machine, so I built the latest version of CMake with the following commands:

cd ~/examples
mkdir tools
cd tools
mkdir install
tar -xf ~/Downloads/cmake-3.9.1.tar.gz
cd cmake-3.9.1/
./configure --prefix=/home/dmitry/examples/tools/install/
make -j4
make install

Now my QT application is compiled and run successfully:

~/examples/tools/install/bin/cmake ../../OsgQmlTest/ -DCMAKE_BUILD_TYPE=Debug -DCMAKE_MODULE_PATH=/home/user/3rdpart/osg/CMakeModules/ -DCMAKE_INSTALL_PREFIX=/home/dmitry/examples/install
make -j4
make install

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