Month: March 2015

Test Router and Wifi Speed using iperf command

This posts shows how to test your local network bandwidth speed which is useful for testing router settings or letting you know if it is time to upgrade your wifi card on your laptop. This test requires a minimum of two computers, with one acting as a server for the other to connect to. I am using Ubuntu linux on these computers. All commands are in italics and run in a terminal window.

Server Computer

  • This computer should be connected by an ethernet cable to your wifi router
  • You need to know the ip address of your server computer
    • ifconfig
      • output follows
      • eth0      Link encap:Ethernet  HWaddr d0:50:99:5b:70:b2
        inet addr:192.168.1.3  Bcast:192.168.1.255  Mask:255.255.255.0
        inet6 addr: xxx::xxxx:99ff:fe5b:70b2/64 Scope:Link
        UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
        RX packets:64155953 errors:0 dropped:487 overruns:0 frame:0
        TX packets:97383655 errors:0 dropped:0 overruns:0 carrier:0
        collisions:0 txqueuelen:1000
        RX bytes:7182981438 (7.1 GB)  TX bytes:126082997710 (126.0 GB)
        Interrupt:16
    • This is the ip address from above: 192.168.1.3
  • iperf installation
    • sudo apt-get install iperf
  • run the iperf command in server mode
    • iperf -s -u -i 1 -f M
      • -s = server
      • -u = udp packets
      • -i 1 = report every 1 second
      • -f M = report in Megabytes

Client Computer, this is the computer you are testing

  • This computer can have a wifi or ethernet connection
  • installation is the same as the server
  • run the iperf command in testing mode
    • iperf -c 192.168.1.3 -u -i 1 -l 1300 -b 999999m -t 10 -f M
      • -c 192.168.1.3 = connect at the servers ip address
      • -u
      • -i 1
      • -l 1300
      • -b 999999m
      • -t 10 = amount of time to run test in seconds
      • -f M

With ethernet, I am getting 85 Mb/sec and on wifi 2 Mb/sec. Wifi is very slow on my netbook.

How to convert MythTV MySQL tables from MyISAM into InnoDB

I wanted to upgrade my MythTV MySQL tables from MyISAM into InnoDB format. When I installed Mythbuntu 12.04, MyISAM was the default database engine. Now the default database engine moving forward in InnoDB. Here are the steps I took to upgrade using phpMyAdmin. I am not sure if I documented all the steps here, so use at your own risk.

SET @DATABASE_NAME = 'mythconverg';
SELECT CONCAT('ALTER TABLE `', table_name, '` ENGINE=InnoDB;') AS sql_statements FROM information_schema.tables AS tb WHERE table_schema = @DATABASE_NAME AND `ENGINE` = 'MyISAM' AND `TABLE_TYPE` = 'BASE TABLE' ORDER BY table_name DESC;

  • Copy the output from this query and paste these results back in the “Run SQL query/queries on database mythconverg” SQL query input box.

I switched from 14.04 Ubuntu-Unity to Ubuntu-Gnome

I been running Ubuntu-Gnome 14.04 for about two weeks now and I really enjoy it and find it easy to use. I switched from the unity desktop because of crashes and errors I was getting. I had been getting crash alerts since running 13.04 unity when I first logged in after a reboot. I had been sending crash reports to Ubuntu/launchpad but finally got fed up enough that I put a fresh (erase partition and use fresh install from live cd). I have always liked the unity interface and the use of the meta/windows key to launch applications. This feels faster because my hands stay on the keyboard and I am not reaching for the mouse to access menus or a dock.

I also tried Debian Jessie and Wheezy with gnome desktop. Debian felt really fast and snappy. Debian was definately harder to setup because I had to enable the non-free (propriety) software for my hardware to work (AMD R-9 270 graphics card). I did not stick with Debian because it would not boot after a software update. I definately want to try Debian-testing again after I get hardware that is more compatible and all my hardware purchases in the future will focus on stability and compatibility with linux in the future. I have Debian Jessie installation on a spare hard drive that I use for recovery purpose and as an emergency working system that does not look as pretty but it gets the job done.

Eventually I installed Ubuntu Gnome 14.04 and installed /root and /home on LUKS encrypted partitions. I will probably run this until version 15.04 comes out. I have heard Ubuntu is shifting its graphics from wayland to mir display server. If they go mir, then I will probably wait a year to for them to get the bugs worked out before I try it.

HowTo update Ubuntu 14.04 / php5-apcu to a owncloud 8.02 supported version

After updating to owncloud 8.0.2 on Ubuntu 14.04, I was getting the following error in owncloud on the administration page “APCu below version 4.0.6 is installed, for stability and performance reasons we recommend to update to a newer APCu version.” I found this post on how to upgrade the php5-apcu package. Here is the link https://github.com/owncloud/core/issues/14386