Thursday, December 20, 2012

Reading temperature from /sys

Note to self, from http://shallowsky.com/blog/linux/kernel/sysfs-thermal-zone.html:


$ cat /sys/class/thermal/thermal_zone0/temp
27800

Monday, November 26, 2012

QEMU/KVM nested inside ESXi 5.0

Just a note to self, based on the success from the info found at http://virtuallyhyper.com/2012/07/installing-kvm-as-a-virtual-machine-on-esxi5-with-bridged-networking/ (Which has a much more detailed description - so, if unsure, go and read there!)

1) ESXi 5.0 has the nested virtualization support but it is disabled by default.

SSH into the ESXi host and add the following line to /etc/vmware/config:

vhv.allow = TRUE

2) The guest config also needs edits to enable the nested virtualization. Add the below lines to the .vmx file:

monitor.virtual_mmu = "hardware"
monitor.virtual_exec = "hardware"
cpuid.1.ecx="----:----:----:----:----:----:--h-:----"
cpuid.80000001.ecx.amd="----:----:----:----:----:----:----:-h--"
cpuid.8000000a.eax.amd="hhhh:hhhh:hhhh:hhhh:hhhh:hhhh:hhhh:hhhh"
cpuid.8000000a.ebx.amd="hhhh:hhhh:hhhh:hhhh:hhhh:hhhh:hhhh:hhhh"
cpuid.8000000a.edx.amd="hhhh:hhhh:hhhh:hhhh:hhhh:hhhh:hhhh:hhhh"
vcpu.hotadd = FALSE

After that the kvm-ok should be happy.



Monday, June 4, 2012

How does NUD compare with FHRP ?

Stumbled upon this link that compares the neighbor unreachability detection in IPv6 with redundancy protocols:

http://packetlife.net/blog/2011/apr/18/ipv6-neighbor-discovery-high-availability/

Which IPv6 prefix length to announce in the internet ?

This is mostly as a notepad entry for myself, but putting here in case anyone finds it useful.

The question is - "how long is the IPv6 prefix that I can announce?".

Here are some links to help understand the answer to this question:

RIPE recommendations

Practical experiments from RIPE on prefix visibility:

Nanog discussion about the prefix length from 2011:

Thursday, May 31, 2012

Ubuntu 12.04 bugs/quirks I hit...



Overall, when using the 12.04 in a canned version, things are pretty good. So I upgraded my workstation laptop, which is running a more customized install - fluxbox as a window manager, with a minimalist window theme. "fixed" is not necessarily a bugfix, but a fix from the functionality point of view, sometimes with slight tweaking that I deemed acceptable, so technically it is a union of "fixed" and "worked around".

A list of various "interesting" things I have encountered.  
I'll update this post as I encounter more "funny" things or as the previous funny things get fixed.