KVM Revisited Part I - Multiple VLANs

Posted on Tue 15 September 2015 in misc • Tagged with kvm, vlan

I've decided to rebuild my KVM lab on OpenSUSE 13.2 and to try and finish documenting the process of a fully functional KVM lab on multiple VLANs.

Install KVM with yast2

I used the "Install Hypervisor and Tools" in yast2 to install KVM.  I also allowed it to create …

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Setting Up VLANs and DHCP server in ScreenOS

Posted on Mon 14 September 2015 in misc • Tagged with screenos, vlan

In this example I wanted to create a VLAN attached to e0/1 for use with my KVM lab.  You'll notice I give this interface an IP address, this is so that I can have my ScreenOS device do all the routing / NATing / firewalling in isolated VLANs. I also create …

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Posted on Sat 08 August 2015 in misc

Every year or so I rebuild my machine and forget how to enable the ssh-askpass tool with ssh-agent from XDM display manager

cp /etc/X11/xdm/sys.xsession ~/.xession

cp ~/.xinitrc.template ~/.xinitrc

# Add ssh agent config for loading keys

if test -S "$SSH_AUTH_SOCK" -a -x "$SSH_ASKPASS"; then 
       ssh-add ~/.ssh …

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Passing CFLAGS and LDFLAGS to cgo

Posted on Sun 12 July 2015 in misc • Tagged with go, openbsd

I was trying to build https://github.com/systemfreund/go-libshout which wraps the C libshout library with Go.  On Linux this worked fine, but on OpenBSD this was a bit more of a challenge as cgo could not find libshout.  (install libshout with pkg_add first)

Although -lshout is specified as …

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Ansible ad-hoc commands

Posted on Mon 01 June 2015 in misc

Create an inventory file


Run a command on all hosts ansible -i inventory_file all -m command -a "uptime"

This specifies the inventory file (-i) run on all hosts (all) and run the command module (runs a remote command) with the module …

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Real Time Scheduling for audio in openSUSE

Posted on Sun 08 March 2015 in misc

I was getting the following message from jack / hydogen

Cannot use real-time scheduling

To solve this I added the following to  /etc/security/limits.conf

@audio - rtprio 99
@audio - memlock 250000
@audio - nice -10

and also added myself to the audio group (sudo usermod -a -G audio jon)

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Bulk Filename Rewriting

Posted on Sat 08 November 2014 in misc

In zsh you'll find zmv (autoload zmv) and in zmv it's easy to rewrite bulk files.  For example, I had some downloaded files that were something.mp3?id=8795294528 etc and wanted to cut off the cruft at the end.

zmv '(*.mp3)*' '$1'

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Strip comments from an XML file

Posted on Sat 18 October 2014 in misc

Ever had an xml file bloated with comments? Here's a great one-liner for striping them.

tidy -quiet -asxml -xml -indent -wrap 1024 --hide-comments 1 file.xml

Thanks to http://stackoverflow.com/questions/1464697/stripout-comments-from-xml

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Convert pem certificate to pkcs12 / p12

Posted on Thu 21 August 2014 in misc • Tagged with openssl, certificates

openssl pkcs12 -export -in widgets.crt -inkey widgets.key -out widgets.p12

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Multiple desktops with xrandr on fluxbox

Posted on Fri 11 July 2014 in misc • Tagged with xrandr

I use fluxbox.  Sometimes I work with multiple screens, sometimes I don't, sometimes those screen are various resolutions.

To see what screens I have available I run

xrandr -q

from there I can see what screens and what resolutions I have availble.  Then I can configure my setup with appropriately …

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