RouterOS’s load balancing is simple but tricky. Even Mikrotik shows an example of how to configure PCC for load balancing. It does not say how to implement it with dynamic IP. The method introduced here is simple. We will add lease scripts to WAN1 and WAN2. RouterOS will run the script to add the correct gateway IP and firewall rules to make the load balancing work.
Set custom DNS servers on Linux with resolv.conf
resolv.conf is the configuration file for DNS resolvers for all Linux distributions, including Debian, Mint, Ubuntu, RedHat, CentOS, etc. Usually we change the DNS resolvers list by editing resolv.conf. However, depends on your dhcp client configuration, resolv.conf may be rewrite after reboot. Without deep Linux experience, setting customs DNS servers on Linux maybe time consuming. But one thing we can do is make /etc/resolv.conf immutable to other program after you changed it. This will be the easier setup with no side effects on system.
Protect your WordPress from Automated Comment Spam and Brute Force Login Attack
Is your WordPress flooded with spam comment or being attacked by brute force login attempt? Thinking about spam blocking plugin? There are a lot of plug in can help you stop spam comment. You will notice it put thousands spam comments into spam folder after a while. Those Anti-Spam did a great job stopping spam comment show up in our post. There is some drawbacks for that kind of plugin. First,spam comments will be processed and store in your database before it gets deleted manually or automatically. Second, plugin like Akismet Anti-Spam will add a java-script to your site. If your site has limited resources, these kind of activities will drag down your site’s performance. If you use captcha plugin, you will also interrupt user’s experience.
Asus Z87-A MacOS high sierra upgrade prepare with clover
This guide is for upgrading your system from previous version to high sierra 10.13.x. For how to prepare USB installation kit, check here: Install Mac OS X with clover EFI bootloader on ASUS Z87a 
Fix error - Mediakit reports not enough space on device for requested operation
If you tried use MacOS’s disk utility to erase or format a old/new hard drive, you may encounter some issue. MacOS will show below error when you tried to erase or format the drive, regardless your hard drive space:
Open PDF/A PDF file without read-only mode
The file you have opened complies with the pdf/a standard and has been opened read-only. If you open a PDF/A standard PDF, in default you will not able to modify it because Adobe PDF reader or Acrobat will open it in view only mode.
Ricoh SP C250DN C252DN PPD CUPS driver for LINUX and macOS
C250DN or C252DN can be driven by setting PCL6 and use CUPS+Gutenprint driver. However, if we use Generic driver, it will not print out color.
Edit Hosts file to override DNS record for domains
Hosts file will instruct your machine to go directly to an IP address for specified domain instead of checking with DNS server. For example, point www.qualityology.com and qualityology.com to Google Cloud Platform server:
Build an extremely fast WordPress with GCP Part 2: Nginx
Apache or Nginx, what softwares should be used to for your server to achieve the maximum performance? If you have a small free server from GCP from part 1, and you want it to be able to handle average 1000 clients per second, Nginx is the best option. Apache use more server resources and must be configured properly to get the best performance. Nginx can handle very large amount of traffic even in a limited environment. We have done the loading test with the server from Google Cloud Platform from part 1 and the result was great without deep optimization. 1000 client/sec is not the maximum that this setup can get, it is the limit of the free test we could get. When we tried the same test using Apache, the test was aborted at the beginning because server crashed. That is why we will use Nginx. We are not the server expert, so we will not discuss how to optimize Apache to pass the same test. What we will need is NGINX + MySQL + PHP-FPM + Microcaching + WordPress.
iPhone's battery draining? Here's what you can do
If you just upgraded your iPhone to a new version iOS system from the old version for example from iOS 10 to iOS 11 or iOS 9 to iOS 11, you may notice that your battery is draining twice as fast or more after the upgrade. Sometime system can be lagging too. You may heard that you can turn off some features to help the battery to stay longer. However, if a smart phone needs to turn off all the features, what is the point of having a smart phone right? Here is what you can do if you experience battery issue after upgraded.