Unifi Controller 5 on Ubuntu 16.04 LTS

UniFi Controller is server application to manage UniFi Access Points by Ubiquiti Networks.

  • Download Controller 5 from Ubiquiti site
  • Install

    sudo gdebi unifi_sysvinit_all.deb
    

  • Start unifi service
    service unifi status
    
  • visit
    http://localhost:8443
    

Under the hood

  • compatible with Java 6, 7 & 8
  • MogoDB included
  • uses 8443, 8080, 8880, 8843, 27117, 3478, 8881, 8882

Some service that might uses the above ports

  • LXD – 8443
  • Apache2/httpd or Nginx – 8080

Make sure they are not running or not using the port before starting the unifi service.

Other resources

Printer dialog freezes after setting Properties

Problem

Printer dialog freezes after setting Properties of (any) printer.

Setup

Hardware

  • DELL Optiplex 9020
  • HP LaserJet 400 M401d (connected with USB)

Software/driver/firmware

  • Windows 7 64-bit
  • UAC notify
  • HP PCL 6 driver for Windows 7 64-bit
  • HP printer firmware 20160224

Steps tried before solution

  • carry out sfc /scannnow
  • carry out chkdsk
  • tried updating to lastest firmware and drivers
  • tried different setting in printer properties such as spooling, bidirectional support, rendering, etc.
  • change user role
    • When the user role is User, the printer dialog box freezes.
    • If the user role is Admininstrator, the printer dialog box does not freeze.
    • If the user role is Power Users, the printer dialog box does not freeze.

Solution

Set the user role to Power Users.

Remark

  • This will not solve all the freeze cases as there were other causes
  • Setting the user role to Power Users may not be feasible in certain cases.

Terminal alternative for Mac OS X

Terminal is part of the developer/administrator’s day to day tasks. Mac built-in terminal lacks features and the followings are the alternative I am using

  • iTerm2 – a terminal emulator of OS X that does amazing things
  • HyperTerm – JS/HTML/CSS Terminal

Bonus

If you want to learn terminal commands, head to Command Line Fu

Books

Other list

Deluge: ‘PreferencesManager’ object has no attribute ‘do_config_set_func’

Deluge is a torrent client. Some days ago I updated it to latest version (1.3.12) on my ArchLinux and the Scheduler plugin was not working as it should.

I found the following error in the log

AttributeError: 'PreferencesManager' object has no attribute 'do_config_set_func'

In the forum title Scheduler locked in slow mode, the reply stated

Yes sorry I make a mistake in 1.3.12 when fixing another issue. Here is the fix applied for next release: http://git.deluge-torrent.org/deluge/commit/?h=1.3-stable&id=cdf301601fe71bd697f3796cf0a5656d437d140e
Continue reading “Deluge: ‘PreferencesManager’ object has no attribute ‘do_config_set_func’”

Elite FTTx internet connection quality of service

When we are sending or receiving something over the internet (e.g. Photo, web page, document), that something is divided into many smaller packets and sent/received via network connection.

Therefore, good connection means sending and receiving those packets without loss on the way (no packet loss). The world is not ideal and so the internet protocol was prepared to compensate for it. However there is limitation to the packet loss.

Wikipedia stated that

Losses between 5% and 10% of the total packet stream will affect the quality significantly.”[6] Another described less than 1% packet loss as “good” for streaming audio or video, and 1-2.5% as “acceptable”.[7] On the other hand, when transmitting a text document or web page, a single dropped packet could result in losing part of the file,

Jeremy Collake’s post stated that

In my opinion, sustained packet loss of 1% or more should be considered a major network performance issue that needs fixed. If it’s 5% or more, you have serious issues.

So, let’s look into my internet connection, Elite Fibre to the home FTTH or FTTx 1Mbps connection.

FTTx package loss

The connection already lost 15.7% of the packets on the way to (assumingly) Elite.

The lost percentage is triple of the serious problem level. It seemed I have more than serious issues and the most serious issues is Complaint department’s only method for problem solving is restart the Huawei device and asked me to wait for 5 to 10 minutes every single time.

Remark: This is the follow up to the following tweet