Mount USB disk to server

I want to add some USB disks to my server (CentOS7) but need them to always be the same device.

Use udev to identify the disks:



udevadm info --attribute-walk --path /sys/class/block/sdd | grep model
    ATTRS{model}=="Backup+  Desk   "

Add lines to /etc/udev/rules.d/custom

SUBSYSTEMS=="scsi", ATTRS{model}=="Backup+ Desk ", SYMLINK+="Seagate%n"


udevadm control --reload-rules
udevadm trigger

This should add some symlinks in /dev

Playing with ceph

Setting up Ceph

To play about with ceph I created some Centos7 nodes on OpenStack, then followed the quickstart.

http://docs.ceph.com/docs/master/start/quick-ceph-deploy/

Had a couple of issues.

Install failed with dependency issues

[admin-node][WARNIN] Error: Package: 1:python-rbd-0.80.7-0.4.el7.x86_64 (epel)
[admin-node][WARNIN]            Requires: librbd1 = 1:0.80.7
[admin-node][WARNIN]            Available: 1:librbd1-0.86-0.el7.centos.x86_64 (Ceph)
[admin-node][WARNIN]                librbd1 = 1:0.86-0.el7.centos
[admin-node][WARNIN]            Installing: 1:librbd1-0.87-0.el7.centos.x86_64 (Ceph)
[admin-node][WARNIN]                librbd1 = 1:0.87-0.el7.centos



Due to some different packaging in the ceph and epel repos - fix found in http://tracker.ceph.com/issues/10476 :


On all nodes:
echo "check_obsoletes=1" >> /etc/yum/pluginconf.d/priorities.conf

Failed adding extra monitors

[node2][ERROR ] admin_socket: exception getting command descriptions: [Errno 2] No such file or directory

I should have set up  'public network', even though the instructions seem to say I don't need it unless I have two networks.

Redoing the install with 'public network' in the ceph.conf fixed this.

No data pool by default

Only had a rbd pool initially. Not sure if this is a problem (the docs say there should be a data and metadata pool by default).

World of Warcraft on Fedora 21

Instructions copied from
https://blog.mavjs.org/world-of-warcraft-on-f20-via-wine.html

Install wine:

# sudo yum install wine

Download World of Warcraft Setup Installer from https://us.battle.net/account/download/?show=wow.

Run the installer with wine:

# cd ~/Downloads/
# wine World-of-Warcraft-Setup-enGB.exe

After the installation completes, it will ask you to login to your Battlenet Account. Instead, quit the application. Then tell it to use software rendered OpenGL by executing (it has a bug where the interface is just black canvas on some intel cards):

% export LIBGL_ALWAYS_SOFTWARE=1
% wine ~/.wine/drive_c/Program\ Files\ (x86)/Battle.net/Battle.net\ Launcher.exe

Battlenet actually allows you to play even though it hasn't finished downloading if it has reached a certain downloaded size. Either wait to finish or open the game. When you run it the first time it will take a while and FPS is not that great. Quit the game. Modify SET gxApi "D3D9" to SET gxApi "Opengl" in the following file:

$ ~/.wine/drive_c/Program\ Files\ (x86)/World\ of\ Warcraft/WTF/Config.wtf

3D printing repositories

Alternatives to Thingiverse

https://www.youmagine.com/
http://repables.com/
http://thingtracker.net/

Get all tables with columns 'columnA' or 'ColumnB' in the database

To get all tables with columns 'columnA' or 'ColumnB' in the database 'YourDatabase'

SELECT DISTINCT TABLE_NAME 
    FROM INFORMATION_SCHEMA.COLUMNS
    WHERE COLUMN_NAME IN ('columnA','ColumnB')
        AND TABLE_SCHEMA='YourDatabase';

Fedora 20 on Dell XPS 13

A few notes on setting up a Dell XPS 13 with Fedora 20.

Put Fedora 20 on a flash drive
Change to UEFI boot

Boot from flash (F12 to choose boot device)

Some settings for laptop SSD disks and power saving

TRIM for SSD disk: add discard to disc options (or replace defaults) in /etc/fstab

installed tuned and switch it on

yum install tuned
systemctl start tuned.service
systemctl enable tuned.service
tuned-adm list
tuned-adm profile powersave

yum list powertop
yum install powertop

Touchpad on kernel > 3.11.10

There is currently a minor problem with the touchpad on higher kernels. It seems that the touchpad initialises incorrectly because of i2c and PS2 interfaces.
Blacklisting the i2c-hid module

1. Open /etc/modprobe.d/blacklist.conf in your favorite text editor.
2. Add the line 'blacklist i2c-hid' (no quotes)
3. Save and reboot

See: https://bugzilla.redhat.com/show_bug.cgi?id=1048314

RPM Fusion

su -c 'yum localinstall --nogpgcheck http://download1.rpmfusion.org/free/fedora/rpmfusion-free-release-$(rpm -E %fedora).noarch.rpm http://download1.rpmfusion.org/nonfree/fedora/rpmfusion-nonfree-release-$(rpm -E %fedora).noarch.rpm'


yum install gstreamer-plugins-ugly gstreamer-plugins-bad gstreamer-ffmpeg xine-lib-extras-freeworld

Rebuild VM host with bigger disks

Disk partitioning

/boot - 500MB
swap - 18GB
/ - 30 GB
/usr - 30GB
/tmp - 10GB
/home - 100GB
/var - the remaining space

3 disks - 2x2TB + 1x1TB

Setup the 2TB disks as a RAID 1 pair - two md devices - md0 for /boot and /md1 for LVM Physical Volume

Put swap on the 1TB disk (no raid) and mounted the rest of the 1TB as /single

OS Install

Installed CentOS 6.5 - software selection - Virtulization Host

Install EPEL:
rpm -Uvh http://www.mirrorservice.org/sites/dl.fedoraproject.org/pub/epel/6/i386/epel-release-6-8.noarch.rpm

yum install ntp ntpdate
chkconfig ntpd on

OpenStack Install

The following instructions are from  RDO Quickstart : http://openstack.redhat.com/Quickstart

yum install -y http://rdo.fedorapeople.org/rdo-release.rpm

packstack --allinone

xymon

Add my local basetwo yum repo (or the http://terabithia.org/rpms/xymon/ repo)

yum install xymon-client

Set XYMONSERVERS in /etc/default/xymon-client

service xymon-client start

Add br0 bridge

This is for non-openstack kvm images




Remember to remove this server from known_hosts on any client running virt-manager, otherwise you get a 'is libvirtd running' error.

Create /etc/polkit-1/localauthority/50-local.d/50-libvirt-remote-access.pkla
With something like

[libvirt Management Access]
Identity=unix-user:markd
Action=org.libvirt.unix.manage
ResultAny=yes
ResultInactive=yes
ResultActive=yes